mcs/mcs/cs-parser.jay

   1 %{
   2 //
   3 // cs-parser.jay: The Parser for the C# compiler
   4 //
   5 // Authors: Miguel de Icaza (miguel@gnome.org)
   6 //          Ravi Pratap     (ravi@ximian.com)
   7 //          Marek Safar     (marek.safar@gmail.com)
   8 //
   9 // Dual Licensed under the terms of the GNU GPL and the MIT X11 license
  10 //
  11 // (C) 2001 Ximian, Inc (http://www.ximian.com)
  12 // (C) 2004-2011 Novell, Inc
  13 // Copyright 2011-2012 Xamarin Inc.
  14 //
  15
  16 using System.Text;
  17 using System.IO;
  18 using System;
  19 using System.Collections.Generic;
  20
  21 namespace Mono.CSharp
  22 {
  23         /// <summary>
  24         ///    The C# Parser
  25         /// </summary>
  26         public class CSharpParser
  27         {
  28                 [Flags]
  29                 enum ParameterModifierType
  30                 {
  31                         Ref             = 1 << 1,
  32                         Out             = 1 << 2,
  33                         This    = 1 << 3,
  34                         Params  = 1 << 4,
  35                         Arglist = 1 << 5,
  36                         DefaultValue = 1 << 6,
  37
  38                         All = Ref | Out | This | Params | Arglist | DefaultValue,
  39                         PrimaryConstructor = Ref | Out | Params | DefaultValue
  40                 }
  41
  42                 static readonly object ModifierNone = 0;
  43
  44                 NamespaceContainer current_namespace;
  45                 TypeContainer current_container;
  46                 TypeDefinition current_type;
  47                 PropertyBase current_property;
  48                 EventProperty current_event;
  49                 EventField current_event_field;
  50                 FieldBase current_field;
  51
  52                 /// <summary>
  53                 ///   Current block is used to add statements as we find
  54                 ///   them.
  55                 /// </summary>
  56                 Block      current_block;
  57
  58                 BlockVariable current_variable;
  59
  60                 Delegate   current_delegate;
  61
  62                 AnonymousMethodExpression current_anonymous_method;
  63
  64                 /// <summary>
  65                 ///   This is used by the unary_expression code to resolve
  66                 ///   a name against a parameter.
  67                 /// </summary>
  68
  69                 // FIXME: This is very ugly and it's very hard to reset it correctly
  70                 // on all places, especially when some parameters are autogenerated.
  71                 ParametersCompiled current_local_parameters;
  72
  73                 bool parsing_anonymous_method;
  74
  75                 bool async_block;
  76
  77                 ///
  78                 /// An out-of-band stack.
  79                 ///
  80                 Stack<object> oob_stack;
  81
  82                 ///
  83                 /// Controls the verbosity of the errors produced by the parser
  84                 ///
  85                 int yacc_verbose_flag;
  86
  87                 ///
  88                 /// Used by the interactive shell, flags whether EOF was reached
  89                 /// and an error was produced
  90                 ///
  91                 public bool UnexpectedEOF;
  92
  93                 ///
  94                 /// The current file.
  95                 ///
  96                 readonly CompilationSourceFile file;
  97
  98                 ///
  99                 /// Temporary Xml documentation cache.
 100                 /// For enum types, we need one more temporary store.
 101                 ///
 102                 string tmpComment;
 103                 string enumTypeComment;
 104
 105                 /// Current attribute target
 106                 string current_attr_target;
 107
 108                 ParameterModifierType valid_param_mod;
 109
 110                 bool default_parameter_used;
 111
 112                 /// When using the interactive parser, this holds the
 113                 /// resulting expression
 114                 public Class InteractiveResult;
 115
 116                 //
 117                 // Keeps track of global data changes to undo on parser error
 118                 //
 119                 public Undo undo;
 120
 121                 bool? interactive_async;
 122
 123                 Stack<Linq.QueryBlock> linq_clause_blocks;
 124
 125                 ModuleContainer module;
 126
 127                 readonly CompilerContext compiler;
 128                 readonly LanguageVersion lang_version;
 129                 readonly bool doc_support;
 130                 readonly CompilerSettings settings;
 131                 readonly Report report;
 132
 133                 //
 134                 // Instead of allocating carrier array everytime we
 135                 // share the bucket for very common constructs which can never
 136                 // be recursive
 137                 //
 138                 List<Parameter> parameters_bucket;
 139
 140                 //
 141                 // Full AST support members
 142                 //
 143                 LocationsBag lbag;
 144                 List<Tuple<Modifiers, Location>> mod_locations;
 145                 Stack<Location> location_stack;
 146 %}
 147
 148 %token EOF
 149 %token NONE   /* This token is never returned by our lexer */
 150 %token ERROR            // This is used not by the parser, but by the tokenizer.
 151                         // do not remove.
 152
 153 /*
 154  *These are the C# keywords
 155  */
 156 %token FIRST_KEYWORD
 157 %token ABSTRACT
 158 %token AS
 159 %token ADD
 160 %token BASE
 161 %token BOOL
 162 %token BREAK
 163 %token BYTE
 164 %token CASE
 165 %token CATCH
 166 %token CHAR
 167 %token CHECKED
 168 %token CLASS
 169 %token CONST
 170 %token CONTINUE
 171 %token DECIMAL
 172 %token DEFAULT
 173 %token DELEGATE
 174 %token DO
 175 %token DOUBLE
 176 %token ELSE
 177 %token ENUM
 178 %token EVENT
 179 %token EXPLICIT
 180 %token EXTERN
 181 %token FALSE
 182 %token FINALLY
 183 %token FIXED
 184 %token FLOAT
 185 %token FOR
 186 %token FOREACH
 187 %token GOTO
 188 %token IF
 189 %token IMPLICIT
 190 %token IN
 191 %token INT
 192 %token INTERFACE
 193 %token INTERNAL
 194 %token IS
 195 %token LOCK
 196 %token LONG
 197 %token NAMESPACE
 198 %token NEW
 199 %token NULL
 200 %token OBJECT
 201 %token OPERATOR
 202 %token OUT
 203 %token OVERRIDE
 204 %token PARAMS
 205 %token PRIVATE
 206 %token PROTECTED
 207 %token PUBLIC
 208 %token READONLY
 209 %token REF
 210 %token RETURN
 211 %token REMOVE
 212 %token SBYTE
 213 %token SEALED
 214 %token SHORT
 215 %token SIZEOF
 216 %token STACKALLOC
 217 %token STATIC
 218 %token STRING
 219 %token STRUCT
 220 %token SWITCH
 221 %token THIS
 222 %token THROW
 223 %token TRUE
 224 %token TRY
 225 %token TYPEOF
 226 %token UINT
 227 %token ULONG
 228 %token UNCHECKED
 229 %token UNSAFE
 230 %token USHORT
 231 %token USING
 232 %token VIRTUAL
 233 %token VOID
 234 %token VOLATILE
 235 %token WHERE
 236 %token WHILE
 237 %token ARGLIST
 238 %token PARTIAL
 239 %token ARROW
 240 %token FROM
 241 %token FROM_FIRST
 242 %token JOIN
 243 %token ON
 244 %token EQUALS
 245 %token SELECT
 246 %token GROUP
 247 %token BY
 248 %token LET
 249 %token ORDERBY
 250 %token ASCENDING
 251 %token DESCENDING
 252 %token INTO
 253 %token INTERR_NULLABLE
 254 %token EXTERN_ALIAS
 255 %token REFVALUE
 256 %token REFTYPE
 257 %token MAKEREF
 258 %token ASYNC
 259 %token AWAIT
 260 %token INTERR_OPERATOR
 261 %token WHEN
 262 %token INTERPOLATED_STRING
 263 %token INTERPOLATED_STRING_END
 264
 265 /* C# keywords which are not really keywords */
 266 %token GET
 267 %token SET
 268
 269 %left LAST_KEYWORD
 270
 271 /* C# single character operators/punctuation. */
 272 %token OPEN_BRACE
 273 %token CLOSE_BRACE
 274 %token OPEN_BRACKET
 275 %token CLOSE_BRACKET
 276 %token OPEN_PARENS
 277 %token CLOSE_PARENS
 278
 279 %token DOT
 280 %token COMMA
 281 %token COLON
 282 %token SEMICOLON
 283 %token TILDE
 284
 285 %token PLUS
 286 %token MINUS
 287 %token BANG
 288 %token ASSIGN
 289 %token OP_LT
 290 %token OP_GT
 291 %token BITWISE_AND
 292 %token BITWISE_OR
 293 %token STAR
 294 %token PERCENT
 295 %token DIV
 296 %token CARRET
 297 %token INTERR
 298
 299 /* C# multi-character operators. */
 300 %token DOUBLE_COLON
 301 %token OP_INC
 302 %token OP_DEC
 303 %token OP_SHIFT_LEFT
 304 %token OP_SHIFT_RIGHT
 305 %token OP_LE
 306 %token OP_GE
 307 %token OP_EQ
 308 %token OP_NE
 309 %token OP_AND
 310 %token OP_OR
 311 %token OP_MULT_ASSIGN
 312 %token OP_DIV_ASSIGN
 313 %token OP_MOD_ASSIGN
 314 %token OP_ADD_ASSIGN
 315 %token OP_SUB_ASSIGN
 316 %token OP_SHIFT_LEFT_ASSIGN
 317 %token OP_SHIFT_RIGHT_ASSIGN
 318 %token OP_AND_ASSIGN
 319 %token OP_XOR_ASSIGN
 320 %token OP_OR_ASSIGN
 321 %token OP_PTR
 322 %token OP_COALESCING
 323
 324 /* Generics <,> tokens */
 325 %token OP_GENERICS_LT
 326 %token OP_GENERICS_LT_DECL
 327 %token OP_GENERICS_GT
 328
 329 %token LITERAL
 330
 331 %token IDENTIFIER
 332 %token OPEN_PARENS_LAMBDA
 333 %token OPEN_PARENS_CAST
 334 %token GENERIC_DIMENSION
 335 %token DEFAULT_COLON
 336 %token OPEN_BRACKET_EXPR
 337
 338 // Make the parser go into eval mode parsing (statements and compilation units).
 339 %token EVAL_STATEMENT_PARSER
 340 %token EVAL_COMPILATION_UNIT_PARSER
 341 %token EVAL_USING_DECLARATIONS_UNIT_PARSER
 342
 343 %token DOC_SEE
 344
 345 //
 346 // This token is generated to trigger the completion engine at this point
 347 //
 348 %token GENERATE_COMPLETION
 349
 350 //
 351 // This token is return repeatedly after the first GENERATE_COMPLETION
 352 // token is produced and before the final EOF
 353 //
 354 %token COMPLETE_COMPLETION
 355
 356 /* Add precedence rules to solve dangling else s/r conflict */
 357 %nonassoc IF
 358 %nonassoc ELSE
 359
 360 /* Define the operator tokens and their precedences */
 361 %right ASSIGN
 362 %right OP_COALESCING
 363 %right INTERR
 364 %left OP_OR
 365 %left OP_AND
 366 %left BITWISE_OR
 367 %left BITWISE_AND
 368 %left OP_SHIFT_LEFT OP_SHIFT_RIGHT
 369 %left PLUS MINUS
 370 %left STAR DIV PERCENT
 371 %right BANG CARRET UMINUS
 372 %nonassoc OP_INC OP_DEC
 373 %left OPEN_PARENS
 374 %left OPEN_BRACKET OPEN_BRACE
 375 %left DOT
 376
 377 %start compilation_unit
 378 %%
 379
 380 compilation_unit
 381         : outer_declaration opt_EOF
 382           {
 383                 Lexer.check_incorrect_doc_comment ();
 384           }
 385         | interactive_parsing  { Lexer.CompleteOnEOF = false; } opt_EOF
 386         | documentation_parsing
 387         ;
 388
 389 outer_declaration
 390         : opt_extern_alias_directives opt_using_directives
 391         | opt_extern_alias_directives opt_using_directives namespace_or_type_declarations opt_attributes
 392           {
 393                 if ($4 != null) {
 394                         Attributes attrs = (Attributes) $4;
 395                         report.Error (1730, attrs.Attrs [0].Location,
 396                                 "Assembly and module attributes must precede all other elements except using clauses and extern alias declarations");
 397
 398                         current_namespace.UnattachedAttributes = attrs;
 399                 }
 400           }
 401         | opt_extern_alias_directives opt_using_directives attribute_sections
 402           {
 403                 Attributes attrs = (Attributes) $3;
 404                 if (attrs != null) {
 405                         foreach (var a in attrs.Attrs) {
 406                                 if (a.ExplicitTarget == "assembly" || a.ExplicitTarget == "module")
 407                                         continue;
 408
 409                                 if (a.ExplicitTarget == null)
 410                                         report.Error (-1671, a.Location, "Global attributes must have attribute target specified");
 411                         }
 412                 }
 413
 414                 module.AddAttributes ((Attributes) $3, current_namespace);
 415           }
 416         | error
 417           {
 418                 if (yyToken == Token.EXTERN_ALIAS)
 419                         report.Error (439, lexer.Location, "An extern alias declaration must precede all other elements");
 420                 else
 421                         Error_SyntaxError (yyToken);
 422           }
 423         ;
 424
 425 opt_EOF
 426         : /* empty */
 427         | EOF
 428         ;
 429
 430 extern_alias_directives
 431         : extern_alias_directive
 432         | extern_alias_directives extern_alias_directive
 433         ;
 434
 435 extern_alias_directive
 436         : EXTERN_ALIAS IDENTIFIER IDENTIFIER SEMICOLON
 437           {
 438                 var lt = (LocatedToken) $2;
 439                 string s = lt.Value;
 440                 if (s != "alias") {
 441                         syntax_error (lt.Location, "`alias' expected");
 442                 } else {
 443                         if (lang_version == LanguageVersion.ISO_1)
 444                                 FeatureIsNotAvailable (lt.Location, "external alias");
 445
 446                         lt = (LocatedToken) $3;
 447                         if (lt.Value == QualifiedAliasMember.GlobalAlias) {
 448                                 RootNamespace.Error_GlobalNamespaceRedefined (report, lt.Location);
 449                         }
 450
 451                         var na = new UsingExternAlias (new SimpleMemberName (lt.Value, lt.Location), GetLocation ($1));
 452                         current_namespace.AddUsing (na);
 453
 454                         lbag.AddLocation (na, GetLocation ($2), GetLocation ($4));
 455                 }
 456           }
 457         | EXTERN_ALIAS error
 458           {
 459                 Error_SyntaxError (yyToken);
 460           }
 461         ;
 462
 463 using_directives
 464         : using_directive
 465         | using_directives using_directive
 466         ;
 467
 468 using_directive
 469         : using_namespace
 470           {
 471                 if (doc_support)
 472                         Lexer.doc_state = XmlCommentState.Allowed;
 473           }
 474         ;
 475
 476 using_namespace
 477         : USING opt_static namespace_or_type_expr SEMICOLON
 478           {
 479                 UsingClause uc;
 480                 if ($2 != null) {
 481                         if (lang_version <= LanguageVersion.V_5)
 482                                 FeatureIsNotAvailable (GetLocation ($2), "using static");
 483
 484                         uc = new UsingType ((ATypeNameExpression) $3, GetLocation ($1));
 485                         lbag.AddLocation (uc, GetLocation ($2), GetLocation ($4));
 486                 } else {
 487                         uc = new UsingNamespace ((ATypeNameExpression) $3, GetLocation ($1));
 488                         lbag.AddLocation (uc, GetLocation ($4));
 489                 }
 490
 491                 current_namespace.AddUsing (uc);
 492           }
 493         | USING opt_static IDENTIFIER ASSIGN namespace_or_type_expr SEMICOLON
 494           {
 495                 var lt = (LocatedToken) $3;
 496                 if (lang_version != LanguageVersion.ISO_1 && lt.Value == "global") {
 497                         report.Warning (440, 2, lt.Location,
 498                          "An alias named `global' will not be used when resolving `global::'. The global namespace will be used instead");
 499                 }
 500
 501                 if ($2 != null) {
 502                         report.Error (8085, GetLocation ($2), "A `using static' directive cannot be used to declare an alias");
 503                 }
 504
 505                 var un = new UsingAliasNamespace (new SimpleMemberName (lt.Value, lt.Location), (ATypeNameExpression) $5, GetLocation ($1));
 506                 current_namespace.AddUsing (un);
 507
 508                 lbag.AddLocation (un, GetLocation ($4), GetLocation ($6));
 509           }
 510         | USING error
 511          {
 512                 Error_SyntaxError (yyToken);
 513                 $$ = null;
 514          }
 515         ;
 516
 517 opt_static
 518         :
 519         | STATIC
 520         ;
 521
 522 //
 523 // Strictly speaking, namespaces don't have attributes but
 524 // we parse global attributes along with namespace declarations and then
 525 // detach them
 526 //
 527 namespace_declaration
 528         : opt_attributes NAMESPACE namespace_name
 529           {
 530                 Attributes attrs = (Attributes) $1;
 531                 var name = (MemberName) $3;
 532                 if (attrs != null) {
 533                         bool valid_global_attrs = true;
 534                         if ((current_namespace.DeclarationFound || current_namespace != file)) {
 535                                 valid_global_attrs = false;
 536                         } else {
 537                                 foreach (var a in attrs.Attrs) {
 538                                         if (a.ExplicitTarget == "assembly" || a.ExplicitTarget == "module")
 539                                                 continue;
 540
 541                                         valid_global_attrs = false;
 542                                         break;
 543                                 }
 544                         }
 545
 546                         if (!valid_global_attrs)
 547                                 report.Error (1671, name.Location, "A namespace declaration cannot have modifiers or attributes");
 548                 }
 549
 550                 module.AddAttributes (attrs, current_namespace);
 551
 552                 var ns = new NamespaceContainer (name, current_namespace);
 553                 current_namespace.AddTypeContainer (ns);
 554                 current_container = current_namespace = ns;
 555           }
 556           OPEN_BRACE
 557           {
 558                 if (doc_support)
 559                         Lexer.doc_state = XmlCommentState.Allowed;
 560           }
 561           opt_extern_alias_directives opt_using_directives opt_namespace_or_type_declarations CLOSE_BRACE opt_semicolon_error
 562           {
 563                 if ($11 != null)
 564                         lbag.AddLocation (current_container, GetLocation ($2), GetLocation ($5), GetLocation ($10), GetLocation ($11));
 565                 else
 566                         lbag.AddLocation (current_container, GetLocation ($2), GetLocation ($5), GetLocation ($10));
 567
 568                 current_container = current_namespace = current_namespace.Parent;
 569           }
 570         | opt_attributes NAMESPACE namespace_name
 571           {
 572                 report.Error (1514, lexer.Location, "Unexpected symbol `{0}', expecting `.' or `{{'", GetSymbolName (yyToken));
 573
 574                 var name = (MemberName) $3;
 575                 var ns = new NamespaceContainer (name, current_namespace);
 576                 lbag.AddLocation (ns, GetLocation ($2));
 577                 current_namespace.AddTypeContainer (ns);
 578           }
 579         ;
 580
 581 opt_semicolon_error
 582         : /* empty */
 583         | SEMICOLON
 584         | error
 585           {
 586                 Error_SyntaxError (yyToken);
 587                 $$ = null;
 588           }
 589         ;
 590
 591 namespace_name
 592         : IDENTIFIER
 593           {
 594                 var lt = (LocatedToken) $1;
 595                 $$ = new MemberName (lt.Value, lt.Location);
 596           }
 597         | namespace_name DOT IDENTIFIER
 598           {
 599                 var lt = (LocatedToken) $3;
 600                 $$ = new MemberName ((MemberName) $1, lt.Value, lt.Location);
 601                 lbag.AddLocation ($$, GetLocation ($2));
 602           }
 603         | error
 604           {
 605                 Error_SyntaxError (yyToken);
 606                 $$ = new MemberName ("<invalid>", lexer.Location);
 607           }
 608         ;
 609
 610 opt_semicolon
 611         : /* empty */
 612         | SEMICOLON
 613         ;
 614
 615 opt_comma
 616         : /* empty */
 617         | COMMA
 618         ;
 619
 620 opt_using_directives
 621         : /* empty */
 622         | using_directives
 623         ;
 624
 625 opt_extern_alias_directives
 626         : /* empty */
 627         | extern_alias_directives
 628         ;
 629
 630 opt_namespace_or_type_declarations
 631         : /* empty */
 632         | namespace_or_type_declarations
 633         ;
 634
 635 namespace_or_type_declarations
 636         : namespace_or_type_declaration
 637         | namespace_or_type_declarations namespace_or_type_declaration
 638         ;
 639
 640 namespace_or_type_declaration
 641         : type_declaration
 642           {
 643                 if ($1 != null) {
 644                         TypeContainer ds = (TypeContainer)$1;
 645
 646                         if ((ds.ModFlags & (Modifiers.PRIVATE | Modifiers.PROTECTED)) != 0){
 647                                 report.Error (1527, ds.Location,
 648                                 "Namespace elements cannot be explicitly declared as private, protected or protected internal");
 649                         }
 650
 651                         // Here is a trick, for explicit attributes we don't know where they belong to until
 652                         // we parse succeeding declaration hence we parse them as normal and re-attach them
 653                         // when we know whether they are global (assembly:, module:) or local (type:).
 654                         if (ds.OptAttributes != null) {
 655                                 ds.OptAttributes.ConvertGlobalAttributes (ds, current_namespace, !current_namespace.DeclarationFound && current_namespace == file);
 656                         }
 657                 }
 658                 current_namespace.DeclarationFound = true;
 659           }
 660         | namespace_declaration
 661           {
 662                 current_namespace.DeclarationFound = true;
 663           }
 664         | attribute_sections CLOSE_BRACE {
 665                 current_namespace.UnattachedAttributes = (Attributes) $1;
 666                 report.Error (1518, lexer.Location, "Attributes must be attached to class, delegate, enum, interface or struct");
 667                 lexer.putback ('}');
 668           }
 669         ;
 670
 671 type_declaration
 672         : class_declaration
 673         | struct_declaration
 674         | interface_declaration
 675         | enum_declaration
 676         | delegate_declaration
 677 //
 678 // Enable this when we have handled all errors, because this acts as a generic fallback
 679 //
 680 //      | error {
 681 //              Console.WriteLine ("Token=" + yyToken);
 682 //              report.Error (1518, GetLocation ($1), "Expected class, struct, interface, enum or delegate");
 683 //        }
 684         ;
 685
 686 //
 687 // Attributes
 688 //
 689
 690 opt_attributes
 691         : /* empty */
 692         | attribute_sections
 693     ;
 694
 695 attribute_sections
 696         : attribute_section
 697           {
 698                 var sect = (List<Attribute>) $1;
 699                 $$ = new Attributes (sect);
 700           }
 701         | attribute_sections attribute_section
 702           {
 703                 Attributes attrs = $1 as Attributes;
 704                 var sect = (List<Attribute>) $2;
 705                 if (attrs == null)
 706                         attrs = new Attributes (sect);
 707                 else if (sect != null)
 708                         attrs.AddAttributes (sect);
 709                 $$ = attrs;
 710           }
 711         ;
 712
 713 attribute_section
 714         : OPEN_BRACKET
 715           {
 716                 PushLocation (GetLocation ($1));
 717                 lexer.parsing_attribute_section = true;
 718           }
 719           attribute_section_cont
 720           {
 721                 lexer.parsing_attribute_section = false;
 722                 $$ = $3;
 723           }
 724         ;
 725
 726 attribute_section_cont
 727         : attribute_target COLON
 728           {
 729                 current_attr_target = (string) $1;
 730                 if (current_attr_target == "assembly" || current_attr_target == "module") {
 731                         Lexer.check_incorrect_doc_comment ();
 732                 }
 733           }
 734           attribute_list opt_comma CLOSE_BRACKET
 735           {
 736                 // when attribute target is invalid
 737                 if (current_attr_target == string.Empty)
 738                         $$ = new List<Attribute> (0);
 739                 else
 740                         $$ = $4;
 741
 742                 lbag.InsertLocation ($$, 0, PopLocation ());
 743                 if ($5 != null) {
 744                         lbag.AddLocation ($$, GetLocation ($2), GetLocation ($5), GetLocation ($6));
 745                 } else {
 746                         lbag.AddLocation ($$, GetLocation ($2), GetLocation ($6));
 747                 }
 748
 749                 current_attr_target = null;
 750                 lexer.parsing_attribute_section = false;
 751           }
 752         | attribute_list opt_comma CLOSE_BRACKET
 753           {
 754                 $$ = $1;
 755
 756                 lbag.InsertLocation ($$, 0, PopLocation ());
 757                 if ($2 != null) {
 758                         lbag.AddLocation ($$, GetLocation($2), GetLocation ($3));
 759                 } else {
 760                         lbag.AddLocation ($$, GetLocation($3));
 761                 }
 762           }
 763         | IDENTIFIER error
 764           {
 765                 Error_SyntaxError (yyToken);
 766
 767                 var lt = (LocatedToken) $1;
 768                 var tne = new SimpleName (lt.Value, null, lt.Location);
 769
 770                 $$ = new List<Attribute> () {
 771                         new Attribute (null, tne, null, GetLocation ($1), false)
 772                 };
 773           }
 774         | error
 775           {
 776                 if (CheckAttributeTarget (yyToken, GetTokenName (yyToken), GetLocation ($1)).Length > 0)
 777                         Error_SyntaxError (yyToken);
 778
 779                 $$ = null;
 780           }
 781         ;
 782
 783 attribute_target
 784         : IDENTIFIER
 785           {
 786                 var lt = (LocatedToken) $1;
 787                 $$ = CheckAttributeTarget (yyToken, lt.Value, lt.Location);
 788           }
 789         | EVENT  { $$ = "event"; }
 790         | RETURN { $$ = "return"; }
 791         ;
 792
 793 attribute_list
 794         : attribute
 795           {
 796                 $$ = new List<Attribute> (4) { (Attribute) $1 };
 797           }
 798         | attribute_list COMMA attribute
 799           {
 800                 var attrs = (List<Attribute>) $1;
 801                 if (attrs != null) {
 802                         attrs.Add ((Attribute) $3);
 803                         lbag.AppendTo (attrs, GetLocation ($2));
 804                 }
 805
 806                 $$ = attrs;
 807           }
 808         ;
 809
 810 attribute
 811         : attribute_name
 812           {
 813                 ++lexer.parsing_block;
 814           }
 815           opt_attribute_arguments
 816           {
 817                 --lexer.parsing_block;
 818
 819                 var tne = (ATypeNameExpression) $1;
 820                 if (tne.HasTypeArguments) {
 821                         report.Error (404, tne.Location, "Attributes cannot be generic");
 822                 }
 823
 824                 $$ = new Attribute (current_attr_target, tne, (Arguments[]) $3, GetLocation ($1), lexer.IsEscapedIdentifier (tne));
 825           }
 826         ;
 827
 828 attribute_name
 829         : namespace_or_type_expr
 830         ;
 831
 832 opt_attribute_arguments
 833         : /* empty */   { $$ = null; }
 834         | OPEN_PARENS attribute_arguments CLOSE_PARENS
 835           {
 836                 $$ = $2;
 837           }
 838         ;
 839
 840
 841 attribute_arguments
 842         : /* empty */           { $$ = null; }
 843         | positional_or_named_argument
 844           {
 845                 Arguments a = new Arguments (4);
 846                 a.Add ((Argument) $1);
 847                 $$ = new Arguments [] { a, null };
 848           }
 849         | named_attribute_argument
 850           {
 851                 Arguments a = new Arguments (4);
 852                 a.Add ((Argument) $1);
 853                 $$ = new Arguments [] { null, a };
 854           }
 855     | attribute_arguments COMMA positional_or_named_argument
 856           {
 857                 Arguments[] o = (Arguments[]) $1;
 858                 if (o [1] != null) {
 859                         report.Error (1016, ((Argument) $3).Expr.Location, "Named attribute arguments must appear after the positional arguments");
 860                         o [0] = new Arguments (4);
 861                 }
 862
 863                 Arguments args = ((Arguments) o [0]);
 864                 if (args.Count > 0 && !($3 is NamedArgument) && args [args.Count - 1] is NamedArgument)
 865                         Error_NamedArgumentExpected ((NamedArgument) args [args.Count - 1]);
 866
 867                 args.Add ((Argument) $3);
 868           }
 869     | attribute_arguments COMMA named_attribute_argument
 870           {
 871                 Arguments[] o = (Arguments[]) $1;
 872                 if (o [1] == null) {
 873                         o [1] = new Arguments (4);
 874                 }
 875
 876                 ((Arguments) o [1]).Add ((Argument) $3);
 877           }
 878     ;
 879
 880 positional_or_named_argument
 881         : expression
 882           {
 883                 $$ = new Argument ((Expression) $1);
 884           }
 885         | named_argument
 886         | error
 887           {
 888                 Error_SyntaxError (yyToken);
 889                 $$ = null;
 890           }
 891         ;
 892
 893 named_attribute_argument
 894         : IDENTIFIER ASSIGN
 895           {
 896                 ++lexer.parsing_block;
 897           }
 898           expression
 899           {
 900                 --lexer.parsing_block;
 901                 var lt = (LocatedToken) $1;
 902                 $$ = new NamedArgument (lt.Value, lt.Location, (Expression) $4);
 903                 lbag.AddLocation ($$, GetLocation($2));
 904           }
 905         ;
 906
 907 named_argument
 908         : identifier_inside_body COLON opt_named_modifier named_argument_expr
 909           {
 910                 if (lang_version <= LanguageVersion.V_3)
 911                         FeatureIsNotAvailable (GetLocation ($1), "named argument");
 912
 913                 // Avoid boxing in common case (no modifier)
 914                 var arg_mod = $3 == null ? Argument.AType.None : (Argument.AType) $3;
 915
 916                 var lt = (LocatedToken) $1;
 917                 $$ = new NamedArgument (lt.Value, lt.Location, (Expression) $4, arg_mod);
 918                 lbag.AddLocation ($$, GetLocation($2));
 919           }
 920         ;
 921
 922 named_argument_expr
 923         : expression_or_error
 924 //      | declaration_expression
 925         ;
 926
 927 opt_named_modifier
 928         : /* empty */   { $$ = null; }
 929         | REF
 930           {
 931                 $$ = Argument.AType.Ref;
 932           }
 933         | OUT
 934           {
 935                 $$ = Argument.AType.Out;
 936           }
 937         ;
 938
 939 opt_class_member_declarations
 940         : /* empty */
 941         | class_member_declarations
 942         ;
 943
 944 class_member_declarations
 945         : class_member_declaration
 946           {
 947                 lexer.parsing_modifiers = true;
 948                 lexer.parsing_block = 0;
 949           }
 950         | class_member_declarations class_member_declaration
 951           {
 952                 lexer.parsing_modifiers = true;
 953                 lexer.parsing_block = 0;
 954           }
 955         ;
 956
 957 class_member_declaration
 958         : constant_declaration
 959         | field_declaration
 960         | method_declaration
 961         | property_declaration
 962         | event_declaration
 963         | indexer_declaration
 964         | operator_declaration
 965         | constructor_declaration
 966         | primary_constructor_body
 967         | destructor_declaration
 968         | type_declaration
 969         | attributes_without_members
 970         | incomplete_member
 971         | error
 972           {
 973                 report.Error (1519, lexer.Location, "Unexpected symbol `{0}' in class, struct, or interface member declaration",
 974                         GetSymbolName (yyToken));
 975                 $$ = null;
 976                 lexer.parsing_generic_declaration = false;
 977           }
 978         ;
 979
 980 primary_constructor_body
 981         : OPEN_BRACE
 982           {
 983                 current_local_parameters = current_type.PrimaryConstructorParameters;
 984                 if (current_local_parameters == null) {
 985                         report.Error (9010, GetLocation ($1), "Primary constructor body is not allowed");
 986                         current_local_parameters = ParametersCompiled.EmptyReadOnlyParameters;
 987                 }
 988
 989                 ++lexer.parsing_block;
 990                 start_block (GetLocation ($1));
 991           }
 992           opt_statement_list block_end
 993           {
 994                 current_local_parameters = null;
 995                 var t = current_type as ClassOrStruct;
 996                 if (t != null) {
 997                         var b = (ToplevelBlock) $4;
 998                         if (t.PrimaryConstructorBlock != null) {
 999                                 report.Error (8041, b.StartLocation, "Primary constructor already has a body");
1000                         } else {
1001                                 t.PrimaryConstructorBlock = b;
1002                         }
1003                 }
1004           }
1005         ;
1006
1007 struct_declaration
1008         : opt_attributes
1009           opt_modifiers
1010           opt_partial
1011           STRUCT
1012           {
1013           }
1014           type_declaration_name
1015           {
1016                 lexer.ConstraintsParsing = true;
1017                 valid_param_mod = ParameterModifierType.PrimaryConstructor;
1018                 push_current_container (new Struct (current_container, (MemberName) $6, (Modifiers) $2, (Attributes) $1), $3);
1019           }
1020           opt_primary_parameters
1021           opt_class_base
1022           opt_type_parameter_constraints_clauses
1023           {
1024                 valid_param_mod = 0;
1025                 lexer.ConstraintsParsing = false;
1026
1027                 if ($8 != null)
1028                         current_type.PrimaryConstructorParameters = (ParametersCompiled) $8;
1029
1030                 if ($10 != null)
1031                         current_container.SetConstraints ((List<Constraints>) $10);
1032
1033                 if (doc_support)
1034                         current_container.PartialContainer.DocComment = Lexer.consume_doc_comment ();
1035
1036                 lbag.AddMember (current_container, mod_locations, GetLocation ($4));
1037
1038                 lexer.parsing_modifiers = true;
1039           }
1040           OPEN_BRACE
1041           {
1042                 if (doc_support)
1043                         Lexer.doc_state = XmlCommentState.Allowed;
1044           }
1045           opt_class_member_declarations CLOSE_BRACE
1046           {
1047                 --lexer.parsing_declaration;
1048                 if (doc_support)
1049                         Lexer.doc_state = XmlCommentState.Allowed;
1050           }
1051           opt_semicolon
1052           {
1053                 if ($16 == null) {
1054                         lbag.AppendToMember (current_container, GetLocation ($12), GetLocation ($15));
1055                 } else {
1056                         lbag.AppendToMember (current_container, GetLocation ($12), GetLocation ($15), GetLocation ($17));
1057                 }
1058                 $$ = pop_current_class ();
1059           }
1060         | opt_attributes opt_modifiers opt_partial STRUCT error
1061           {
1062                 Error_SyntaxError (yyToken);
1063           }
1064         ;
1065
1066 constant_declaration
1067         : opt_attributes
1068           opt_modifiers
1069           CONST type IDENTIFIER
1070           {
1071                 var lt = (LocatedToken) $5;
1072                 var mod = (Modifiers) $2;
1073                 current_field = new Const (current_type, (FullNamedExpression) $4, mod, new MemberName (lt.Value, lt.Location), (Attributes) $1);
1074                 current_type.AddMember (current_field);
1075
1076                 if ((mod & Modifiers.STATIC) != 0) {
1077                         report.Error (504, current_field.Location, "The constant `{0}' cannot be marked static", current_field.GetSignatureForError ());
1078                 }
1079
1080                 $$ = current_field;
1081           }
1082           constant_initializer opt_constant_declarators SEMICOLON
1083           {
1084                 if (doc_support) {
1085                         current_field.DocComment = Lexer.consume_doc_comment ();
1086                         Lexer.doc_state = XmlCommentState.Allowed;
1087                 }
1088
1089                 current_field.Initializer = (ConstInitializer) $7;
1090                 lbag.AddMember (current_field, mod_locations, GetLocation ($3), GetLocation ($9));
1091                 current_field = null;
1092           }
1093         | opt_attributes
1094           opt_modifiers
1095           CONST type error
1096           {
1097                 Error_SyntaxError (yyToken);
1098
1099                 current_type.AddMember (new Const (current_type, (FullNamedExpression) $4, (Modifiers) $2, MemberName.Null, (Attributes) $1));
1100           }
1101         ;
1102
1103 opt_constant_declarators
1104         : /* empty */
1105         | constant_declarators
1106         ;
1107
1108 constant_declarators
1109         : constant_declarator
1110           {
1111                 current_field.AddDeclarator ((FieldDeclarator) $1);
1112           }
1113         | constant_declarators constant_declarator
1114           {
1115                 current_field.AddDeclarator ((FieldDeclarator) $2);
1116           }
1117         ;
1118
1119 constant_declarator
1120         : COMMA IDENTIFIER constant_initializer
1121           {
1122                 var lt = (LocatedToken) $2;
1123                 $$ = new FieldDeclarator (new SimpleMemberName (lt.Value, lt.Location), (ConstInitializer) $3);
1124                 lbag.AddLocation ($$, GetLocation ($1));
1125           }
1126         ;
1127
1128 constant_initializer
1129         : ASSIGN
1130           {
1131                 ++lexer.parsing_block;
1132           }
1133           constant_initializer_expr
1134           {
1135                 --lexer.parsing_block;
1136                 $$ = new ConstInitializer (current_field, (Expression) $3, GetLocation ($1));
1137           }
1138         | error
1139           {
1140                 report.Error (145, lexer.Location, "A const field requires a value to be provided");
1141                 $$ = null;
1142           }
1143         ;
1144
1145 constant_initializer_expr
1146         : constant_expression
1147         | array_initializer
1148         ;
1149
1150 field_declaration
1151         : opt_attributes
1152           opt_modifiers
1153           member_type IDENTIFIER
1154           {
1155                 lexer.parsing_generic_declaration = false;
1156
1157                 FullNamedExpression type = (FullNamedExpression) $3;
1158                 if (type.Type != null && type.Type.Kind == MemberKind.Void)
1159                         report.Error (670, GetLocation ($3), "Fields cannot have void type");
1160
1161                 var lt = (LocatedToken) $4;
1162                 current_field = new Field (current_type, type, (Modifiers) $2, new MemberName (lt.Value, lt.Location), (Attributes) $1);
1163                 current_type.AddField (current_field);
1164                 $$ = current_field;
1165           }
1166           opt_field_initializer
1167           opt_field_declarators
1168           SEMICOLON
1169           {
1170                 if (doc_support) {
1171                         current_field.DocComment = Lexer.consume_doc_comment ();
1172                         Lexer.doc_state = XmlCommentState.Allowed;
1173                 }
1174
1175                 lbag.AddMember (current_field, mod_locations, GetLocation ($8));
1176                 $$ = current_field;
1177                 current_field = null;
1178           }
1179         | opt_attributes
1180           opt_modifiers
1181           FIXED simple_type IDENTIFIER
1182           {
1183                 if (lang_version < LanguageVersion.ISO_2)
1184                         FeatureIsNotAvailable (GetLocation ($3), "fixed size buffers");
1185
1186                 var lt = (LocatedToken) $5;
1187                 current_field = new FixedField (current_type, (FullNamedExpression) $4, (Modifiers) $2,
1188                         new MemberName (lt.Value, lt.Location), (Attributes) $1);
1189
1190                 current_type.AddField (current_field);
1191           }
1192           fixed_field_size opt_fixed_field_declarators SEMICOLON
1193           {
1194                 if (doc_support) {
1195                         current_field.DocComment = Lexer.consume_doc_comment ();
1196                         Lexer.doc_state = XmlCommentState.Allowed;
1197             }
1198
1199                 current_field.Initializer = (ConstInitializer) $7;
1200                 lbag.AddMember (current_field, mod_locations, GetLocation ($9));
1201                 $$ = current_field;
1202             current_field = null;
1203           }
1204         | opt_attributes
1205           opt_modifiers
1206           FIXED simple_type error
1207           SEMICOLON
1208           {
1209                 report.Error (1641, GetLocation ($5), "A fixed size buffer field must have the array size specifier after the field name");
1210           }
1211         ;
1212
1213 opt_field_initializer
1214         : /* empty */
1215         | ASSIGN
1216           {
1217                 ++lexer.parsing_block;
1218                 current_local_parameters = ParametersCompiled.EmptyReadOnlyParameters;
1219                 start_block (GetLocation ($1));
1220           }
1221           variable_initializer
1222           {
1223                 --lexer.parsing_block;
1224                 current_field.Initializer = (Expression) $3;
1225                 lbag.AppendToMember (current_field, GetLocation ($1));
1226                 end_block (lexer.Location);
1227                 current_local_parameters = null;
1228           }
1229         ;
1230
1231 opt_field_declarators
1232         : /* empty */
1233         | field_declarators
1234         ;
1235
1236 field_declarators
1237         : field_declarator
1238           {
1239                 current_field.AddDeclarator ((FieldDeclarator) $1);
1240           }
1241         | field_declarators field_declarator
1242           {
1243                 current_field.AddDeclarator ((FieldDeclarator) $2);
1244           }
1245         ;
1246
1247 field_declarator
1248         : COMMA IDENTIFIER
1249           {
1250                 var lt = (LocatedToken) $2;
1251                 $$ = new FieldDeclarator (new SimpleMemberName (lt.Value, lt.Location), null);
1252                 lbag.AddLocation ($$, GetLocation ($1));
1253           }
1254         | COMMA IDENTIFIER ASSIGN
1255           {
1256                 ++lexer.parsing_block;
1257           }
1258           variable_initializer
1259           {
1260                 --lexer.parsing_block;
1261                 var lt = (LocatedToken) $2;
1262                 $$ = new FieldDeclarator (new SimpleMemberName (lt.Value, lt.Location), (Expression) $5);
1263                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($3));
1264           }
1265         ;
1266
1267 opt_fixed_field_declarators
1268         : /* empty */
1269         | fixed_field_declarators
1270         ;
1271
1272 fixed_field_declarators
1273         : fixed_field_declarator
1274           {
1275                 current_field.AddDeclarator ((FieldDeclarator) $1);
1276           }
1277         | fixed_field_declarators fixed_field_declarator
1278           {
1279                 current_field.AddDeclarator ((FieldDeclarator) $2);
1280           }
1281         ;
1282
1283 fixed_field_declarator
1284         : COMMA IDENTIFIER fixed_field_size
1285           {
1286                 var lt = (LocatedToken) $2;
1287                 $$ = new FieldDeclarator (new SimpleMemberName (lt.Value, lt.Location), (ConstInitializer) $3);
1288                 lbag.AddLocation ($$, GetLocation ($1));
1289           }
1290         ;
1291
1292 fixed_field_size
1293         : OPEN_BRACKET
1294           {
1295                 ++lexer.parsing_block;
1296           }
1297           expression CLOSE_BRACKET
1298           {
1299                 --lexer.parsing_block;
1300                 $$ = new ConstInitializer (current_field, (Expression) $3, GetLocation ($1));
1301                 lbag.AddLocation ($$, GetLocation ($4));
1302           }
1303         | OPEN_BRACKET error
1304           {
1305                 report.Error (443, lexer.Location, "Value or constant expected");
1306                 $$ = null;
1307           }
1308         ;
1309
1310 variable_initializer
1311         : expression
1312         | array_initializer
1313         | error
1314           {
1315                 // It has to be here for the parent to safely restore artificial block
1316                 Error_SyntaxError (yyToken);
1317                 $$ = null;
1318           }
1319         ;
1320
1321 method_declaration
1322         : method_header
1323           {
1324                 if (doc_support)
1325                         Lexer.doc_state = XmlCommentState.NotAllowed;
1326
1327                 // Was added earlier in the case of body being eof for full ast
1328           }
1329           method_body_expression_block
1330           {
1331                 Method method = (Method) $1;
1332                 method.Block = (ToplevelBlock) $3;
1333                 async_block = false;
1334
1335                 if (method.Block == null) {
1336                         method.ParameterInfo.CheckParameters (method);
1337
1338                         if ((method.ModFlags & Modifiers.ASYNC) != 0) {
1339                                 report.Error (1994, method.Location, "`{0}': The async modifier can only be used with methods that have a body",
1340                                         method.GetSignatureForError ());
1341                         }
1342                 } else {
1343                         if (current_container.Kind == MemberKind.Interface) {
1344                                 report.Error (531, method.Location, "`{0}': interface members cannot have a definition",
1345                                         method.GetSignatureForError ());
1346                         }
1347                 }
1348
1349                 current_local_parameters = null;
1350
1351                 if (doc_support)
1352                         Lexer.doc_state = XmlCommentState.Allowed;
1353           }
1354         ;
1355
1356 method_header
1357         : opt_attributes
1358           opt_modifiers
1359           member_type
1360           method_declaration_name OPEN_PARENS
1361           {
1362                 valid_param_mod = ParameterModifierType.All;
1363           }
1364           opt_formal_parameter_list CLOSE_PARENS
1365           {
1366                 valid_param_mod = 0;
1367                 MemberName name = (MemberName) $4;
1368                 current_local_parameters = (ParametersCompiled) $7;
1369
1370                 var method = Method.Create (current_type, (FullNamedExpression) $3, (Modifiers) $2,
1371                                      name, current_local_parameters, (Attributes) $1);
1372
1373                 current_type.AddMember (method);
1374
1375                 async_block = (method.ModFlags & Modifiers.ASYNC) != 0;
1376
1377                 if (doc_support)
1378                         method.DocComment = Lexer.consume_doc_comment ();
1379
1380                 lbag.AddMember (method, mod_locations, GetLocation ($5), GetLocation ($8));
1381
1382                 $$ = method;
1383
1384                 lexer.ConstraintsParsing = true;
1385           }
1386           opt_type_parameter_constraints_clauses
1387           {
1388                 lexer.ConstraintsParsing = false;
1389
1390                 if ($10 != null) {
1391                         var method = (Method) $9;
1392                         method.SetConstraints ((List<Constraints>) $10);
1393                 }
1394
1395                 $$ = $9;
1396           }
1397         | opt_attributes
1398           opt_modifiers
1399           PARTIAL
1400           VOID
1401           {
1402                 lexer.parsing_generic_declaration = true;
1403           }
1404           method_declaration_name
1405           OPEN_PARENS
1406           {
1407                 lexer.parsing_generic_declaration = false;
1408                 valid_param_mod = ParameterModifierType.All;
1409           }
1410           opt_formal_parameter_list CLOSE_PARENS
1411           {
1412                 lexer.ConstraintsParsing = true;
1413           }
1414           opt_type_parameter_constraints_clauses
1415           {
1416                 lexer.ConstraintsParsing = false;
1417                 valid_param_mod = 0;
1418
1419                 MemberName name = (MemberName) $6;
1420                 current_local_parameters = (ParametersCompiled) $9;
1421
1422                 var modifiers = (Modifiers) $2;
1423                 modifiers |= Modifiers.PARTIAL;
1424
1425                 var method = Method.Create (current_type, new TypeExpression (compiler.BuiltinTypes.Void, GetLocation ($4)),
1426                                      modifiers, name, current_local_parameters, (Attributes) $1);
1427
1428                 current_type.AddMember (method);
1429
1430                 async_block = (method.ModFlags & Modifiers.ASYNC) != 0;
1431
1432                 if ($12 != null)
1433                         method.SetConstraints ((List<Constraints>) $12);
1434
1435                 if (doc_support)
1436                         method.DocComment = Lexer.consume_doc_comment ();
1437
1438                 StoreModifierLocation (Modifiers.PARTIAL, GetLocation ($3));
1439                 lbag.AddMember (method, mod_locations, GetLocation ($7), GetLocation ($10));
1440                 $$ = method;
1441           }
1442         | opt_attributes
1443           opt_modifiers
1444           member_type
1445           modifiers method_declaration_name OPEN_PARENS opt_formal_parameter_list CLOSE_PARENS
1446           {
1447                 MemberName name = (MemberName) $5;
1448                 report.Error (1585, name.Location,
1449                         "Member modifier `{0}' must precede the member type and name", ModifiersExtensions.Name ((Modifiers) $4));
1450
1451                 var method = Method.Create (current_type, (FullNamedExpression) $3,
1452                                             0, name, (ParametersCompiled) $7, (Attributes) $1);
1453
1454                 current_type.AddMember (method);
1455
1456                 current_local_parameters = (ParametersCompiled) $7;
1457
1458                 if (doc_support)
1459                         method.DocComment = Lexer.consume_doc_comment ();
1460
1461                 $$ = method;
1462           }
1463         | opt_attributes
1464           opt_modifiers
1465           member_type
1466           method_declaration_name error
1467           {
1468                 Error_SyntaxError (yyToken);
1469                 current_local_parameters = ParametersCompiled.Undefined;
1470
1471                 MemberName name = (MemberName) $4;
1472                 var method = Method.Create (current_type, (FullNamedExpression) $3, (Modifiers) $2,
1473                                                                         name, current_local_parameters, (Attributes) $1);
1474
1475                 current_type.AddMember (method);
1476
1477                 if (doc_support)
1478                         method.DocComment = Lexer.consume_doc_comment ();
1479
1480                 $$ = method;
1481           }
1482         ;
1483
1484 method_body_expression_block
1485         : method_body
1486         | expression_block
1487         ;
1488
1489 method_body
1490         : block
1491         | SEMICOLON             { $$ = null; }
1492         ;
1493
1494 expression_block
1495         : ARROW
1496          {
1497                 if (lang_version < LanguageVersion.V_6) {
1498                         FeatureIsNotAvailable (GetLocation ($1), "expression bodied members");
1499                 }
1500
1501                 ++lexer.parsing_block;
1502                 start_block (GetLocation ($1));
1503          }
1504          expression SEMICOLON
1505          {
1506                 lexer.parsing_block = 0;
1507                 current_block.AddStatement (new ContextualReturn ((Expression) $3));
1508                 var b = end_block (GetLocation ($4));
1509                 b.IsCompilerGenerated = true;
1510                 $$ = b;
1511          }
1512         ;
1513
1514 opt_formal_parameter_list
1515         : /* empty */                   { $$ = ParametersCompiled.EmptyReadOnlyParameters; }
1516         | formal_parameter_list
1517         ;
1518
1519 formal_parameter_list
1520         : fixed_parameters
1521           {
1522                 var pars_list = (List<Parameter>) $1;
1523                 $$ = new ParametersCompiled (pars_list.ToArray ());
1524           }
1525         | fixed_parameters COMMA parameter_array
1526           {
1527                 var pars_list = (List<Parameter>) $1;
1528                 pars_list.Add ((Parameter) $3);
1529
1530                 $$ = new ParametersCompiled (pars_list.ToArray ());
1531           }
1532         | fixed_parameters COMMA arglist_modifier
1533           {
1534                 var pars_list = (List<Parameter>) $1;
1535                 pars_list.Add (new ArglistParameter (GetLocation ($3)));
1536                 $$ = new ParametersCompiled (pars_list.ToArray (), true);
1537           }
1538         | parameter_array COMMA error
1539           {
1540                 if ($1 != null)
1541                         report.Error (231, ((Parameter) $1).Location, "A params parameter must be the last parameter in a formal parameter list");
1542
1543                 $$ = new ParametersCompiled (new Parameter[] { (Parameter) $1 } );
1544           }
1545         | fixed_parameters COMMA parameter_array COMMA error
1546           {
1547                 if ($3 != null)
1548                         report.Error (231, ((Parameter) $3).Location, "A params parameter must be the last parameter in a formal parameter list");
1549
1550                 var pars_list = (List<Parameter>) $1;
1551                 pars_list.Add (new ArglistParameter (GetLocation ($3)));
1552
1553                 $$ = new ParametersCompiled (pars_list.ToArray (), true);
1554           }
1555         | arglist_modifier COMMA error
1556           {
1557                 report.Error (257, GetLocation ($1), "An __arglist parameter must be the last parameter in a formal parameter list");
1558
1559                 $$ = new ParametersCompiled (new Parameter [] { new ArglistParameter (GetLocation ($1)) }, true);
1560           }
1561         | fixed_parameters COMMA ARGLIST COMMA error
1562           {
1563                 report.Error (257, GetLocation ($3), "An __arglist parameter must be the last parameter in a formal parameter list");
1564
1565                 var pars_list = (List<Parameter>) $1;
1566                 pars_list.Add (new ArglistParameter (GetLocation ($3)));
1567
1568                 $$ = new ParametersCompiled (pars_list.ToArray (), true);
1569           }
1570         | parameter_array
1571           {
1572                 $$ = new ParametersCompiled (new Parameter[] { (Parameter) $1 } );
1573           }
1574         | arglist_modifier
1575           {
1576                 $$ = new ParametersCompiled (new Parameter [] { new ArglistParameter (GetLocation ($1)) }, true);
1577           }
1578         | error
1579           {
1580                 Error_SyntaxError (yyToken);
1581                 $$ = ParametersCompiled.EmptyReadOnlyParameters;
1582           }
1583         ;
1584
1585 fixed_parameters
1586         : fixed_parameter
1587           {
1588                 parameters_bucket.Clear ();
1589                 Parameter p = (Parameter) $1;
1590                 parameters_bucket.Add (p);
1591
1592                 default_parameter_used = p.HasDefaultValue;
1593                 $$ = parameters_bucket;
1594           }
1595         | fixed_parameters COMMA fixed_parameter
1596           {
1597                 var pars = (List<Parameter>) $1;
1598                 Parameter p = (Parameter) $3;
1599                 if (p != null) {
1600                         if (p.HasExtensionMethodModifier)
1601                                 report.Error (1100, p.Location, "The parameter modifier `this' can only be used on the first parameter");
1602                         else if (!p.HasDefaultValue && default_parameter_used)
1603                                 report.Error (1737, p.Location, "Optional parameter cannot precede required parameters");
1604
1605                         default_parameter_used |= p.HasDefaultValue;
1606                         pars.Add (p);
1607
1608                         lbag.AddLocation (p, GetLocation ($2));
1609                 }
1610
1611                 $$ = $1;
1612           }
1613         ;
1614
1615 fixed_parameter
1616         : opt_attributes
1617           opt_parameter_modifier
1618           parameter_type
1619           identifier_inside_body
1620           {
1621                 var lt = (LocatedToken) $4;
1622                 $$ = new Parameter ((FullNamedExpression) $3, lt.Value, (Parameter.Modifier) $2, (Attributes) $1, lt.Location);
1623           }
1624         | opt_attributes
1625           opt_parameter_modifier
1626           parameter_type
1627           identifier_inside_body OPEN_BRACKET CLOSE_BRACKET
1628           {
1629                 var lt = (LocatedToken) $4;
1630                 report.Error (1552, lt.Location, "Array type specifier, [], must appear before parameter name");
1631                 $$ = new Parameter ((FullNamedExpression) $3, lt.Value, (Parameter.Modifier) $2, (Attributes) $1, lt.Location);
1632           }
1633         | attribute_sections error
1634           {
1635                 Error_SyntaxError (yyToken);
1636                 Location l = GetLocation ($2);
1637                 $$ = new Parameter (null, null, Parameter.Modifier.NONE, (Attributes) $1, l);
1638           }
1639         | opt_attributes
1640           opt_parameter_modifier
1641           parameter_type
1642           error
1643           {
1644                 Error_SyntaxError (yyToken);
1645                 Location l = GetLocation ($4);
1646                 $$ = new Parameter ((FullNamedExpression) $3, null, (Parameter.Modifier) $2, (Attributes) $1, l);
1647           }
1648         | opt_attributes
1649           opt_parameter_modifier
1650           parameter_type
1651           identifier_inside_body
1652           ASSIGN
1653           {
1654                 ++lexer.parsing_block;
1655           }
1656           constant_expression
1657           {
1658                 --lexer.parsing_block;
1659                 if (lang_version <= LanguageVersion.V_3) {
1660                         FeatureIsNotAvailable (GetLocation ($5), "optional parameter");
1661                 }
1662
1663                 Parameter.Modifier mod = (Parameter.Modifier) $2;
1664                 if (mod != Parameter.Modifier.NONE) {
1665                         switch (mod) {
1666                         case Parameter.Modifier.REF:
1667                         case Parameter.Modifier.OUT:
1668                                 report.Error (1741, GetLocation ($2), "Cannot specify a default value for the `{0}' parameter",
1669                                         Parameter.GetModifierSignature (mod));
1670                                 break;
1671
1672                         case Parameter.Modifier.This:
1673                                 report.Error (1743, GetLocation ($2), "Cannot specify a default value for the `{0}' parameter",
1674                                         Parameter.GetModifierSignature (mod));
1675                                 break;
1676                         default:
1677                                 throw new NotImplementedException (mod.ToString ());
1678                         }
1679
1680                         mod = Parameter.Modifier.NONE;
1681                 }
1682
1683                 if ((valid_param_mod & ParameterModifierType.DefaultValue) == 0)
1684                         report.Error (1065, GetLocation ($5), "Optional parameter is not valid in this context");
1685
1686                 var lt = (LocatedToken) $4;
1687                 $$ = new Parameter ((FullNamedExpression) $3, lt.Value, mod, (Attributes) $1, lt.Location);
1688                 lbag.AddLocation ($$, GetLocation ($5));
1689
1690                 if ($7 != null)
1691                         ((Parameter) $$).DefaultValue = new DefaultParameterValueExpression ((Expression) $7);
1692           }
1693         ;
1694
1695 opt_parameter_modifier
1696         : /* empty */           { $$ = Parameter.Modifier.NONE; }
1697         | parameter_modifiers
1698         ;
1699
1700 parameter_modifiers
1701         : parameter_modifier
1702           {
1703                 $$ = $1;
1704           }
1705         | parameter_modifiers parameter_modifier
1706           {
1707                 Parameter.Modifier p2 = (Parameter.Modifier)$2;
1708                 Parameter.Modifier mod = (Parameter.Modifier)$1 | p2;
1709                 if (((Parameter.Modifier)$1 & p2) == p2) {
1710                         Error_DuplicateParameterModifier (lexer.Location, p2);
1711                 } else {
1712                         switch (mod & ~Parameter.Modifier.This) {
1713                                 case Parameter.Modifier.REF:
1714                                         report.Error (1101, lexer.Location, "The parameter modifiers `this' and `ref' cannot be used altogether");
1715                                         break;
1716                                 case Parameter.Modifier.OUT:
1717                                         report.Error (1102, lexer.Location, "The parameter modifiers `this' and `out' cannot be used altogether");
1718                                         break;
1719                                 default:
1720                                         report.Error (1108, lexer.Location, "A parameter cannot have specified more than one modifier");
1721                                         break;
1722                         }
1723                 }
1724                 $$ = mod;
1725           }
1726         ;
1727
1728 parameter_modifier
1729         : REF
1730           {
1731                 if ((valid_param_mod & ParameterModifierType.Ref) == 0)
1732                         Error_ParameterModifierNotValid ("ref", GetLocation ($1));
1733
1734                 $$ = Parameter.Modifier.REF;
1735           }
1736         | OUT
1737           {
1738                 if ((valid_param_mod & ParameterModifierType.Out) == 0)
1739                         Error_ParameterModifierNotValid ("out", GetLocation ($1));
1740
1741                 $$ = Parameter.Modifier.OUT;
1742           }
1743         | THIS
1744           {
1745                 if ((valid_param_mod & ParameterModifierType.This) == 0)
1746                         Error_ParameterModifierNotValid ("this", GetLocation ($1));
1747
1748                 if (lang_version <= LanguageVersion.ISO_2)
1749                         FeatureIsNotAvailable (GetLocation ($1), "extension methods");
1750
1751                 $$ = Parameter.Modifier.This;
1752           }
1753         ;
1754
1755 parameter_array
1756         : opt_attributes params_modifier type IDENTIFIER
1757           {
1758                 var lt = (LocatedToken) $4;
1759                 $$ = new ParamsParameter ((FullNamedExpression) $3, lt.Value, (Attributes) $1, lt.Location);
1760           }
1761         | opt_attributes params_modifier type IDENTIFIER ASSIGN constant_expression
1762           {
1763                 report.Error (1751, GetLocation ($2), "Cannot specify a default value for a parameter array");
1764
1765                 var lt = (LocatedToken) $4;
1766                 $$ = new ParamsParameter ((FullNamedExpression) $3, lt.Value, (Attributes) $1, lt.Location);
1767           }
1768         | opt_attributes params_modifier type error
1769           {
1770                 Error_SyntaxError (yyToken);
1771
1772                 $$ = new ParamsParameter ((FullNamedExpression) $3, null, (Attributes) $1, Location.Null);
1773           }
1774         ;
1775
1776 params_modifier
1777         : PARAMS
1778           {
1779                 if ((valid_param_mod & ParameterModifierType.Params) == 0)
1780                         report.Error (1670, (GetLocation ($1)), "The `params' modifier is not allowed in current context");
1781           }
1782         | PARAMS parameter_modifier
1783           {
1784                 Parameter.Modifier mod = (Parameter.Modifier)$2;
1785                 if ((mod & Parameter.Modifier.This) != 0) {
1786                         report.Error (1104, GetLocation ($1), "The parameter modifiers `this' and `params' cannot be used altogether");
1787                 } else {
1788                         report.Error (1611, GetLocation ($1), "The params parameter cannot be declared as ref or out");
1789                 }
1790           }
1791         | PARAMS params_modifier
1792           {
1793                 Error_DuplicateParameterModifier (GetLocation ($1), Parameter.Modifier.PARAMS);
1794           }
1795         ;
1796
1797 arglist_modifier
1798         : ARGLIST
1799           {
1800                 if ((valid_param_mod & ParameterModifierType.Arglist) == 0)
1801                         report.Error (1669, GetLocation ($1), "__arglist is not valid in this context");
1802           }
1803         ;
1804
1805 property_declaration
1806         : opt_attributes
1807           opt_modifiers
1808           member_type
1809           member_declaration_name
1810           {
1811                 lexer.parsing_generic_declaration = false;
1812                 if (doc_support)
1813                         tmpComment = Lexer.consume_doc_comment ();
1814           }
1815           OPEN_BRACE
1816           {
1817                 var type = (FullNamedExpression) $3;
1818                 current_property = new Property (current_type, type, (Modifiers) $2,
1819                         (MemberName) $4, (Attributes) $1);
1820
1821                 if (type.Type != null && type.Type.Kind == MemberKind.Void)
1822                         report.Error (547, GetLocation ($3), "`{0}': property or indexer cannot have void type", current_property.GetSignatureForError ());
1823
1824                 current_type.AddMember (current_property);
1825                 lbag.AddMember (current_property, mod_locations, GetLocation ($6));
1826
1827                 lexer.PropertyParsing = true;
1828           }
1829           accessor_declarations
1830           {
1831                 lexer.PropertyParsing = false;
1832
1833                 if (doc_support)
1834                         current_property.DocComment = ConsumeStoredComment ();
1835           }
1836           CLOSE_BRACE
1837           {
1838                 lbag.AppendToMember (current_property, GetLocation ($10));
1839                 lexer.parsing_modifiers = true;
1840           }
1841           opt_property_initializer
1842           {
1843                 current_property = null;
1844           }
1845         | opt_attributes
1846           opt_modifiers
1847           member_type
1848           member_declaration_name
1849           {
1850                 lexer.parsing_generic_declaration = false;
1851                 if (doc_support)
1852                         tmpComment = Lexer.consume_doc_comment ();
1853                 current_local_parameters = ParametersCompiled.EmptyReadOnlyParameters;
1854           }
1855           expression_block
1856           {
1857                 var type = (FullNamedExpression) $3;
1858                 var property = new Property (current_type, type, (Modifiers) $2,
1859                         (MemberName) $4, (Attributes) $1);
1860
1861                 property.Get = new Property.GetMethod (property, Modifiers.COMPILER_GENERATED, null, property.Location);
1862                 property.Get.Block = (ToplevelBlock) $6;
1863
1864                 if (current_container.Kind == MemberKind.Interface) {
1865                         report.Error (531, property.Get.Block.StartLocation,
1866                                 "`{0}': interface members cannot have a definition", property.GetSignatureForError ());
1867                 }
1868
1869                 if (type.Type != null && type.Type.Kind == MemberKind.Void)
1870                         report.Error (547, GetLocation ($3), "`{0}': property or indexer cannot have void type", property.GetSignatureForError ());
1871
1872                 if (doc_support)
1873                         property.DocComment = ConsumeStoredComment ();
1874
1875                 current_type.AddMember (property);
1876
1877                 current_local_parameters = null;
1878           }
1879         ;
1880
1881 opt_property_initializer
1882         : /* empty */
1883         | ASSIGN
1884           {
1885                 ++lexer.parsing_block;
1886                 current_local_parameters = ParametersCompiled.EmptyReadOnlyParameters;
1887                 start_block (GetLocation ($1));
1888           }
1889           property_initializer SEMICOLON
1890           {
1891                 --lexer.parsing_block;
1892                 ((Property)current_property).Initializer = (Expression) $3;
1893                 lbag.AppendToMember (current_property, GetLocation ($1), GetLocation ($4));
1894                 end_block (GetLocation ($4));
1895                 current_local_parameters = null;
1896
1897                 if (doc_support)
1898                         Lexer.doc_state = XmlCommentState.Allowed;
1899           }
1900         ;
1901
1902 property_initializer
1903         : expression
1904         | array_initializer
1905         ;
1906
1907 indexer_declaration
1908         : opt_attributes opt_modifiers
1909           member_type indexer_declaration_name OPEN_BRACKET
1910           {
1911                 valid_param_mod = ParameterModifierType.Params | ParameterModifierType.DefaultValue;
1912           }
1913           opt_formal_parameter_list CLOSE_BRACKET
1914           {
1915                 valid_param_mod = 0;
1916                 var type = (FullNamedExpression) $3;
1917                 Indexer indexer = new Indexer (current_type, type, (MemberName) $4, (Modifiers) $2, (ParametersCompiled) $7, (Attributes) $1);
1918
1919                 current_property = indexer;
1920
1921                 current_type.AddIndexer (indexer);
1922                 lbag.AddMember (current_property, mod_locations, GetLocation ($5), GetLocation ($8));
1923
1924                 if (type.Type != null && type.Type.Kind == MemberKind.Void)
1925                         report.Error (620, GetLocation ($3), "`{0}': indexer return type cannot be `void'", indexer.GetSignatureForError ());
1926
1927                 if (indexer.ParameterInfo.IsEmpty) {
1928                         report.Error (1551, GetLocation ($5), "Indexers must have at least one parameter");
1929                 }
1930
1931                 if (doc_support) {
1932                         tmpComment = Lexer.consume_doc_comment ();
1933                         Lexer.doc_state = XmlCommentState.Allowed;
1934                 }
1935
1936                 lexer.PropertyParsing = true;
1937                 current_local_parameters = (ParametersCompiled) $7;
1938           }
1939           indexer_body
1940           {
1941                 lexer.PropertyParsing = false;
1942                 current_local_parameters = null;
1943
1944                 if (current_property.AccessorFirst != null && current_property.AccessorFirst.Block == null)
1945                         ((Indexer) current_property).ParameterInfo.CheckParameters (current_property);
1946
1947                 if (doc_support)
1948                         current_property.DocComment = ConsumeStoredComment ();
1949
1950                 current_property = null;
1951           }
1952         ;
1953
1954 indexer_body
1955         : OPEN_BRACE accessor_declarations CLOSE_BRACE
1956           {
1957                 lbag.AppendToMember (current_property, GetLocation ($1), GetLocation ($3));
1958           }
1959         | expression_block
1960           {
1961                 current_property.Get = new Indexer.GetIndexerMethod (current_property, Modifiers.COMPILER_GENERATED, current_local_parameters, null, current_property.Location);
1962                 current_property.Get.Block = (ToplevelBlock) $1;
1963           }
1964         ;
1965
1966 accessor_declarations
1967         : get_accessor_declaration
1968         | get_accessor_declaration accessor_declarations
1969         | set_accessor_declaration
1970         | set_accessor_declaration accessor_declarations
1971         | error
1972           {
1973                 if (yyToken == Token.CLOSE_BRACE) {
1974                         report.Error (548, lexer.Location, "`{0}': property or indexer must have at least one accessor", current_property.GetSignatureForError ());
1975                 } else {
1976                         if (yyToken == Token.SEMICOLON)
1977                                 report.Error (1597, lexer.Location, "Semicolon after method or accessor block is not valid");
1978                         else
1979                                 report.Error (1014, GetLocation ($1), "A get or set accessor expected");
1980                 }
1981           }
1982         ;
1983
1984 get_accessor_declaration
1985         : opt_attributes opt_modifiers GET
1986           {
1987                 if ($2 != ModifierNone && lang_version == LanguageVersion.ISO_1) {
1988                         FeatureIsNotAvailable (GetLocation ($2), "access modifiers on properties");
1989                 }
1990
1991                 if (current_property.Get != null) {
1992                         report.Error (1007, GetLocation ($3), "Property accessor already defined");
1993                 }
1994
1995                 if (current_property is Indexer) {
1996                         current_property.Get = new Indexer.GetIndexerMethod (current_property, (Modifiers) $2, ((Indexer)current_property).ParameterInfo.Clone (),
1997                                 (Attributes) $1, GetLocation ($3));
1998                 } else {
1999                         current_property.Get = new Property.GetMethod (current_property,
2000                                 (Modifiers) $2, (Attributes) $1, GetLocation ($3));
2001                 }
2002
2003                 current_local_parameters = current_property.Get.ParameterInfo;
2004                 lbag.AddMember (current_property.Get, mod_locations);
2005                 lexer.PropertyParsing = false;
2006           }
2007           accessor_body
2008           {
2009                 if ($5 != null) {
2010                         current_property.Get.Block = (ToplevelBlock) $5;
2011
2012                         if (current_container.Kind == MemberKind.Interface) {
2013                                 report.Error (531, current_property.Get.Block.StartLocation,
2014                                         "`{0}': interface members cannot have a definition", current_property.Get.GetSignatureForError ());
2015                         }
2016                 }
2017
2018                 current_local_parameters = null;
2019                 lexer.PropertyParsing = true;
2020
2021                 if (doc_support)
2022                         if (Lexer.doc_state == XmlCommentState.Error)
2023                                 Lexer.doc_state = XmlCommentState.NotAllowed;
2024           }
2025         ;
2026
2027 set_accessor_declaration
2028         : opt_attributes opt_modifiers SET
2029           {
2030                 if ($2 != ModifierNone && lang_version == LanguageVersion.ISO_1) {
2031                         FeatureIsNotAvailable (GetLocation ($2), "access modifiers on properties");
2032                 }
2033
2034                 if (current_property.Set != null) {
2035                         report.Error (1007, GetLocation ($3), "Property accessor already defined");
2036                 }
2037
2038                 if (current_property is Indexer) {
2039                         current_property.Set = new Indexer.SetIndexerMethod (current_property, (Modifiers) $2,
2040                                 ParametersCompiled.MergeGenerated (compiler,
2041                                 ((Indexer)current_property).ParameterInfo, true, new Parameter (
2042                                         current_property.TypeExpression, "value", Parameter.Modifier.NONE, null, GetLocation ($3)),
2043                                         null),
2044                                 (Attributes) $1, GetLocation ($3));
2045                 } else {
2046                         current_property.Set = new Property.SetMethod (current_property, (Modifiers) $2,
2047                                 ParametersCompiled.CreateImplicitParameter (current_property.TypeExpression, GetLocation ($3)),
2048                                 (Attributes) $1, GetLocation ($3));
2049                 }
2050
2051                 current_local_parameters = current_property.Set.ParameterInfo;
2052                 lbag.AddMember (current_property.Set, mod_locations);
2053                 lexer.PropertyParsing = false;
2054           }
2055           accessor_body
2056           {
2057                 if ($5 != null) {
2058                         current_property.Set.Block = (ToplevelBlock) $5;
2059
2060                         if (current_container.Kind == MemberKind.Interface) {
2061                                 report.Error (531, current_property.Set.Block.StartLocation,
2062                                         "`{0}': interface members cannot have a definition", current_property.Set.GetSignatureForError ());
2063                         }
2064                 }
2065
2066                 current_local_parameters = null;
2067                 lexer.PropertyParsing = true;
2068
2069                 if (doc_support
2070                         && Lexer.doc_state == XmlCommentState.Error)
2071                         Lexer.doc_state = XmlCommentState.NotAllowed;
2072           }
2073         ;
2074
2075 accessor_body
2076         : block
2077         | SEMICOLON
2078           {
2079                 // TODO: lbag
2080                 $$ = null;
2081           }
2082         | error
2083           {
2084                 Error_SyntaxError (1043, yyToken, "Invalid accessor body");
2085                 $$ = null;
2086           }
2087         ;
2088
2089 interface_declaration
2090         : opt_attributes
2091           opt_modifiers
2092           opt_partial
2093           INTERFACE
2094           {
2095           }
2096           type_declaration_name
2097           {
2098                 lexer.ConstraintsParsing = true;
2099                 push_current_container (new Interface (current_container, (MemberName) $6, (Modifiers) $2, (Attributes) $1), $3);
2100                 lbag.AddMember (current_container, mod_locations, GetLocation ($4));
2101           }
2102           opt_class_base
2103           opt_type_parameter_constraints_clauses
2104           {
2105                 lexer.ConstraintsParsing = false;
2106
2107                 if ($9 != null)
2108                         current_container.SetConstraints ((List<Constraints>) $9);
2109
2110                 if (doc_support) {
2111                         current_container.PartialContainer.DocComment = Lexer.consume_doc_comment ();
2112                         Lexer.doc_state = XmlCommentState.Allowed;
2113                 }
2114
2115                 lexer.parsing_modifiers = true;
2116           }
2117           OPEN_BRACE opt_interface_member_declarations CLOSE_BRACE
2118           {
2119                 --lexer.parsing_declaration;
2120                 if (doc_support)
2121                         Lexer.doc_state = XmlCommentState.Allowed;
2122           }
2123           opt_semicolon
2124           {
2125                 if ($15 == null) {
2126                         lbag.AppendToMember (current_container, GetLocation ($11), GetLocation ($13));
2127                 } else {
2128                         lbag.AppendToMember (current_container, GetLocation ($11), GetLocation ($13), GetLocation ($15));
2129                 }
2130                 $$ = pop_current_class ();
2131           }
2132         | opt_attributes opt_modifiers opt_partial INTERFACE error
2133           {
2134                 Error_SyntaxError (yyToken);
2135           }
2136         ;
2137
2138 opt_interface_member_declarations
2139         : /* empty */
2140         | interface_member_declarations
2141         ;
2142
2143 interface_member_declarations
2144         : interface_member_declaration
2145           {
2146                 lexer.parsing_modifiers = true;
2147                 lexer.parsing_block = 0;
2148           }
2149         | interface_member_declarations interface_member_declaration
2150           {
2151                 lexer.parsing_modifiers = true;
2152                 lexer.parsing_block = 0;
2153           }
2154         ;
2155
2156 interface_member_declaration
2157         : constant_declaration
2158           {
2159                 report.Error (525, GetLocation ($1), "Interfaces cannot contain fields or constants");
2160           }
2161         | field_declaration
2162           {
2163                 report.Error (525, GetLocation ($1), "Interfaces cannot contain fields or constants");
2164           }
2165         | method_declaration
2166         | property_declaration
2167         | event_declaration
2168         | indexer_declaration
2169         | operator_declaration
2170           {
2171                 report.Error (567, GetLocation ($1), "Interfaces cannot contain operators");
2172           }
2173         | constructor_declaration
2174           {
2175                 report.Error (526, GetLocation ($1), "Interfaces cannot contain contructors");
2176           }
2177         | type_declaration
2178           {
2179                 report.Error (524, GetLocation ($1), "Interfaces cannot declare classes, structs, interfaces, delegates, or enumerations");
2180           }
2181         ;
2182
2183 operator_declaration
2184         : opt_attributes opt_modifiers operator_declarator
2185           {
2186           }
2187           method_body_expression_block
2188           {
2189                 OperatorDeclaration decl = (OperatorDeclaration) $3;
2190                 if (decl != null) {
2191                         Operator op = new Operator (
2192                                 current_type, decl.optype, decl.ret_type, (Modifiers) $2,
2193                                 current_local_parameters,
2194                                 (ToplevelBlock) $5, (Attributes) $1, decl.location);
2195
2196                         if (op.Block == null)
2197                                 op.ParameterInfo.CheckParameters (op);
2198
2199                         if (doc_support) {
2200                                 op.DocComment = tmpComment;
2201                                 Lexer.doc_state = XmlCommentState.Allowed;
2202                         }
2203
2204                         // Note again, checking is done in semantic analysis
2205                         current_type.AddOperator (op);
2206
2207                         lbag.AddMember (op, mod_locations, lbag.GetLocations (decl));
2208                 }
2209
2210                 current_local_parameters = null;
2211           }
2212         ;
2213
2214 operator_type
2215         : type_expression_or_array
2216         | VOID
2217           {
2218                 report.Error (590, GetLocation ($1), "User-defined operators cannot return void");
2219                 $$ = new TypeExpression (compiler.BuiltinTypes.Void, GetLocation ($1));
2220           }
2221         ;
2222
2223 operator_declarator
2224         : operator_type OPERATOR overloadable_operator OPEN_PARENS
2225           {
2226                 valid_param_mod = ParameterModifierType.DefaultValue;
2227                 if ((Operator.OpType) $3 == Operator.OpType.Is)
2228                         valid_param_mod |= ParameterModifierType.Out;
2229           }
2230           opt_formal_parameter_list CLOSE_PARENS
2231           {
2232                 valid_param_mod = 0;
2233
2234                 Location loc = GetLocation ($2);
2235                 Operator.OpType op = (Operator.OpType) $3;
2236                 current_local_parameters = (ParametersCompiled)$6;
2237
2238                 int p_count = current_local_parameters.Count;
2239                 if (p_count == 1) {
2240                         if (op == Operator.OpType.Addition)
2241                                 op = Operator.OpType.UnaryPlus;
2242                         else if (op == Operator.OpType.Subtraction)
2243                                 op = Operator.OpType.UnaryNegation;
2244                 }
2245
2246                 if (IsUnaryOperator (op)) {
2247                         if (p_count == 2) {
2248                                 report.Error (1020, loc, "Overloadable binary operator expected");
2249                         } else if (p_count != 1) {
2250                                 report.Error (1535, loc, "Overloaded unary operator `{0}' takes one parameter",
2251                                         Operator.GetName (op));
2252                         }
2253                 } else if (op == Operator.OpType.Is) {
2254                         // TODO: Special checks for is operator
2255                 } else {
2256                         if (p_count == 1) {
2257                                 report.Error (1019, loc, "Overloadable unary operator expected");
2258                         } else if (p_count != 2) {
2259                                 report.Error (1534, loc, "Overloaded binary operator `{0}' takes two parameters",
2260                                         Operator.GetName (op));
2261                         }
2262                 }
2263
2264                 if (doc_support) {
2265                         tmpComment = Lexer.consume_doc_comment ();
2266                         Lexer.doc_state = XmlCommentState.NotAllowed;
2267                 }
2268
2269                 $$ = new OperatorDeclaration (op, (FullNamedExpression) $1, loc);
2270                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($3), GetLocation ($4), GetLocation ($7));
2271           }
2272         | conversion_operator_declarator
2273         ;
2274
2275 overloadable_operator
2276 // Unary operators:
2277         : BANG   { $$ = Operator.OpType.LogicalNot; }
2278         | TILDE  { $$ = Operator.OpType.OnesComplement; }
2279         | OP_INC { $$ = Operator.OpType.Increment; }
2280         | OP_DEC { $$ = Operator.OpType.Decrement; }
2281         | TRUE   { $$ = Operator.OpType.True; }
2282         | FALSE  { $$ = Operator.OpType.False; }
2283 // Unary and binary:
2284         | PLUS { $$ = Operator.OpType.Addition; }
2285         | MINUS { $$ = Operator.OpType.Subtraction; }
2286 // Binary:
2287         | STAR { $$ = Operator.OpType.Multiply; }
2288         | DIV {  $$ = Operator.OpType.Division; }
2289         | PERCENT { $$ = Operator.OpType.Modulus; }
2290         | BITWISE_AND { $$ = Operator.OpType.BitwiseAnd; }
2291         | BITWISE_OR { $$ = Operator.OpType.BitwiseOr; }
2292         | CARRET { $$ = Operator.OpType.ExclusiveOr; }
2293         | OP_SHIFT_LEFT { $$ = Operator.OpType.LeftShift; }
2294         | OP_SHIFT_RIGHT { $$ = Operator.OpType.RightShift; }
2295         | OP_EQ { $$ = Operator.OpType.Equality; }
2296         | OP_NE { $$ = Operator.OpType.Inequality; }
2297         | OP_GT { $$ = Operator.OpType.GreaterThan; }
2298         | OP_LT { $$ = Operator.OpType.LessThan; }
2299         | OP_GE { $$ = Operator.OpType.GreaterThanOrEqual; }
2300         | OP_LE { $$ = Operator.OpType.LessThanOrEqual; }
2301         | IS
2302           {
2303                 if (lang_version != LanguageVersion.Experimental)
2304                         FeatureIsNotAvailable (GetLocation ($1), "is user operator");
2305
2306                 $$ = Operator.OpType.Is;
2307           }
2308         ;
2309
2310 conversion_operator_declarator
2311         : IMPLICIT OPERATOR type OPEN_PARENS
2312           {
2313                 valid_param_mod = ParameterModifierType.DefaultValue;
2314           }
2315           opt_formal_parameter_list CLOSE_PARENS
2316           {
2317                 valid_param_mod = 0;
2318
2319                 Location loc = GetLocation ($2);
2320                 current_local_parameters = (ParametersCompiled)$6;
2321
2322                 if (current_local_parameters.Count != 1) {
2323                         report.Error (1535, loc, "Overloaded unary operator `implicit' takes one parameter");
2324                 }
2325
2326                 if (doc_support) {
2327                         tmpComment = Lexer.consume_doc_comment ();
2328                         Lexer.doc_state = XmlCommentState.NotAllowed;
2329                 }
2330
2331                 $$ = new OperatorDeclaration (Operator.OpType.Implicit, (FullNamedExpression) $3, loc);
2332                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($2), GetLocation ($4), GetLocation ($7));
2333           }
2334         | EXPLICIT OPERATOR type OPEN_PARENS
2335           {
2336                 valid_param_mod = ParameterModifierType.DefaultValue;
2337           }
2338           opt_formal_parameter_list CLOSE_PARENS
2339           {
2340                 valid_param_mod = 0;
2341
2342                 Location loc = GetLocation ($2);
2343                 current_local_parameters = (ParametersCompiled)$6;
2344
2345                 if (current_local_parameters.Count != 1) {
2346                         report.Error (1535, loc, "Overloaded unary operator `explicit' takes one parameter");
2347                 }
2348
2349                 if (doc_support) {
2350                         tmpComment = Lexer.consume_doc_comment ();
2351                         Lexer.doc_state = XmlCommentState.NotAllowed;
2352                 }
2353
2354                 $$ = new OperatorDeclaration (Operator.OpType.Explicit, (FullNamedExpression) $3, loc);
2355                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($2), GetLocation ($4), GetLocation ($7));
2356           }
2357         | IMPLICIT error
2358           {
2359                 Error_SyntaxError (yyToken);
2360                 current_local_parameters = ParametersCompiled.EmptyReadOnlyParameters;
2361                 $$ = new OperatorDeclaration (Operator.OpType.Implicit, null, GetLocation ($1));
2362           }
2363         | EXPLICIT error
2364           {
2365                 Error_SyntaxError (yyToken);
2366                 current_local_parameters = ParametersCompiled.EmptyReadOnlyParameters;
2367                 $$ = new OperatorDeclaration (Operator.OpType.Explicit, null, GetLocation ($1));
2368           }
2369         ;
2370
2371 constructor_declaration
2372         : constructor_declarator
2373           constructor_body
2374           {
2375                 Constructor c = (Constructor) $1;
2376                 c.Block = (ToplevelBlock) $2;
2377
2378                 if (doc_support)
2379                         c.DocComment = ConsumeStoredComment ();
2380
2381                 current_local_parameters = null;
2382                 if (doc_support)
2383                         Lexer.doc_state = XmlCommentState.Allowed;
2384           }
2385         ;
2386
2387 constructor_declarator
2388         : opt_attributes
2389           opt_modifiers
2390           IDENTIFIER
2391           {
2392                 if (doc_support) {
2393                         tmpComment = Lexer.consume_doc_comment ();
2394                         Lexer.doc_state = XmlCommentState.Allowed;
2395                 }
2396
2397                 valid_param_mod = ParameterModifierType.All;
2398           }
2399           OPEN_PARENS opt_formal_parameter_list CLOSE_PARENS
2400           {
2401                 valid_param_mod = 0;
2402                 current_local_parameters = (ParametersCompiled) $6;
2403
2404                 var lt = (LocatedToken) $3;
2405                 var mods = (Modifiers) $2;
2406                 var c = new Constructor (current_type, lt.Value, mods, (Attributes) $1, current_local_parameters, lt.Location);
2407
2408                 if (lt.Value != current_container.MemberName.Name) {
2409                         report.Error (1520, c.Location, "Class, struct, or interface method must have a return type");
2410                 } else if ((mods & Modifiers.STATIC) != 0) {
2411                         if (!current_local_parameters.IsEmpty) {
2412                                 report.Error (132, c.Location, "`{0}': The static constructor must be parameterless",
2413                                         c.GetSignatureForError ());
2414                         }
2415
2416                         if ((mods & Modifiers.AccessibilityMask) != 0){
2417                                 report.Error (515, c.Location,
2418                                         "`{0}': static constructor cannot have an access modifier",
2419                                         c.GetSignatureForError ());
2420                         }
2421                 } else {
2422                         if (current_type.Kind == MemberKind.Struct && current_local_parameters.IsEmpty) {
2423                                 report.Error (568, c.Location, "Structs cannot contain explicit parameterless constructors");
2424                         }
2425                 }
2426
2427                 current_type.AddConstructor (c);
2428                 lbag.AddMember (c, mod_locations, GetLocation ($5), GetLocation ($7));
2429                 $$ = c;
2430
2431                 //
2432                 // start block here, so possible anonymous methods inside
2433                 // constructor initializer can get correct parent block
2434                 //
2435                 start_block (lexer.Location);
2436           }
2437           opt_constructor_initializer
2438           {
2439                 if ($9 != null) {
2440                         var c = (Constructor) $8;
2441                         c.Initializer = (ConstructorInitializer) $9;
2442
2443                         if (c.IsStatic) {
2444                                 report.Error (514, c.Location,
2445                                         "`{0}': static constructor cannot have an explicit `this' or `base' constructor call",
2446                                         c.GetSignatureForError ());
2447                         }
2448                 }
2449
2450                 $$ = $8;
2451           }
2452         ;
2453
2454 constructor_body
2455         : block_prepared
2456         | SEMICOLON             { current_block = null; $$ = null; }
2457         ;
2458
2459 opt_constructor_initializer
2460         : /* Empty */
2461         | constructor_initializer
2462         ;
2463
2464 constructor_initializer
2465         : COLON BASE OPEN_PARENS
2466           {
2467                 ++lexer.parsing_block;
2468           }
2469           opt_argument_list CLOSE_PARENS
2470           {
2471                 --lexer.parsing_block;
2472                 $$ = new ConstructorBaseInitializer ((Arguments) $5, GetLocation ($2));
2473                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($3), GetLocation ($6));
2474           }
2475         | COLON THIS OPEN_PARENS
2476           {
2477                 ++lexer.parsing_block;
2478           }
2479           opt_argument_list CLOSE_PARENS
2480           {
2481                 --lexer.parsing_block;
2482                 $$ = new ConstructorThisInitializer ((Arguments) $5, GetLocation ($2));
2483                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($3), GetLocation ($6));
2484           }
2485         | COLON error
2486           {
2487                 Error_SyntaxError (yyToken);
2488                 $$ = new ConstructorThisInitializer (null, GetLocation ($2));
2489                 lbag.AddLocation ($$, GetLocation ($1));
2490           }
2491         | error
2492           {
2493                 Error_SyntaxError (yyToken);
2494                 $$ = null;
2495           }
2496         ;
2497
2498 destructor_declaration
2499         : opt_attributes opt_modifiers TILDE
2500           {
2501                 if (doc_support) {
2502                         tmpComment = Lexer.consume_doc_comment ();
2503                         Lexer.doc_state = XmlCommentState.NotAllowed;
2504                 }
2505
2506                 current_local_parameters = ParametersCompiled.EmptyReadOnlyParameters;
2507           }
2508           IDENTIFIER OPEN_PARENS CLOSE_PARENS method_body
2509           {
2510                 var lt = (LocatedToken) $5;
2511                 if (lt.Value != current_container.MemberName.Name){
2512                         report.Error (574, lt.Location, "Name of destructor must match name of class");
2513                 } else if (current_container.Kind != MemberKind.Class){
2514                         report.Error (575, lt.Location, "Only class types can contain destructor");
2515                 }
2516
2517                 Destructor d = new Destructor (current_type, (Modifiers) $2,
2518                         ParametersCompiled.EmptyReadOnlyParameters, (Attributes) $1, lt.Location);
2519                 if (doc_support)
2520                         d.DocComment = ConsumeStoredComment ();
2521
2522                 d.Block = (ToplevelBlock) $8;
2523                 current_type.AddMember (d);
2524                 lbag.AddMember (d, mod_locations, GetLocation ($3), GetLocation ($6), GetLocation ($7));
2525
2526                 current_local_parameters = null;
2527           }
2528         ;
2529
2530 event_declaration
2531         : opt_attributes
2532           opt_modifiers
2533           EVENT type member_declaration_name
2534           {
2535                 current_event_field = new EventField (current_type, (FullNamedExpression) $4, (Modifiers) $2, (MemberName) $5, (Attributes) $1);
2536                 current_type.AddMember (current_event_field);
2537
2538                 if (current_event_field.MemberName.ExplicitInterface != null) {
2539                         report.Error (71, current_event_field.Location, "`{0}': An explicit interface implementation of an event must use property syntax",
2540                         current_event_field.GetSignatureForError ());
2541                 }
2542
2543                 $$ = current_event_field;
2544           }
2545           opt_event_initializer
2546           opt_event_declarators
2547           SEMICOLON
2548           {
2549                 if (doc_support) {
2550                         current_event_field.DocComment = Lexer.consume_doc_comment ();
2551                         Lexer.doc_state = XmlCommentState.Allowed;
2552                 }
2553
2554                 lbag.AddMember (current_event_field, mod_locations, GetLocation ($3), GetLocation ($9));
2555                 current_event_field = null;
2556           }
2557         | opt_attributes
2558           opt_modifiers
2559           EVENT type member_declaration_name
2560           OPEN_BRACE
2561           {
2562                 current_event = new EventProperty (current_type, (FullNamedExpression) $4, (Modifiers) $2, (MemberName) $5, (Attributes) $1);
2563                 current_type.AddMember (current_event);
2564                 lbag.AddMember (current_event, mod_locations, GetLocation ($3), GetLocation ($6));
2565
2566                 lexer.EventParsing = true;
2567           }
2568           event_accessor_declarations
2569           {
2570                 if (current_container.Kind == MemberKind.Interface)
2571                         report.Error (69, GetLocation ($6), "Event in interface cannot have add or remove accessors");
2572
2573                 lexer.EventParsing = false;
2574           }
2575           CLOSE_BRACE
2576           {
2577                 if (doc_support) {
2578                         current_event.DocComment = Lexer.consume_doc_comment ();
2579                         Lexer.doc_state = XmlCommentState.Allowed;
2580                 }
2581
2582                 lbag.AppendToMember (current_event, GetLocation ($9));
2583                 current_event = null;
2584                 current_local_parameters = null;
2585           }
2586         | opt_attributes
2587           opt_modifiers
2588           EVENT type error
2589           {
2590                 Error_SyntaxError (yyToken);
2591
2592                 current_type.AddMember (new EventField (current_type, (FullNamedExpression) $4, (Modifiers) $2, MemberName.Null, (Attributes) $1));
2593           }
2594         ;
2595
2596 opt_event_initializer
2597         : /* empty */
2598         | ASSIGN
2599           {
2600                 ++lexer.parsing_block;
2601           }
2602           event_variable_initializer
2603           {
2604                 --lexer.parsing_block;
2605                 current_event_field.Initializer = (Expression) $3;
2606           }
2607         ;
2608
2609 opt_event_declarators
2610         : /* empty */
2611         | event_declarators
2612         ;
2613
2614 event_declarators
2615         : event_declarator
2616           {
2617                 current_event_field.AddDeclarator ((FieldDeclarator) $1);
2618           }
2619         | event_declarators event_declarator
2620           {
2621                 current_event_field.AddDeclarator ((FieldDeclarator) $2);
2622           }
2623         ;
2624
2625 event_declarator
2626         : COMMA IDENTIFIER
2627           {
2628                 var lt = (LocatedToken) $2;
2629                 $$ = new FieldDeclarator (new SimpleMemberName (lt.Value, lt.Location), null);
2630                 lbag.AddLocation ($$, GetLocation ($1));
2631           }
2632         | COMMA IDENTIFIER ASSIGN
2633           {
2634                 ++lexer.parsing_block;
2635           }
2636           event_variable_initializer
2637           {
2638                 --lexer.parsing_block;
2639                 var lt = (LocatedToken) $2;
2640                 $$ = new FieldDeclarator (new SimpleMemberName (lt.Value, lt.Location), (Expression) $5);
2641                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($3));
2642           }
2643         ;
2644
2645 event_variable_initializer
2646         : {
2647                 if (current_container.Kind == MemberKind.Interface) {
2648                         report.Error (68, lexer.Location, "`{0}': event in interface cannot have an initializer",
2649                                 current_event_field.GetSignatureForError ());
2650                 }
2651
2652                 if ((current_event_field.ModFlags & Modifiers.ABSTRACT) != 0) {
2653                         report.Error (74, lexer.Location, "`{0}': abstract event cannot have an initializer",
2654                                 current_event_field.GetSignatureForError ());
2655                 }
2656           }
2657           variable_initializer
2658           {
2659                 $$ = $2;
2660           }
2661         ;
2662
2663 event_accessor_declarations
2664         : add_accessor_declaration remove_accessor_declaration
2665         | remove_accessor_declaration add_accessor_declaration
2666         | add_accessor_declaration
2667           {
2668                 report.Error (65, lexer.Location, "`{0}': event property must have both add and remove accessors",
2669                         current_event.GetSignatureForError ());
2670           }
2671         | remove_accessor_declaration
2672           {
2673                 report.Error (65, lexer.Location, "`{0}': event property must have both add and remove accessors",
2674                         current_event.GetSignatureForError ());
2675           }
2676         | error
2677           {
2678                 report.Error (1055, GetLocation ($1), "An add or remove accessor expected");
2679                 $$ = null;
2680           }
2681         ;
2682
2683 add_accessor_declaration
2684         : opt_attributes opt_modifiers ADD
2685           {
2686                 if ($2 != ModifierNone) {
2687                         report.Error (1609, GetLocation ($2), "Modifiers cannot be placed on event accessor declarations");
2688                 }
2689
2690                 current_event.Add = new EventProperty.AddDelegateMethod (current_event, (Attributes) $1, GetLocation ($3));
2691                 current_local_parameters = current_event.Add.ParameterInfo;
2692
2693                 lbag.AddMember (current_event.Add, mod_locations);
2694                 lexer.EventParsing = false;
2695           }
2696           event_accessor_block
2697           {
2698                 lexer.EventParsing = true;
2699
2700                 current_event.Add.Block = (ToplevelBlock) $5;
2701
2702                 if (current_container.Kind == MemberKind.Interface) {
2703                         report.Error (531, current_event.Add.Block.StartLocation,
2704                                 "`{0}': interface members cannot have a definition", current_event.Add.GetSignatureForError ());
2705                 }
2706
2707                 current_local_parameters = null;
2708           }
2709         ;
2710
2711 remove_accessor_declaration
2712         : opt_attributes opt_modifiers REMOVE
2713           {
2714                 if ($2 != ModifierNone) {
2715                         report.Error (1609, GetLocation ($2), "Modifiers cannot be placed on event accessor declarations");
2716                 }
2717
2718                 current_event.Remove = new EventProperty.RemoveDelegateMethod (current_event, (Attributes) $1, GetLocation ($3));
2719                 current_local_parameters = current_event.Remove.ParameterInfo;
2720
2721                 lbag.AddMember (current_event.Remove, mod_locations);
2722                 lexer.EventParsing = false;
2723           }
2724           event_accessor_block
2725           {
2726                 lexer.EventParsing = true;
2727
2728                 current_event.Remove.Block = (ToplevelBlock) $5;
2729
2730                 if (current_container.Kind == MemberKind.Interface) {
2731                         report.Error (531, current_event.Remove.Block.StartLocation,
2732                                 "`{0}': interface members cannot have a definition", current_event.Remove.GetSignatureForError ());
2733                 }
2734
2735                 current_local_parameters = null;
2736           }
2737         ;
2738
2739 event_accessor_block
2740         : opt_semicolon
2741           {
2742                 report.Error (73, lexer.Location, "An add or remove accessor must have a body");
2743                 $$ = null;
2744           }
2745         | block;
2746         ;
2747
2748 attributes_without_members
2749         : attribute_sections CLOSE_BRACE
2750           {
2751                 current_type.UnattachedAttributes = (Attributes) $1;
2752                 report.Error (1519, GetLocation ($1), "An attribute is missing member declaration");
2753                 lexer.putback ('}');
2754           }
2755         ;
2756
2757 // For full ast try to recover incomplete ambiguous member
2758 // declaration in form on class X { public int }
2759 incomplete_member
2760         : opt_attributes opt_modifiers member_type CLOSE_BRACE
2761           {
2762                 report.Error (1519, lexer.Location, "Unexpected symbol `}' in class, struct, or interface member declaration");
2763
2764                 lexer.putback ('}');
2765
2766                 lexer.parsing_generic_declaration = false;
2767                 FullNamedExpression type = (FullNamedExpression) $3;
2768                 current_field = new Field (current_type, type, (Modifiers) $2, MemberName.Null, (Attributes) $1);
2769                 current_type.AddField (current_field);
2770                 $$ = current_field;
2771           }
2772         ;
2773
2774 enum_declaration
2775         : opt_attributes
2776           opt_modifiers
2777           ENUM type_declaration_name
2778           opt_enum_base
2779           {
2780                 if (doc_support)
2781                         enumTypeComment = Lexer.consume_doc_comment ();
2782           }
2783           OPEN_BRACE
2784           {
2785                 if (doc_support)
2786                         Lexer.doc_state = XmlCommentState.Allowed;
2787
2788                 MemberName name = (MemberName) $4;
2789                 if (name.IsGeneric) {
2790                         report.Error (1675, name.Location, "Enums cannot have type parameters");
2791                 }
2792
2793                 push_current_container (new Enum (current_container, (FullNamedExpression) $5, (Modifiers) $2, name, (Attributes) $1), null);
2794           }
2795           opt_enum_member_declarations
2796           {
2797                 lexer.parsing_modifiers = true;
2798
2799                 // here will be evaluated after CLOSE_BLACE is consumed.
2800                 if (doc_support)
2801                         Lexer.doc_state = XmlCommentState.Allowed;
2802           }
2803           CLOSE_BRACE opt_semicolon
2804           {
2805                 if (doc_support)
2806                         current_container.DocComment = enumTypeComment;
2807
2808                 --lexer.parsing_declaration;
2809
2810 //                      if (doc_support)
2811 //                              em.DocComment = ev.DocComment;
2812
2813                 lbag.AddMember (current_container, mod_locations, GetLocation ($3), GetLocation ($7), GetLocation ($11));
2814                 $$ = pop_current_class ();
2815           }
2816         ;
2817
2818 opt_enum_base
2819         : /* empty */
2820         | COLON type
2821          {
2822                 $$ = $2;
2823          }
2824         | COLON error
2825          {
2826                 Error_TypeExpected (GetLocation ($1));
2827                 $$ = null;
2828          }
2829         ;
2830
2831 opt_enum_member_declarations
2832         : /* empty */
2833         | enum_member_declarations
2834         | enum_member_declarations COMMA
2835           {
2836                 lbag.AddLocation ($1, GetLocation ($2));
2837           }
2838         ;
2839
2840 enum_member_declarations
2841         : enum_member_declaration
2842         | enum_member_declarations COMMA enum_member_declaration
2843           {
2844                 lbag.AddLocation ($1, GetLocation ($2));
2845                 $$ = $3;
2846           }
2847         ;
2848
2849 enum_member_declaration
2850         : opt_attributes IDENTIFIER
2851           {
2852                 var lt = (LocatedToken) $2;
2853                 var em = new EnumMember ((Enum) current_type, new MemberName (lt.Value, lt.Location), (Attributes) $1);
2854                 ((Enum) current_type).AddEnumMember (em);
2855
2856                 if (doc_support) {
2857                         em.DocComment = Lexer.consume_doc_comment ();
2858                         Lexer.doc_state = XmlCommentState.Allowed;
2859                 }
2860
2861                 $$ = em;
2862           }
2863         | opt_attributes IDENTIFIER
2864           {
2865                 ++lexer.parsing_block;
2866                 if (doc_support) {
2867                         tmpComment = Lexer.consume_doc_comment ();
2868                         Lexer.doc_state = XmlCommentState.NotAllowed;
2869                 }
2870           }
2871           ASSIGN constant_expression
2872           {
2873                 --lexer.parsing_block;
2874
2875                 var lt = (LocatedToken) $2;
2876                 var em = new EnumMember ((Enum) current_type, new MemberName (lt.Value, lt.Location), (Attributes) $1);
2877                 em.Initializer = new ConstInitializer (em, (Expression) $5, GetLocation ($4));
2878                 ((Enum) current_type).AddEnumMember (em);
2879
2880                 if (doc_support)
2881                         em.DocComment = ConsumeStoredComment ();
2882
2883                 $$ = em;
2884           }
2885         | opt_attributes IDENTIFIER error
2886           {
2887                 Error_SyntaxError (yyToken);
2888
2889                 var lt = (LocatedToken) $2;
2890                 var em = new EnumMember ((Enum) current_type, new MemberName (lt.Value, lt.Location), (Attributes) $1);
2891                 ((Enum) current_type).AddEnumMember (em);
2892
2893                 if (doc_support) {
2894                         em.DocComment = Lexer.consume_doc_comment ();
2895                         Lexer.doc_state = XmlCommentState.Allowed;
2896                 }
2897
2898                 $$ = em;
2899           }
2900         | attributes_without_members
2901         ;
2902
2903 delegate_declaration
2904         : opt_attributes
2905           opt_modifiers
2906           DELEGATE
2907           member_type type_declaration_name
2908           OPEN_PARENS
2909           {
2910                 valid_param_mod = ParameterModifierType.Ref | ParameterModifierType.Out | ParameterModifierType.Params | ParameterModifierType.DefaultValue;
2911           }
2912           opt_formal_parameter_list CLOSE_PARENS
2913           {
2914                 valid_param_mod = 0;
2915
2916                 ParametersCompiled p = (ParametersCompiled) $8;
2917
2918                 Delegate del = new Delegate (current_container, (FullNamedExpression) $4, (Modifiers) $2, (MemberName) $5, p, (Attributes) $1);
2919
2920                 p.CheckParameters (del);
2921
2922                 current_container.AddTypeContainer (del);
2923
2924                 current_delegate = del;
2925                 lexer.ConstraintsParsing = true;
2926           }
2927           opt_type_parameter_constraints_clauses
2928           {
2929                 lexer.ConstraintsParsing = false;
2930           }
2931           SEMICOLON
2932           {
2933                 if (doc_support) {
2934                         current_delegate.DocComment = Lexer.consume_doc_comment ();
2935                         Lexer.doc_state = XmlCommentState.Allowed;
2936                 }
2937
2938                 if ($11 != null)
2939                         current_delegate.SetConstraints ((List<Constraints>) $11);
2940                 lbag.AddMember (current_delegate, mod_locations, GetLocation ($3), GetLocation ($6), GetLocation ($9), GetLocation ($13));
2941
2942                 $$ = current_delegate;
2943
2944                 current_delegate = null;
2945           }
2946         ;
2947
2948 opt_nullable
2949         : /* empty */
2950         | INTERR_NULLABLE
2951           {
2952                 if (lang_version < LanguageVersion.ISO_2)
2953                         FeatureIsNotAvailable (GetLocation ($1), "nullable types");
2954
2955                 $$ = ComposedTypeSpecifier.CreateNullable (GetLocation ($1));
2956           }
2957         ;
2958
2959 namespace_or_type_expr
2960         : member_name
2961         | qualified_alias_member IDENTIFIER opt_type_argument_list
2962           {
2963                 var lt1 = (LocatedToken) $1;
2964                 var lt2 = (LocatedToken) $2;
2965
2966                 $$ = new QualifiedAliasMember (lt1.Value, lt2.Value, (TypeArguments) $3, lt1.Location);
2967                 lbag.AddLocation ($$, GetLocation ($2));
2968           }
2969         | qualified_alias_member IDENTIFIER generic_dimension
2970           {
2971                 var lt1 = (LocatedToken) $1;
2972                 var lt2 = (LocatedToken) $2;
2973
2974                 $$ = new QualifiedAliasMember (lt1.Value, lt2.Value, (int) $3, lt1.Location);
2975                 lbag.AddLocation ($$, GetLocation ($2));
2976           }
2977         ;
2978
2979 member_name
2980         : simple_name_expr
2981         | namespace_or_type_expr DOT IDENTIFIER opt_type_argument_list
2982           {
2983                 var lt = (LocatedToken) $3;
2984                 $$ = new MemberAccess ((Expression) $1, lt.Value, (TypeArguments) $4, lt.Location);
2985                 lbag.AddLocation ($$, GetLocation ($2));
2986           }
2987         | namespace_or_type_expr DOT IDENTIFIER generic_dimension
2988           {
2989                 var lt = (LocatedToken) $3;
2990                 $$ = new MemberAccess ((Expression) $1, lt.Value, (int) $4, lt.Location);
2991                 lbag.AddLocation ($$, GetLocation ($2));
2992           }
2993         ;
2994
2995 simple_name_expr
2996         : IDENTIFIER opt_type_argument_list
2997           {
2998                 var lt = (LocatedToken) $1;
2999                 $$ = new SimpleName (lt.Value, (TypeArguments)$2, lt.Location);
3000           }
3001         | IDENTIFIER generic_dimension
3002           {
3003                 var lt = (LocatedToken) $1;
3004                 $$ = new SimpleName (lt.Value, (int) $2, lt.Location);
3005           }
3006         ;
3007
3008 //
3009 // Generics arguments  (any type, without attributes)
3010 //
3011 opt_type_argument_list
3012         : /* empty */
3013         | OP_GENERICS_LT type_arguments OP_GENERICS_GT
3014           {
3015                 if (lang_version < LanguageVersion.ISO_2)
3016                         FeatureIsNotAvailable (GetLocation ($1), "generics");
3017
3018                 $$ = $2;
3019           }
3020         | OP_GENERICS_LT error
3021           {
3022                 Error_TypeExpected (lexer.Location);
3023                 $$ = new TypeArguments ();
3024           }
3025         ;
3026
3027 type_arguments
3028         : type
3029           {
3030                 TypeArguments type_args = new TypeArguments ();
3031                 type_args.Add ((FullNamedExpression) $1);
3032                 $$ = type_args;
3033           }
3034         | type_arguments COMMA type
3035           {
3036                 TypeArguments type_args = (TypeArguments) $1;
3037                 type_args.Add ((FullNamedExpression) $3);
3038                 $$ = type_args;
3039           }
3040         ;
3041
3042 //
3043 // Generics parameters (identifiers only, with attributes), used in type or method declarations
3044 //
3045 type_declaration_name
3046         : IDENTIFIER
3047           {
3048                 lexer.parsing_generic_declaration = true;
3049           }
3050           opt_type_parameter_list
3051           {
3052                 lexer.parsing_generic_declaration = false;
3053                 var lt = (LocatedToken) $1;
3054                 $$ = new MemberName (lt.Value, (TypeParameters)$3, lt.Location);
3055           }
3056         ;
3057
3058 member_declaration_name
3059         : method_declaration_name
3060           {
3061                 MemberName mn = (MemberName)$1;
3062                 if (mn.TypeParameters != null)
3063                         syntax_error (mn.Location, string.Format ("Member `{0}' cannot declare type arguments",
3064                                 mn.GetSignatureForError ()));
3065           }
3066         ;
3067
3068 method_declaration_name
3069         : type_declaration_name
3070         | explicit_interface IDENTIFIER opt_type_parameter_list
3071           {
3072                 lexer.parsing_generic_declaration = false;
3073                 var lt = (LocatedToken) $2;
3074                 $$ = new MemberName (lt.Value, (TypeParameters) $3, (ATypeNameExpression) $1, lt.Location);
3075           }
3076         ;
3077
3078 indexer_declaration_name
3079         : THIS
3080           {
3081                 lexer.parsing_generic_declaration = false;
3082                 $$ = new MemberName (TypeDefinition.DefaultIndexerName, GetLocation ($1));
3083           }
3084         | explicit_interface THIS
3085           {
3086                 lexer.parsing_generic_declaration = false;
3087                 $$ = new MemberName (TypeDefinition.DefaultIndexerName, null, (ATypeNameExpression) $1, GetLocation ($2));
3088           }
3089         ;
3090
3091 explicit_interface
3092         : IDENTIFIER opt_type_argument_list DOT
3093           {
3094                 var lt = (LocatedToken) $1;
3095                 $$ = new SimpleName (lt.Value, (TypeArguments) $2, lt.Location);
3096                 lbag.AddLocation ($$, GetLocation ($3));
3097           }
3098         | qualified_alias_member IDENTIFIER opt_type_argument_list DOT
3099           {
3100                 var lt1 = (LocatedToken) $1;
3101                 var lt2 = (LocatedToken) $2;
3102
3103                 $$ = new QualifiedAliasMember (lt1.Value, lt2.Value, (TypeArguments) $3, lt1.Location);
3104                 lbag.AddLocation ($$, GetLocation ($4));
3105           }
3106         | explicit_interface IDENTIFIER opt_type_argument_list DOT
3107           {
3108                 var lt = (LocatedToken) $2;
3109                 $$ = new MemberAccess ((ATypeNameExpression) $1, lt.Value, (TypeArguments) $3, lt.Location);
3110                 lbag.AddLocation ($$, GetLocation ($4));
3111           }
3112         ;
3113
3114 opt_type_parameter_list
3115         : /* empty */
3116         | OP_GENERICS_LT_DECL type_parameters OP_GENERICS_GT
3117           {
3118                 if (lang_version < LanguageVersion.ISO_2)
3119                         FeatureIsNotAvailable (GetLocation ($1), "generics");
3120
3121                 $$ = $2;
3122                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($3));
3123           }
3124         ;
3125
3126 type_parameters
3127         : type_parameter
3128           {
3129                 var tparams = new TypeParameters ();
3130                 tparams.Add ((TypeParameter)$1);
3131                 $$ = tparams;
3132           }
3133         | type_parameters COMMA type_parameter
3134           {
3135                 var tparams = (TypeParameters) $1;
3136                 tparams.Add ((TypeParameter)$3);
3137                 $$ = tparams;
3138                 lbag.AddLocation ($3, GetLocation ($3));
3139           }
3140         ;
3141
3142 type_parameter
3143         : opt_attributes opt_type_parameter_variance IDENTIFIER
3144           {
3145                 var lt = (LocatedToken)$3;
3146                 $$ = new TypeParameter (new MemberName (lt.Value, lt.Location), (Attributes)$1, (VarianceDecl) $2);
3147           }
3148         | error
3149           {
3150                 if (GetTokenName (yyToken) == "type")
3151                         report.Error (81, GetLocation ($1), "Type parameter declaration must be an identifier not a type");
3152                 else
3153                         Error_SyntaxError (yyToken);
3154
3155                 $$ = new TypeParameter (MemberName.Null, null, null);
3156           }
3157         ;
3158
3159 //
3160 // All types where void is allowed
3161 //
3162 type_and_void
3163         : type_expression_or_array
3164         | VOID
3165           {
3166                 $$ = new TypeExpression (compiler.BuiltinTypes.Void, GetLocation ($1));
3167           }
3168         ;
3169
3170 member_type
3171         : type_and_void
3172           {
3173                 lexer.parsing_generic_declaration = true;
3174           }
3175         ;
3176
3177 //
3178 // A type which does not allow `void' to be used
3179 //
3180 type
3181         : type_expression_or_array
3182         | void_invalid
3183         ;
3184
3185 simple_type
3186         : type_expression
3187         | void_invalid
3188         ;
3189
3190 parameter_type
3191         : type_expression_or_array
3192         | VOID
3193           {
3194                 report.Error (1536, GetLocation ($1), "Invalid parameter type `void'");
3195                 $$ = new TypeExpression (compiler.BuiltinTypes.Void, GetLocation ($1));
3196           }
3197         ;
3198
3199 type_expression_or_array
3200         : type_expression
3201         | type_expression rank_specifiers
3202           {
3203                 $$ = new ComposedCast ((FullNamedExpression) $1, (ComposedTypeSpecifier) $2);
3204           }
3205         ;
3206
3207 type_expression
3208         : namespace_or_type_expr opt_nullable
3209           {
3210                 if ($2 != null) {
3211                         $$ = new ComposedCast ((ATypeNameExpression) $1, (ComposedTypeSpecifier) $2);
3212                 } else {
3213                         var sn = $1 as SimpleName;
3214                         if (sn != null && sn.Name == "var")
3215                                 $$ = new VarExpr (sn.Location);
3216                         else
3217                                 $$ = $1;
3218                 }
3219           }
3220         | namespace_or_type_expr pointer_stars
3221           {
3222                 $$ = new ComposedCast ((ATypeNameExpression) $1, (ComposedTypeSpecifier) $2);
3223           }
3224         | builtin_type_expression
3225         ;
3226
3227 void_invalid
3228         : VOID
3229           {
3230                 Expression.Error_VoidInvalidInTheContext (GetLocation ($1), report);
3231                 $$ = new TypeExpression (compiler.BuiltinTypes.Void, GetLocation ($1));
3232           }
3233         ;
3234
3235 builtin_type_expression
3236         : builtin_types opt_nullable
3237           {
3238                 if ($2 != null)
3239                         $$ = new ComposedCast ((FullNamedExpression) $1, (ComposedTypeSpecifier) $2);
3240           }
3241         | builtin_types pointer_stars
3242           {
3243                 $$ = new ComposedCast ((FullNamedExpression) $1, (ComposedTypeSpecifier) $2);
3244           }
3245         | VOID pointer_stars
3246           {
3247                 $$ = new ComposedCast (new TypeExpression (compiler.BuiltinTypes.Void, GetLocation ($1)), (ComposedTypeSpecifier) $2);
3248           }
3249         ;
3250
3251 type_list
3252         : base_type_name
3253           {
3254                 var types = new List<FullNamedExpression> (2);
3255                 types.Add ((FullNamedExpression) $1);
3256                 $$ = types;
3257           }
3258         | type_list COMMA base_type_name
3259           {
3260                 var types = (List<FullNamedExpression>) $1;
3261                 types.Add ((FullNamedExpression) $3);
3262                 $$ = types;
3263           }
3264         ;
3265
3266 base_type_name
3267         : type
3268           {
3269                 if ($1 is ComposedCast) {
3270                         report.Error (1521, GetLocation ($1), "Invalid base type `{0}'", ((ComposedCast)$1).GetSignatureForError ());
3271                 }
3272                 $$ = $1;
3273           }
3274         ;
3275
3276 /*
3277  * replaces all the productions for isolating the various
3278  * simple types, but we need this to reuse it easily in variable_type
3279  */
3280 builtin_types
3281         : OBJECT        { $$ = new TypeExpression (compiler.BuiltinTypes.Object, GetLocation ($1)); }
3282         | STRING        { $$ = new TypeExpression (compiler.BuiltinTypes.String, GetLocation ($1)); }
3283         | BOOL          { $$ = new TypeExpression (compiler.BuiltinTypes.Bool, GetLocation ($1)); }
3284         | DECIMAL       { $$ = new TypeExpression (compiler.BuiltinTypes.Decimal, GetLocation ($1)); }
3285         | FLOAT         { $$ = new TypeExpression (compiler.BuiltinTypes.Float, GetLocation ($1)); }
3286         | DOUBLE        { $$ = new TypeExpression (compiler.BuiltinTypes.Double, GetLocation ($1)); }
3287         | integral_type
3288         ;
3289
3290 integral_type
3291         : SBYTE         { $$ = new TypeExpression (compiler.BuiltinTypes.SByte, GetLocation ($1)); }
3292         | BYTE          { $$ = new TypeExpression (compiler.BuiltinTypes.Byte, GetLocation ($1)); }
3293         | SHORT         { $$ = new TypeExpression (compiler.BuiltinTypes.Short, GetLocation ($1)); }
3294         | USHORT        { $$ = new TypeExpression (compiler.BuiltinTypes.UShort, GetLocation ($1)); }
3295         | INT           { $$ = new TypeExpression (compiler.BuiltinTypes.Int, GetLocation ($1)); }
3296         | UINT          { $$ = new TypeExpression (compiler.BuiltinTypes.UInt, GetLocation ($1)); }
3297         | LONG          { $$ = new TypeExpression (compiler.BuiltinTypes.Long, GetLocation ($1)); }
3298         | ULONG         { $$ = new TypeExpression (compiler.BuiltinTypes.ULong, GetLocation ($1)); }
3299         | CHAR          { $$ = new TypeExpression (compiler.BuiltinTypes.Char, GetLocation ($1)); }
3300         ;
3301
3302 //
3303 // Expressions, section 7.5
3304 //
3305
3306
3307 primary_expression
3308         : type_name_expression
3309         | literal
3310         | array_creation_expression
3311         | parenthesized_expression
3312         | default_value_expression
3313         | invocation_expression
3314         | element_access
3315         | this_access
3316         | base_access
3317         | post_increment_expression
3318         | post_decrement_expression
3319         | object_or_delegate_creation_expression
3320         | anonymous_type_expression
3321         | typeof_expression
3322         | sizeof_expression
3323         | checked_expression
3324         | unchecked_expression
3325         | pointer_member_access
3326         | anonymous_method_expression
3327         | undocumented_expressions
3328         | interpolated_string
3329         ;
3330
3331 type_name_expression
3332         : simple_name_expr
3333         | IDENTIFIER GENERATE_COMPLETION {
3334                 var lt = (LocatedToken) $1;
3335                $$ = new CompletionSimpleName (MemberName.MakeName (lt.Value, null), lt.Location);
3336           }
3337         | member_access
3338         ;
3339
3340 literal
3341         : boolean_literal
3342         | LITERAL
3343         | NULL                  { $$ = new NullLiteral (GetLocation ($1)); }
3344         ;
3345
3346 boolean_literal
3347         : TRUE                  { $$ = new BoolLiteral (compiler.BuiltinTypes, true, GetLocation ($1)); }
3348         | FALSE                 { $$ = new BoolLiteral (compiler.BuiltinTypes, false, GetLocation ($1)); }
3349         ;
3350
3351 interpolated_string
3352         : INTERPOLATED_STRING interpolations INTERPOLATED_STRING_END
3353           {
3354                 $$ = new InterpolatedString ((StringLiteral) $1, (List<Expression>) $2, (StringLiteral) $3);
3355           }
3356         | INTERPOLATED_STRING_END
3357           {
3358                 $$ = new InterpolatedString ((StringLiteral) $1, null, null);
3359           }
3360         ;
3361
3362 interpolations
3363         : interpolation
3364           {
3365                 var list = new List<Expression> ();
3366                 list.Add ((InterpolatedStringInsert) $1);
3367                 $$ = list;
3368           }
3369         | interpolations INTERPOLATED_STRING interpolation
3370           {
3371                 var list = (List<Expression>) $1;
3372                 list.Add ((StringLiteral) $2);
3373                 list.Add ((InterpolatedStringInsert) $3);
3374                 $$ = list;
3375           }
3376         ;
3377
3378 interpolation
3379         : expression
3380           {
3381                 $$ = new InterpolatedStringInsert ((Expression) $1);
3382           }
3383         | expression COMMA expression
3384           {
3385                 $$ = new InterpolatedStringInsert ((Expression) $1) {
3386                         Alignment = (Expression)$3
3387                 };
3388           }
3389         | expression COLON
3390           {
3391                 lexer.parsing_interpolation_format = true;
3392           }
3393           LITERAL
3394           {
3395                 lexer.parsing_interpolation_format = false;
3396
3397                 $$ = new InterpolatedStringInsert ((Expression) $1) {
3398                         Format = (string)$4
3399                 };
3400           }
3401         | expression COMMA expression COLON
3402           {
3403                 lexer.parsing_interpolation_format = true;
3404           }
3405           LITERAL
3406           {
3407                 lexer.parsing_interpolation_format = false;
3408
3409                 $$ = new InterpolatedStringInsert ((Expression) $1) {
3410                         Alignment = (Expression)$3,
3411                         Format = (string) $6
3412                 };
3413           }
3414         ;
3415
3416
3417 //
3418 // Here is the trick, tokenizer may think that parens is a special but
3419 // parser is interested in open parens only, so we merge them.
3420 // Consider: if (a)foo ();
3421 //
3422 open_parens_any
3423         : OPEN_PARENS
3424         | OPEN_PARENS_CAST
3425         ;
3426
3427 //
3428 // Use this production to accept closing parenthesis or
3429 // performing completion
3430 //
3431 close_parens
3432         : CLOSE_PARENS
3433         | COMPLETE_COMPLETION
3434         ;
3435
3436
3437 parenthesized_expression
3438         : OPEN_PARENS expression CLOSE_PARENS
3439           {
3440                 $$ = new ParenthesizedExpression ((Expression) $2, GetLocation ($1));
3441                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($3));
3442           }
3443         | OPEN_PARENS expression COMPLETE_COMPLETION
3444           {
3445                 $$ = new ParenthesizedExpression ((Expression) $2, GetLocation ($1));
3446           }
3447         ;
3448
3449 member_access
3450         : primary_expression DOT identifier_inside_body opt_type_argument_list
3451           {
3452                 var lt = (LocatedToken) $3;
3453                 $$ = new MemberAccess ((Expression) $1, lt.Value, (TypeArguments) $4, lt.Location);
3454                 lbag.AddLocation ($$, GetLocation ($2));
3455           }
3456         | primary_expression DOT identifier_inside_body generic_dimension
3457           {
3458                 var lt = (LocatedToken) $3;
3459                 $$ = new MemberAccess ((Expression) $1, lt.Value, (int) $4, lt.Location);
3460                 lbag.AddLocation ($$, GetLocation ($2));
3461           }
3462         | primary_expression INTERR_OPERATOR DOT identifier_inside_body opt_type_argument_list
3463           {
3464                 if (lang_version < LanguageVersion.V_6)
3465                         FeatureIsNotAvailable (GetLocation ($2), "null propagating operator");
3466
3467                 var lt = (LocatedToken) $4;
3468                 $$ = new ConditionalMemberAccess ((Expression) $1, lt.Value, (TypeArguments) $5, lt.Location);
3469                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($3));
3470           }
3471         | builtin_types DOT identifier_inside_body opt_type_argument_list
3472           {
3473                 var lt = (LocatedToken) $3;
3474                 $$ = new MemberAccess ((Expression) $1, lt.Value, (TypeArguments) $4, lt.Location);
3475                 lbag.AddLocation ($$, GetLocation ($2));
3476           }
3477         | BASE DOT identifier_inside_body opt_type_argument_list
3478           {
3479                 var lt = (LocatedToken) $3;
3480                 $$ = new MemberAccess (new BaseThis (GetLocation ($1)), lt.Value, (TypeArguments) $4, lt.Location);
3481                 lbag.AddLocation ($$, GetLocation ($2));
3482           }
3483         | AWAIT DOT identifier_inside_body opt_type_argument_list
3484           {
3485                 var lt = (LocatedToken) $3;
3486                 $$ = new MemberAccess (new SimpleName ("await", ((LocatedToken) $1).Location), lt.Value, (TypeArguments) $4, lt.Location);
3487                 lbag.AddLocation ($$, GetLocation ($2));
3488           }
3489         | qualified_alias_member identifier_inside_body opt_type_argument_list
3490           {
3491                 var lt1 = (LocatedToken) $1;
3492                 var lt2 = (LocatedToken) $2;
3493
3494                 $$ = new QualifiedAliasMember (lt1.Value, lt2.Value, (TypeArguments) $3, lt1.Location);
3495                 lbag.AddLocation ($$, GetLocation ($2));
3496           }
3497         | qualified_alias_member identifier_inside_body generic_dimension
3498           {
3499                 var lt1 = (LocatedToken) $1;
3500                 var lt2 = (LocatedToken) $2;
3501
3502                 $$ = new QualifiedAliasMember (lt1.Value, lt2.Value, (int) $3, lt1.Location);
3503                 lbag.AddLocation ($$, GetLocation ($2));
3504           }
3505         | primary_expression DOT GENERATE_COMPLETION {
3506                 $$ = new CompletionMemberAccess ((Expression) $1, null,GetLocation ($3));
3507           }
3508         | primary_expression DOT IDENTIFIER GENERATE_COMPLETION {
3509                 var lt = (LocatedToken) $3;
3510                 $$ = new CompletionMemberAccess ((Expression) $1, lt.Value, lt.Location);
3511           }
3512         | builtin_types DOT GENERATE_COMPLETION
3513           {
3514                 $$ = new CompletionMemberAccess ((Expression) $1, null, lexer.Location);
3515           }
3516         | builtin_types DOT IDENTIFIER GENERATE_COMPLETION {
3517                 var lt = (LocatedToken) $3;
3518                 $$ = new CompletionMemberAccess ((Expression) $1, lt.Value, lt.Location);
3519           }
3520         ;
3521
3522 invocation_expression
3523         : primary_expression open_parens_any opt_argument_list close_parens
3524           {
3525                 $$ = new Invocation ((Expression) $1, (Arguments) $3);
3526                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
3527           }
3528         | primary_expression open_parens_any argument_list error
3529           {
3530                 Error_SyntaxError (yyToken);
3531
3532                 $$ = new Invocation ((Expression) $1, (Arguments) $3);
3533                 lbag.AddLocation ($$, GetLocation ($2));
3534           }
3535         | primary_expression open_parens_any error
3536           {
3537                 Error_SyntaxError (yyToken);
3538
3539                 $$ = new Invocation ((Expression) $1, null);
3540                 lbag.AddLocation ($$, GetLocation ($2));
3541           }
3542         ;
3543
3544 opt_object_or_collection_initializer
3545         : /* empty */           { $$ = null; }
3546         | object_or_collection_initializer
3547         ;
3548
3549 object_or_collection_initializer
3550         : OPEN_BRACE opt_member_initializer_list close_brace_or_complete_completion
3551           {
3552                 if ($2 == null) {
3553                         $$ = new CollectionOrObjectInitializers (GetLocation ($1));
3554                 } else {
3555                         $$ = new CollectionOrObjectInitializers ((List<Expression>) $2, GetLocation ($1));
3556                 }
3557                 lbag.AddLocation ($$, GetLocation ($3));
3558           }
3559         | OPEN_BRACE member_initializer_list COMMA CLOSE_BRACE
3560           {
3561                 $$ = new CollectionOrObjectInitializers ((List<Expression>) $2, GetLocation ($1));
3562                 lbag.AddLocation ($$, GetLocation ($3), GetLocation ($4));
3563           }
3564         ;
3565
3566 opt_member_initializer_list
3567         : /* empty */           { $$ = null; }
3568         | member_initializer_list
3569         {
3570                 $$ = $1;
3571         }
3572         ;
3573
3574 member_initializer_list
3575         : member_initializer
3576           {
3577                 var a = new List<Expression> ();
3578                 a.Add ((Expression) $1);
3579                 $$ = a;
3580           }
3581         | member_initializer_list COMMA member_initializer
3582           {
3583                 var a = (List<Expression>)$1;
3584                 a.Add ((Expression) $3);
3585                 $$ = a;
3586           }
3587         | member_initializer_list error {
3588                 Error_SyntaxError (yyToken);
3589                 $$ = $1;
3590           }
3591         ;
3592
3593 member_initializer
3594         : IDENTIFIER ASSIGN initializer_value
3595           {
3596                 var lt = (LocatedToken) $1;
3597                 $$ = new ElementInitializer (lt.Value, (Expression)$3, lt.Location);
3598                 lbag.AddLocation ($$, GetLocation ($2));
3599           }
3600         | AWAIT ASSIGN initializer_value
3601           {
3602                 var lt = (LocatedToken) Error_AwaitAsIdentifier ($1);
3603                 $$ = new ElementInitializer (lt.Value, (Expression)$3, lt.Location);
3604                 lbag.AddLocation ($$, GetLocation ($2));
3605           }
3606         | GENERATE_COMPLETION
3607           {
3608                 $$ = new CompletionElementInitializer (null, GetLocation ($1));
3609           }
3610         | non_assignment_expression opt_COMPLETE_COMPLETION  {
3611                 CompletionSimpleName csn = $1 as CompletionSimpleName;
3612                 if (csn == null)
3613                         $$ = new CollectionElementInitializer ((Expression)$1);
3614                 else
3615                         $$ = new CompletionElementInitializer (csn.Prefix, csn.Location);
3616           }
3617         | OPEN_BRACE expression_list CLOSE_BRACE
3618           {
3619                 if ($2 == null)
3620                         $$ = new CollectionElementInitializer (GetLocation ($1));
3621                 else
3622                         $$ = new CollectionElementInitializer ((List<Expression>)$2, GetLocation ($1));
3623
3624                 lbag.AddLocation ($$, GetLocation ($3));
3625           }
3626         | OPEN_BRACKET_EXPR argument_list CLOSE_BRACKET ASSIGN initializer_value
3627           {
3628                 if (lang_version < LanguageVersion.V_6)
3629                         FeatureIsNotAvailable (GetLocation ($1), "dictionary initializer");
3630
3631                 $$ = new DictionaryElementInitializer ((Arguments)$2, (Expression) $5, GetLocation ($1));
3632                 lbag.AddLocation ($$, GetLocation ($3), GetLocation ($4));
3633           }
3634         | OPEN_BRACE CLOSE_BRACE
3635           {
3636                 report.Error (1920, GetLocation ($1), "An element initializer cannot be empty");
3637                 $$ = new CollectionElementInitializer (GetLocation ($1));
3638                 lbag.AddLocation ($$, GetLocation ($2));
3639           }
3640         ;
3641
3642 initializer_value
3643         : expression
3644         | object_or_collection_initializer
3645         ;
3646
3647 opt_argument_list
3648         : /* empty */           { $$ = null; }
3649         | argument_list
3650         ;
3651
3652 argument_list
3653         : argument_or_named_argument
3654           {
3655                 Arguments list = new Arguments (4);
3656                 list.Add ((Argument) $1);
3657                 $$ = list;
3658           }
3659         | argument_list COMMA argument
3660           {
3661                 Arguments list = (Arguments) $1;
3662                 if (list [list.Count - 1] is NamedArgument)
3663                         Error_NamedArgumentExpected ((NamedArgument) list [list.Count - 1]);
3664
3665                 list.Add ((Argument) $3);
3666                 $$ = list;
3667           }
3668         | argument_list COMMA named_argument
3669           {
3670                 Arguments list = (Arguments) $1;
3671                 NamedArgument a = (NamedArgument) $3;
3672                 for (int i = 0; i < list.Count; ++i) {
3673                         NamedArgument na = list [i] as NamedArgument;
3674                         if (na != null && na.Name == a.Name)
3675                                 report.Error (1740, na.Location, "Named argument `{0}' specified multiple times",
3676                                         na.Name);
3677                 }
3678
3679                 list.Add (a);
3680                 $$ = list;
3681           }
3682         | argument_list COMMA error
3683           {
3684                 if (lexer.putback_char == -1)
3685                         lexer.putback (')'); // TODO: Wrong but what can I do
3686                 Error_SyntaxError (yyToken);
3687                 $$ = $1;
3688           }
3689         | COMMA error
3690           {
3691                 report.Error (839, GetLocation ($1), "An argument is missing");
3692                 $$ = null;
3693           }
3694         ;
3695
3696 argument
3697         : expression
3698           {
3699                 $$ = new Argument ((Expression) $1);
3700           }
3701         | non_simple_argument
3702         ;
3703
3704 argument_or_named_argument
3705         : argument
3706         | named_argument
3707         ;
3708
3709 non_simple_argument
3710         : REF variable_reference
3711           {
3712                 $$ = new Argument ((Expression) $2, Argument.AType.Ref);
3713                 lbag.AddLocation ($$, GetLocation ($1));
3714           }
3715         | REF declaration_expression
3716           {
3717                 $$ = new Argument ((Expression) $2, Argument.AType.Ref);
3718           }
3719         | OUT variable_reference
3720           {
3721                 $$ = new Argument ((Expression) $2, Argument.AType.Out);
3722                 lbag.AddLocation ($$, GetLocation ($1));
3723           }
3724         | OUT declaration_expression
3725           {
3726                 $$ = new Argument ((Expression) $2, Argument.AType.Out);
3727           }
3728         | ARGLIST OPEN_PARENS argument_list CLOSE_PARENS
3729           {
3730                 $$ = new Argument (new Arglist ((Arguments) $3, GetLocation ($1)));
3731                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
3732           }
3733         | ARGLIST OPEN_PARENS CLOSE_PARENS
3734           {
3735                 $$ = new Argument (new Arglist (GetLocation ($1)));
3736                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($3));
3737           }
3738         ;
3739
3740 declaration_expression
3741         : OPEN_PARENS declaration_expression CLOSE_PARENS
3742           {
3743                 $$ = new ParenthesizedExpression ((Expression) $2, GetLocation ($1));
3744                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($3));
3745           }
3746 /*
3747         | CHECKED open_parens_any declaration_expression CLOSE_PARENS
3748           {
3749                 $$ = new CheckedExpr ((Expression) $3, GetLocation ($1));
3750                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
3751           }
3752         | UNCHECKED open_parens_any declaration_expression CLOSE_PARENS
3753           {
3754                 $$ = new UnCheckedExpr ((Expression) $3, GetLocation ($1));
3755                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
3756           }
3757 */
3758         | variable_type identifier_inside_body
3759           {
3760                 if (lang_version != LanguageVersion.Experimental)
3761                         FeatureIsNotAvailable (GetLocation ($1), "declaration expression");
3762
3763                 var lt = (LocatedToken) $2;
3764                 var lv = new LocalVariable (current_block, lt.Value, lt.Location);
3765                 current_block.AddLocalName (lv);
3766                 $$ = new DeclarationExpression ((FullNamedExpression) $1, lv);
3767           }
3768         | variable_type identifier_inside_body ASSIGN expression
3769           {
3770                 if (lang_version != LanguageVersion.Experimental)
3771                         FeatureIsNotAvailable (GetLocation ($1), "declaration expression");
3772
3773                 var lt = (LocatedToken) $2;
3774                 var lv = new LocalVariable (current_block, lt.Value, lt.Location);
3775                 current_block.AddLocalName (lv);
3776                 $$ = new DeclarationExpression ((FullNamedExpression) $1, lv) {
3777                         Initializer = (Expression) $4
3778                 };
3779           }
3780         ;
3781
3782 variable_reference
3783         : expression
3784         ;
3785
3786 element_access
3787         : primary_expression OPEN_BRACKET_EXPR expression_list_arguments CLOSE_BRACKET
3788           {
3789                 $$ = new ElementAccess ((Expression) $1, (Arguments) $3, GetLocation ($2));
3790                 lbag.AddLocation ($$, GetLocation ($4));
3791           }
3792         | primary_expression INTERR_OPERATOR OPEN_BRACKET_EXPR expression_list_arguments CLOSE_BRACKET
3793           {
3794                 if (lang_version < LanguageVersion.V_6)
3795                         FeatureIsNotAvailable (GetLocation ($2), "null propagating operator");
3796
3797                 $$ = new ElementAccess ((Expression) $1, (Arguments) $4, GetLocation ($3)) {
3798                         ConditionalAccess = true
3799                 };
3800
3801                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($5));
3802           }
3803         | primary_expression OPEN_BRACKET_EXPR expression_list_arguments error
3804           {
3805                 Error_SyntaxError (yyToken);
3806                 $$ = new ElementAccess ((Expression) $1, (Arguments) $3, GetLocation ($2));
3807           }
3808         | primary_expression OPEN_BRACKET_EXPR error
3809           {
3810                 Error_SyntaxError (yyToken);
3811                 $$ = new ElementAccess ((Expression) $1, null, GetLocation ($2));
3812           }
3813         ;
3814
3815 expression_list
3816         : expression_or_error
3817           {
3818                 var list = new List<Expression> (4);
3819                 list.Add ((Expression) $1);
3820                 $$ = list;
3821           }
3822         | expression_list COMMA expression_or_error
3823           {
3824                 var list = (List<Expression>) $1;
3825                 list.Add ((Expression) $3);
3826                 $$ = list;
3827           }
3828         ;
3829
3830 expression_list_arguments
3831         : expression_list_argument
3832           {
3833                 Arguments args = new Arguments (4);
3834                 args.Add ((Argument) $1);
3835                 $$ = args;
3836           }
3837         | expression_list_arguments COMMA expression_list_argument
3838           {
3839                 Arguments args = (Arguments) $1;
3840                 if (args [args.Count - 1] is NamedArgument && !($3 is NamedArgument))
3841                         Error_NamedArgumentExpected ((NamedArgument) args [args.Count - 1]);
3842
3843                 args.Add ((Argument) $3);
3844                 $$ = args;
3845           }
3846         ;
3847
3848 expression_list_argument
3849         : expression
3850           {
3851                 $$ = new Argument ((Expression) $1);
3852           }
3853         | named_argument
3854         ;
3855
3856 this_access
3857         : THIS
3858           {
3859                 $$ = new This (GetLocation ($1));
3860           }
3861         ;
3862
3863 base_access
3864         : BASE OPEN_BRACKET_EXPR expression_list_arguments CLOSE_BRACKET
3865           {
3866                 $$ = new ElementAccess (new BaseThis (GetLocation ($1)), (Arguments) $3, GetLocation ($2));
3867                 lbag.AddLocation ($$, GetLocation ($4));
3868           }
3869         | BASE OPEN_BRACKET error
3870           {
3871                 Error_SyntaxError (yyToken);
3872                 $$ = new ElementAccess (null, null, GetLocation ($2));
3873           }
3874         ;
3875
3876 post_increment_expression
3877         : primary_expression OP_INC
3878           {
3879                 $$ = new UnaryMutator (UnaryMutator.Mode.PostIncrement, (Expression) $1, GetLocation ($2));
3880           }
3881         ;
3882
3883 post_decrement_expression
3884         : primary_expression OP_DEC
3885           {
3886                 $$ = new UnaryMutator (UnaryMutator.Mode.PostDecrement, (Expression) $1, GetLocation ($2));
3887           }
3888         ;
3889
3890 object_or_delegate_creation_expression
3891         : NEW new_expr_type open_parens_any opt_argument_list CLOSE_PARENS opt_object_or_collection_initializer
3892           {
3893                 if ($6 != null) {
3894                         if (lang_version <= LanguageVersion.ISO_2)
3895                                 FeatureIsNotAvailable (GetLocation ($1), "object initializers");
3896
3897                         $$ = new NewInitialize ((FullNamedExpression) $2, (Arguments) $4, (CollectionOrObjectInitializers) $6, GetLocation ($1));
3898                 } else {
3899                         $$ = new New ((FullNamedExpression) $2, (Arguments) $4, GetLocation ($1));
3900                 }
3901
3902                 lbag.AddLocation ($$, GetLocation ($3), GetLocation ($5));
3903           }
3904         | NEW new_expr_type object_or_collection_initializer
3905           {
3906                 if (lang_version <= LanguageVersion.ISO_2)
3907                         FeatureIsNotAvailable (GetLocation ($1), "collection initializers");
3908
3909                 $$ = new NewInitialize ((FullNamedExpression) $2, null, (CollectionOrObjectInitializers) $3, GetLocation ($1));
3910           }
3911         ;
3912
3913 array_creation_expression
3914         : NEW new_expr_type OPEN_BRACKET_EXPR expression_list CLOSE_BRACKET
3915           opt_rank_specifier
3916           opt_array_initializer
3917           {
3918                 $$ = new ArrayCreation ((FullNamedExpression) $2, (List<Expression>) $4,
3919                                 new ComposedTypeSpecifier (((List<Expression>) $4).Count, GetLocation ($3)) {
3920                                         Next = (ComposedTypeSpecifier) $6
3921                                 }, (ArrayInitializer) $7, GetLocation ($1));
3922                 lbag.AddLocation ($$, GetLocation ($3), GetLocation ($5));
3923           }
3924         | NEW new_expr_type rank_specifiers opt_array_initializer
3925           {
3926                 if ($4 == null)
3927                         report.Error (1586, GetLocation ($1), "Array creation must have array size or array initializer");
3928
3929                 $$ = new ArrayCreation ((FullNamedExpression) $2, (ComposedTypeSpecifier) $3, (ArrayInitializer) $4, GetLocation ($1)) {
3930                         NoEmptyInterpolation = true
3931                 };
3932           }
3933         | NEW rank_specifier array_initializer
3934           {
3935                 if (lang_version <= LanguageVersion.ISO_2)
3936                         FeatureIsNotAvailable (GetLocation ($1), "implicitly typed arrays");
3937
3938                 $$ = new ImplicitlyTypedArrayCreation ((ComposedTypeSpecifier) $2, (ArrayInitializer) $3, GetLocation ($1));
3939           }
3940         | NEW new_expr_type OPEN_BRACKET CLOSE_BRACKET OPEN_BRACKET_EXPR error CLOSE_BRACKET
3941           {
3942                 report.Error (178, GetLocation ($6), "Invalid rank specifier, expecting `,' or `]'");
3943                 $$ = new ArrayCreation ((FullNamedExpression) $2, null, GetLocation ($1));
3944           }
3945         | NEW new_expr_type error
3946           {
3947                 Error_SyntaxError (yyToken);
3948                 // It can be any of new expression, create the most common one
3949                 $$ = new New ((FullNamedExpression) $2, null, GetLocation ($1));
3950           }
3951         ;
3952
3953 new_expr_type
3954         : {
3955                 ++lexer.parsing_type;
3956           }
3957           simple_type
3958           {
3959                 --lexer.parsing_type;
3960                 $$ = $2;
3961           }
3962         ;
3963
3964 anonymous_type_expression
3965         : NEW OPEN_BRACE anonymous_type_parameters_opt_comma CLOSE_BRACE
3966           {
3967                 if (lang_version <= LanguageVersion.ISO_2)
3968                         FeatureIsNotAvailable (GetLocation ($1), "anonymous types");
3969
3970                 $$ = new NewAnonymousType ((List<AnonymousTypeParameter>) $3, current_container, GetLocation ($1));
3971
3972                 // TODO: lbag comma location
3973                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
3974           }
3975         | NEW OPEN_BRACE GENERATE_COMPLETION
3976           {
3977                 $$ = new EmptyCompletion ();
3978           }
3979         ;
3980
3981 anonymous_type_parameters_opt_comma
3982         : anonymous_type_parameters_opt
3983         | anonymous_type_parameters COMMA
3984         ;
3985
3986 anonymous_type_parameters_opt
3987         : { $$ = null; }
3988         | anonymous_type_parameters
3989         ;
3990
3991 anonymous_type_parameters
3992         : anonymous_type_parameter
3993           {
3994                 var a = new List<AnonymousTypeParameter> (4);
3995                 a.Add ((AnonymousTypeParameter) $1);
3996                 $$ = a;
3997           }
3998         | anonymous_type_parameters COMMA anonymous_type_parameter
3999           {
4000                 var a = (List<AnonymousTypeParameter>) $1;
4001                 a.Add ((AnonymousTypeParameter) $3);
4002                 $$ = a;
4003           }
4004         | COMPLETE_COMPLETION
4005           {
4006                 $$ = new EmptyCompletion ();
4007           }
4008         | anonymous_type_parameter COMPLETE_COMPLETION
4009           {
4010                 $$ = $1;
4011           }
4012         ;
4013
4014 anonymous_type_parameter
4015         : identifier_inside_body ASSIGN variable_initializer
4016           {
4017                 var lt = (LocatedToken)$1;
4018                 $$ = new AnonymousTypeParameter ((Expression)$3, lt.Value, lt.Location);
4019                 lbag.AddLocation ($$, GetLocation ($2));
4020           }
4021         | identifier_inside_body
4022           {
4023                 var lt = (LocatedToken)$1;
4024                 $$ = new AnonymousTypeParameter (new SimpleName (lt.Value, lt.Location),
4025                         lt.Value, lt.Location);
4026           }
4027         | member_access
4028           {
4029                 MemberAccess ma = (MemberAccess) $1;
4030                 $$ = new AnonymousTypeParameter (ma, ma.Name, ma.Location);
4031           }
4032         | error
4033           {
4034                 report.Error (746, lexer.Location,
4035                         "Invalid anonymous type member declarator. Anonymous type members must be a member assignment, simple name or member access expression");
4036                 $$ = null;
4037           }
4038         ;
4039
4040 opt_rank_specifier
4041         : /* empty */
4042         | rank_specifiers
4043         ;
4044
4045 rank_specifiers
4046         : rank_specifier
4047         | rank_specifier rank_specifiers
4048           {
4049                 ((ComposedTypeSpecifier) $1).Next = (ComposedTypeSpecifier) $2;
4050                 $$ = $1;
4051           }
4052         ;
4053
4054 rank_specifier
4055         : OPEN_BRACKET CLOSE_BRACKET
4056           {
4057                 $$ = ComposedTypeSpecifier.CreateArrayDimension (1, GetLocation ($1));
4058                 lbag.AddLocation ($$, GetLocation ($2));
4059           }
4060         | OPEN_BRACKET dim_separators CLOSE_BRACKET
4061           {
4062                 $$ = ComposedTypeSpecifier.CreateArrayDimension ((int)$2, GetLocation ($1));
4063                 lbag.AddLocation ($$, GetLocation ($3));
4064           }
4065         ;
4066
4067 dim_separators
4068         : COMMA
4069           {
4070                 $$ = 2;
4071           }
4072         | dim_separators COMMA
4073           {
4074                 $$ = ((int) $1) + 1;
4075           }
4076         ;
4077
4078 opt_array_initializer
4079         : /* empty */
4080           {
4081                 $$ = null;
4082           }
4083         | array_initializer
4084           {
4085                 $$ = $1;
4086           }
4087         ;
4088
4089 array_initializer
4090         : OPEN_BRACE CLOSE_BRACE
4091           {
4092                 var ai = new ArrayInitializer (0, GetLocation ($1));
4093                 ai.VariableDeclaration = current_variable;
4094                 lbag.AddLocation (ai, GetLocation ($2));
4095                 $$ = ai;
4096           }
4097         | OPEN_BRACE variable_initializer_list opt_comma CLOSE_BRACE
4098           {
4099                 var ai = new ArrayInitializer ((List<Expression>) $2, GetLocation ($1));
4100                 ai.VariableDeclaration = current_variable;
4101                 if ($3 != null) {
4102                         lbag.AddLocation (ai, GetLocation ($3), GetLocation ($4));
4103                 } else {
4104                         lbag.AddLocation (ai, GetLocation ($4));
4105                 }
4106                 $$ = ai;
4107           }
4108         ;
4109
4110 variable_initializer_list
4111         : variable_initializer
4112           {
4113                 var list = new List<Expression> (4);
4114                 list.Add ((Expression) $1);
4115                 $$ = list;
4116           }
4117         | variable_initializer_list COMMA variable_initializer
4118           {
4119                 var list = (List<Expression>) $1;
4120                 list.Add ((Expression) $3);
4121                 $$ = list;
4122           }
4123         ;
4124
4125 typeof_expression
4126         : TYPEOF open_parens_any typeof_type_expression CLOSE_PARENS
4127           {
4128                 $$ = new TypeOf ((FullNamedExpression) $3, GetLocation ($1));
4129                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
4130           }
4131         ;
4132
4133 typeof_type_expression
4134         : type_and_void
4135         | error
4136          {
4137                 Error_TypeExpected (lexer.Location);
4138                 $$ = null;
4139          }
4140         ;
4141
4142 generic_dimension
4143         : GENERIC_DIMENSION
4144           {
4145                 if (lang_version < LanguageVersion.ISO_2)
4146                         FeatureIsNotAvailable (GetLocation ($1), "generics");
4147
4148                 $$ = $1;
4149           }
4150         ;
4151
4152 qualified_alias_member
4153         : IDENTIFIER DOUBLE_COLON
4154           {
4155                 var lt = (LocatedToken) $1;
4156                 if (lang_version == LanguageVersion.ISO_1)
4157                         FeatureIsNotAvailable (lt.Location, "namespace alias qualifier");
4158
4159                 $$ = lt;
4160           }
4161         ;
4162
4163 sizeof_expression
4164         : SIZEOF open_parens_any type CLOSE_PARENS
4165           {
4166                 $$ = new SizeOf ((Expression) $3, GetLocation ($1));
4167                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
4168           }
4169         | SIZEOF open_parens_any type error
4170           {
4171                 Error_SyntaxError (yyToken);
4172
4173                 $$ = new SizeOf ((Expression) $3, GetLocation ($1));
4174                 lbag.AddLocation ($$, GetLocation ($2));
4175           }
4176         ;
4177
4178 checked_expression
4179         : CHECKED open_parens_any expression CLOSE_PARENS
4180           {
4181                 $$ = new CheckedExpr ((Expression) $3, GetLocation ($1));
4182                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
4183           }
4184         | CHECKED error
4185           {
4186                 Error_SyntaxError (yyToken);
4187
4188                 $$ = new CheckedExpr (null, GetLocation ($1));
4189           }
4190         ;
4191
4192 unchecked_expression
4193         : UNCHECKED open_parens_any expression CLOSE_PARENS
4194           {
4195                 $$ = new UnCheckedExpr ((Expression) $3, GetLocation ($1));
4196                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
4197           }
4198         | UNCHECKED error
4199           {
4200                 Error_SyntaxError (yyToken);
4201
4202                 $$ = new UnCheckedExpr (null, GetLocation ($1));
4203           }
4204         ;
4205
4206 pointer_member_access
4207         : primary_expression OP_PTR IDENTIFIER opt_type_argument_list
4208           {
4209                 var lt = (LocatedToken) $3;
4210                 $$ = new MemberAccess (new Indirection ((Expression) $1, GetLocation ($2)), lt.Value, (TypeArguments) $4, lt.Location);
4211           }
4212         ;
4213
4214 anonymous_method_expression
4215         : DELEGATE opt_anonymous_method_signature
4216           {
4217                 start_anonymous (false, (ParametersCompiled) $2, false, GetLocation ($1));
4218           }
4219           block
4220           {
4221                 $$ = end_anonymous ((ParametersBlock) $4);
4222           }
4223         | ASYNC DELEGATE opt_anonymous_method_signature
4224           {
4225                 start_anonymous (false, (ParametersCompiled) $3, true, GetLocation ($1));
4226           }
4227           block
4228           {
4229                 $$ = end_anonymous ((ParametersBlock) $5);
4230           }
4231         ;
4232
4233 opt_anonymous_method_signature
4234         :
4235           {
4236                 $$ = ParametersCompiled.Undefined;
4237           }
4238         | anonymous_method_signature
4239         ;
4240
4241 anonymous_method_signature
4242         : OPEN_PARENS
4243           {
4244                 valid_param_mod = ParameterModifierType.Ref | ParameterModifierType.Out;
4245           }
4246           opt_formal_parameter_list CLOSE_PARENS
4247           {
4248                 valid_param_mod = 0;
4249                 $$ = $3;
4250           }
4251         ;
4252
4253 default_value_expression
4254         : DEFAULT open_parens_any type CLOSE_PARENS
4255           {
4256                 if (lang_version < LanguageVersion.ISO_2)
4257                         FeatureIsNotAvailable (GetLocation ($1), "default value expression");
4258
4259                 $$ = new DefaultValueExpression ((Expression) $3, GetLocation ($1));
4260                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
4261           }
4262         ;
4263
4264 unary_expression
4265         : primary_expression
4266         | BANG prefixed_unary_expression
4267           {
4268                 $$ = new Unary (Unary.Operator.LogicalNot, (Expression) $2, GetLocation ($1));
4269           }
4270         | TILDE prefixed_unary_expression
4271           {
4272                 $$ = new Unary (Unary.Operator.OnesComplement, (Expression) $2, GetLocation ($1));
4273           }
4274         | OPEN_PARENS_CAST type CLOSE_PARENS prefixed_unary_expression
4275           {
4276                 $$ = new Cast ((FullNamedExpression) $2, (Expression) $4, GetLocation ($1));
4277                 lbag.AddLocation ($$, GetLocation ($3));
4278           }
4279         | AWAIT prefixed_unary_expression
4280           {
4281                 if (!async_block) {
4282                          if (current_anonymous_method is LambdaExpression) {
4283                                 report.Error (4034, GetLocation ($1),
4284                                         "The `await' operator can only be used when its containing lambda expression is marked with the `async' modifier");
4285                         } else if (current_anonymous_method != null) {
4286                                 report.Error (4035, GetLocation ($1),
4287                                         "The `await' operator can only be used when its containing anonymous method is marked with the `async' modifier");
4288                         } else if (interactive_async != null) {
4289                                 current_block.Explicit.RegisterAsyncAwait ();
4290                                 interactive_async = true;
4291                         } else {
4292                                 report.Error (4033, GetLocation ($1),
4293                                         "The `await' operator can only be used when its containing method is marked with the `async' modifier");
4294                         }
4295                 } else {
4296                         current_block.Explicit.RegisterAsyncAwait ();
4297                 }
4298
4299                 $$ = new Await ((Expression) $2, GetLocation ($1));
4300           }
4301         | BANG error
4302           {
4303                 Error_SyntaxError (yyToken);
4304
4305                 $$ = new Unary (Unary.Operator.LogicalNot, null, GetLocation ($1));
4306           }
4307         | TILDE error
4308           {
4309                 Error_SyntaxError (yyToken);
4310
4311                 $$ = new Unary (Unary.Operator.OnesComplement, null, GetLocation ($1));
4312           }
4313         | OPEN_PARENS_CAST type CLOSE_PARENS error
4314           {
4315                 Error_SyntaxError (yyToken);
4316
4317                 $$ = new Cast ((FullNamedExpression) $2, null, GetLocation ($1));
4318                 lbag.AddLocation ($$, GetLocation ($3));
4319           }
4320         | AWAIT error
4321           {
4322                 Error_SyntaxError (yyToken);
4323
4324                 $$ = new Await (null, GetLocation ($1));
4325           }
4326         ;
4327
4328         //
4329         // The idea to split this out is from Rhys' grammar
4330         // to solve the problem with casts.
4331         //
4332 prefixed_unary_expression
4333         : unary_expression
4334         | PLUS prefixed_unary_expression
4335           {
4336                 $$ = new Unary (Unary.Operator.UnaryPlus, (Expression) $2, GetLocation ($1));
4337           }
4338         | MINUS prefixed_unary_expression
4339           {
4340                 $$ = new Unary (Unary.Operator.UnaryNegation, (Expression) $2, GetLocation ($1));
4341           }
4342         | OP_INC prefixed_unary_expression
4343           {
4344                 $$ = new UnaryMutator (UnaryMutator.Mode.PreIncrement, (Expression) $2, GetLocation ($1));
4345           }
4346         | OP_DEC prefixed_unary_expression
4347           {
4348                 $$ = new UnaryMutator (UnaryMutator.Mode.PreDecrement, (Expression) $2, GetLocation ($1));
4349           }
4350         | STAR prefixed_unary_expression
4351           {
4352                 $$ = new Indirection ((Expression) $2, GetLocation ($1));
4353           }
4354         | BITWISE_AND prefixed_unary_expression
4355           {
4356                 $$ = new Unary (Unary.Operator.AddressOf, (Expression) $2, GetLocation ($1));
4357           }
4358         | PLUS error
4359           {
4360                 Error_SyntaxError (yyToken);
4361
4362                 $$ = new Unary (Unary.Operator.UnaryPlus, null, GetLocation ($1));
4363           }
4364         | MINUS error
4365           {
4366                 Error_SyntaxError (yyToken);
4367
4368                 $$ = new Unary (Unary.Operator.UnaryNegation, null, GetLocation ($1));
4369           }
4370         | OP_INC error
4371           {
4372                 Error_SyntaxError (yyToken);
4373
4374                 $$ = new UnaryMutator (UnaryMutator.Mode.PreIncrement, null, GetLocation ($1));
4375           }
4376         | OP_DEC error
4377           {
4378                 Error_SyntaxError (yyToken);
4379
4380                 $$ = new UnaryMutator (UnaryMutator.Mode.PreDecrement, null, GetLocation ($1));
4381           }
4382         | STAR error
4383           {
4384                 Error_SyntaxError (yyToken);
4385
4386                 $$ = new Indirection (null, GetLocation ($1));
4387           }
4388         | BITWISE_AND error
4389           {
4390                 Error_SyntaxError (yyToken);
4391
4392                 $$ = new Unary (Unary.Operator.AddressOf, null, GetLocation ($1));
4393           }
4394         ;
4395
4396 multiplicative_expression
4397         : prefixed_unary_expression
4398         | multiplicative_expression STAR prefixed_unary_expression
4399           {
4400                 $$ = new Binary (Binary.Operator.Multiply, (Expression) $1, (Expression) $3);
4401                 lbag.AddLocation ($$, GetLocation ($2));
4402           }
4403         | multiplicative_expression DIV prefixed_unary_expression
4404           {
4405                 $$ = new Binary (Binary.Operator.Division, (Expression) $1, (Expression) $3);
4406                 lbag.AddLocation ($$, GetLocation ($2));
4407           }
4408         | multiplicative_expression PERCENT prefixed_unary_expression
4409           {
4410                 $$ = new Binary (Binary.Operator.Modulus, (Expression) $1, (Expression) $3);
4411                 lbag.AddLocation ($$, GetLocation ($2));
4412           }
4413         | multiplicative_expression STAR error
4414           {
4415                 Error_SyntaxError (yyToken);
4416
4417                 $$ = new Binary (Binary.Operator.Multiply, (Expression) $1, null);
4418                 lbag.AddLocation ($$, GetLocation ($2));
4419           }
4420         | multiplicative_expression DIV error
4421           {
4422                 Error_SyntaxError (yyToken);
4423
4424                 $$ = new Binary (Binary.Operator.Division, (Expression) $1, null);
4425                 lbag.AddLocation ($$, GetLocation ($2));
4426           }
4427         | multiplicative_expression PERCENT error
4428           {
4429                 Error_SyntaxError (yyToken);
4430
4431                 $$ = new Binary (Binary.Operator.Modulus, (Expression) $1, null);
4432                 lbag.AddLocation ($$, GetLocation ($2));
4433           }
4434         ;
4435
4436 additive_expression
4437         : multiplicative_expression
4438         | additive_expression PLUS multiplicative_expression
4439           {
4440                 $$ = new Binary (Binary.Operator.Addition, (Expression) $1, (Expression) $3);
4441                 lbag.AddLocation ($$, GetLocation ($2));
4442           }
4443         | additive_expression MINUS multiplicative_expression
4444           {
4445                 $$ = new Binary (Binary.Operator.Subtraction, (Expression) $1, (Expression) $3);
4446                 lbag.AddLocation ($$, GetLocation ($2));
4447           }
4448         | additive_expression PLUS error
4449           {
4450                 Error_SyntaxError (yyToken);
4451
4452                 $$ = new Binary (Binary.Operator.Addition, (Expression) $1, null);
4453                 lbag.AddLocation ($$, GetLocation ($2));
4454           }
4455         | additive_expression MINUS error
4456           {
4457                 Error_SyntaxError (yyToken);
4458
4459                 $$ = new Binary (Binary.Operator.Subtraction, (Expression) $1, null);
4460                 lbag.AddLocation ($$, GetLocation ($2));
4461           }
4462         | additive_expression AS type
4463           {
4464                 $$ = new As ((Expression) $1, (Expression) $3, GetLocation ($2));
4465           }
4466         | additive_expression IS pattern_type_expr opt_identifier
4467           {
4468                 var is_expr = new Is ((Expression) $1, (Expression) $3, GetLocation ($2));
4469                 if ($4 != null) {
4470                         if (lang_version != LanguageVersion.Experimental)
4471                                 FeatureIsNotAvailable (GetLocation ($4), "type pattern matching");
4472
4473                         var lt = (LocatedToken) $4;
4474                         is_expr.Variable = new LocalVariable (current_block, lt.Value, lt.Location);
4475                         current_block.AddLocalName (is_expr.Variable);
4476                 }
4477
4478                 $$ = is_expr;
4479           }
4480         | additive_expression IS pattern_expr
4481           {
4482                 var is_expr = new Is ((Expression) $1, (Expression) $3, GetLocation ($2));
4483                 if (lang_version != LanguageVersion.Experimental)
4484                         FeatureIsNotAvailable (GetLocation ($2), "pattern matching");
4485
4486                 $$ = is_expr;
4487           }
4488         | additive_expression AS error
4489           {
4490                 Error_SyntaxError (yyToken);
4491
4492                 $$ = new As ((Expression) $1, null, GetLocation ($2));
4493           }
4494         | additive_expression IS error
4495           {
4496                 Error_SyntaxError (yyToken);
4497
4498                 $$ = new Is ((Expression) $1, null, GetLocation ($2));
4499           }
4500         | AWAIT IS type
4501           {
4502                 var lt = (LocatedToken) $1;
4503                 $$ = new Is (new SimpleName (lt.Value, lt.Location), (Expression) $3, GetLocation ($2));
4504           }
4505         | AWAIT AS type
4506           {
4507                 var lt = (LocatedToken) $1;
4508                 $$ = new As (new SimpleName (lt.Value, lt.Location), (Expression) $3, GetLocation ($2));
4509           }
4510         ;
4511
4512 pattern_type_expr
4513         : variable_type
4514         ;
4515
4516 pattern_expr
4517         : literal
4518         | PLUS prefixed_unary_expression
4519           {
4520                 $$ = new Unary (Unary.Operator.UnaryPlus, (Expression) $2, GetLocation ($1));
4521           }
4522         | MINUS prefixed_unary_expression
4523           {
4524                 $$ = new Unary (Unary.Operator.UnaryNegation, (Expression) $2, GetLocation ($1));
4525           }
4526         | sizeof_expression
4527         | default_value_expression
4528         | OPEN_PARENS_CAST type CLOSE_PARENS prefixed_unary_expression
4529           {
4530                 $$ = new Cast ((FullNamedExpression) $2, (Expression) $4, GetLocation ($1));
4531                 lbag.AddLocation ($$, GetLocation ($3));
4532           }
4533         | STAR
4534           {
4535                 $$ = new WildcardPattern (GetLocation ($1));
4536           }
4537         | pattern_expr_invocation
4538         | pattern_property
4539         ;
4540
4541 pattern_expr_invocation
4542         : type_name_expression OPEN_PARENS opt_pattern_list CLOSE_PARENS
4543           {
4544                 $$ = new RecursivePattern ((ATypeNameExpression) $1, (Arguments) $3, GetLocation ($2));
4545           }
4546         ;
4547
4548 pattern_property
4549         : type_name_expression OPEN_BRACE pattern_property_list CLOSE_BRACE
4550           {
4551                 $$ = new PropertyPattern ((ATypeNameExpression) $1, (List<PropertyPatternMember>) $3, GetLocation ($2));
4552           }
4553         ;
4554
4555 pattern_property_list
4556         : pattern_property_entry
4557           {
4558                 var list = new List<PropertyPatternMember> ();
4559                 list.Add ((PropertyPatternMember) $1);
4560                 $$ = list;
4561           }
4562         | pattern_property_list COMMA pattern_property_entry
4563           {
4564                 var list = (List<PropertyPatternMember>) $1;
4565                 list.Add ((PropertyPatternMember) $3);
4566                 $$ = list;
4567           }
4568         ;
4569
4570 pattern_property_entry
4571         : identifier_inside_body IS pattern
4572           {
4573                 var lt = (LocatedToken) $1;
4574                 $$ = new PropertyPatternMember (lt.Value, (Expression) $3, lt.Location);
4575           }
4576         ;
4577
4578 pattern
4579         : pattern_expr
4580         | pattern_type_expr opt_identifier
4581           {
4582                 if ($2 != null) {
4583                         var lt = (LocatedToken) $2;
4584                         var variable = new LocalVariable (current_block, lt.Value, lt.Location);
4585                         current_block.AddLocalName (variable);
4586                 }
4587           }
4588         ;
4589
4590 opt_pattern_list
4591         : /* empty */
4592           {
4593                 $$ = new Arguments (0);
4594           }
4595         | pattern_list
4596         ;
4597
4598 pattern_list
4599         : pattern_argument
4600           {
4601                 Arguments args = new Arguments (4);
4602                 args.Add ((Argument) $1);
4603                 $$ = args;
4604           }
4605         | pattern_list COMMA pattern_argument
4606           {
4607                 Arguments args = (Arguments) $1;
4608                 if (args [args.Count - 1] is NamedArgument && !($3 is NamedArgument))
4609                         Error_NamedArgumentExpected ((NamedArgument) args [args.Count - 1]);
4610
4611                 args.Add ((Argument) $3);
4612                 $$ = args;
4613           }
4614         ;
4615
4616 pattern_argument
4617         : pattern
4618           {
4619                 $$ = new Argument ((Expression) $1);
4620           }
4621         | IDENTIFIER COLON pattern
4622           {
4623                 var lt = (LocatedToken) $1;
4624                 $$ = new NamedArgument (lt.Value, lt.Location, (Expression) $3);
4625           }
4626         ;
4627
4628 shift_expression
4629         : additive_expression
4630         | shift_expression OP_SHIFT_LEFT additive_expression
4631           {
4632                 $$ = new Binary (Binary.Operator.LeftShift, (Expression) $1, (Expression) $3);
4633                 lbag.AddLocation ($$, GetLocation ($2));
4634           }
4635         | shift_expression OP_SHIFT_RIGHT additive_expression
4636           {
4637                 $$ = new Binary (Binary.Operator.RightShift, (Expression) $1, (Expression) $3);
4638                 lbag.AddLocation ($$, GetLocation ($2));
4639           }
4640         | shift_expression OP_SHIFT_LEFT error
4641           {
4642                 Error_SyntaxError (yyToken);
4643
4644                 $$ = new Binary (Binary.Operator.LeftShift, (Expression) $1, null);
4645                 lbag.AddLocation ($$, GetLocation ($2));
4646           }
4647         | shift_expression OP_SHIFT_RIGHT error
4648           {
4649                 Error_SyntaxError (yyToken);
4650
4651                 $$ = new Binary (Binary.Operator.RightShift, (Expression) $1, null);
4652                 lbag.AddLocation ($$, GetLocation ($2));
4653           }
4654         ;
4655
4656 relational_expression
4657         : shift_expression
4658         | relational_expression OP_LT shift_expression
4659           {
4660                 $$ = new Binary (Binary.Operator.LessThan, (Expression) $1, (Expression) $3);
4661                 lbag.AddLocation ($$, GetLocation ($2));
4662           }
4663         | relational_expression OP_GT shift_expression
4664           {
4665                 $$ = new Binary (Binary.Operator.GreaterThan, (Expression) $1, (Expression) $3);
4666                 lbag.AddLocation ($$, GetLocation ($2));
4667           }
4668         | relational_expression OP_LE shift_expression
4669           {
4670                 $$ = new Binary (Binary.Operator.LessThanOrEqual, (Expression) $1, (Expression) $3);
4671                 lbag.AddLocation ($$, GetLocation ($2));
4672           }
4673         | relational_expression OP_GE shift_expression
4674           {
4675                 $$ = new Binary (Binary.Operator.GreaterThanOrEqual, (Expression) $1, (Expression) $3);
4676                 lbag.AddLocation ($$, GetLocation ($2));
4677           }
4678         | relational_expression OP_LT error
4679           {
4680                 Error_SyntaxError (yyToken);
4681
4682                 $$ = new Binary (Binary.Operator.LessThan, (Expression) $1, null);
4683                 lbag.AddLocation ($$, GetLocation ($2));
4684           }
4685         | relational_expression OP_GT error
4686           {
4687                 Error_SyntaxError (yyToken);
4688
4689                 $$ = new Binary (Binary.Operator.GreaterThan, (Expression) $1, null);
4690                 lbag.AddLocation ($$, GetLocation ($2));
4691           }
4692         | relational_expression OP_LE error
4693           {
4694                 Error_SyntaxError (yyToken);
4695
4696                 $$ = new Binary (Binary.Operator.LessThanOrEqual, (Expression) $1, null);
4697                 lbag.AddLocation ($$, GetLocation ($2));
4698           }
4699         | relational_expression OP_GE error
4700           {
4701                 Error_SyntaxError (yyToken);
4702
4703                 $$ = new Binary (Binary.Operator.GreaterThanOrEqual, (Expression) $1, null);
4704                 lbag.AddLocation ($$, GetLocation ($2));
4705           }
4706         ;
4707
4708 equality_expression
4709         : relational_expression
4710         | equality_expression OP_EQ relational_expression
4711           {
4712                 $$ = new Binary (Binary.Operator.Equality, (Expression) $1, (Expression) $3);
4713                 lbag.AddLocation ($$, GetLocation ($2));
4714           }
4715         | equality_expression OP_NE relational_expression
4716           {
4717                 $$ = new Binary (Binary.Operator.Inequality, (Expression) $1, (Expression) $3);
4718                 lbag.AddLocation ($$, GetLocation ($2));
4719           }
4720         | equality_expression OP_EQ error
4721           {
4722                 Error_SyntaxError (yyToken);
4723
4724                 $$ = new Binary (Binary.Operator.Equality, (Expression) $1, null);
4725                 lbag.AddLocation ($$, GetLocation ($2));
4726           }
4727         | equality_expression OP_NE error
4728           {
4729                 Error_SyntaxError (yyToken);
4730
4731                 $$ = new Binary (Binary.Operator.Inequality, (Expression) $1, null);
4732                 lbag.AddLocation ($$, GetLocation ($2));
4733           }
4734         ;
4735
4736 and_expression
4737         : equality_expression
4738         | and_expression BITWISE_AND equality_expression
4739           {
4740                 $$ = new Binary (Binary.Operator.BitwiseAnd, (Expression) $1, (Expression) $3);
4741                 lbag.AddLocation ($$, GetLocation ($2));
4742           }
4743         | and_expression BITWISE_AND error
4744           {
4745                 Error_SyntaxError (yyToken);
4746
4747                 $$ = new Binary (Binary.Operator.BitwiseAnd, (Expression) $1, null);
4748                 lbag.AddLocation ($$, GetLocation ($2));
4749           }
4750         ;
4751
4752 exclusive_or_expression
4753         : and_expression
4754         | exclusive_or_expression CARRET and_expression
4755           {
4756                 $$ = new Binary (Binary.Operator.ExclusiveOr, (Expression) $1, (Expression) $3);
4757                 lbag.AddLocation ($$, GetLocation ($2));
4758           }
4759         | exclusive_or_expression CARRET error
4760           {
4761                 Error_SyntaxError (yyToken);
4762
4763                 $$ = new Binary (Binary.Operator.ExclusiveOr, (Expression) $1, null);
4764                 lbag.AddLocation ($$, GetLocation ($2));
4765           }
4766         ;
4767
4768 inclusive_or_expression
4769         : exclusive_or_expression
4770         | inclusive_or_expression BITWISE_OR exclusive_or_expression
4771           {
4772                 $$ = new Binary (Binary.Operator.BitwiseOr, (Expression) $1, (Expression) $3);
4773                 lbag.AddLocation ($$, GetLocation ($2));
4774           }
4775         | inclusive_or_expression BITWISE_OR error
4776           {
4777                 Error_SyntaxError (yyToken);
4778
4779                 $$ = new Binary (Binary.Operator.BitwiseOr, (Expression) $1, null);
4780                 lbag.AddLocation ($$, GetLocation ($2));
4781           }
4782         ;
4783
4784 conditional_and_expression
4785         : inclusive_or_expression
4786         | conditional_and_expression OP_AND inclusive_or_expression
4787           {
4788                 $$ = new Binary (Binary.Operator.LogicalAnd, (Expression) $1, (Expression) $3);
4789                 lbag.AddLocation ($$, GetLocation ($2));
4790           }
4791         | conditional_and_expression OP_AND error
4792           {
4793                 Error_SyntaxError (yyToken);
4794
4795                 $$ = new Binary (Binary.Operator.LogicalAnd, (Expression) $1, null);
4796                 lbag.AddLocation ($$, GetLocation ($2));
4797           }
4798         ;
4799
4800 conditional_or_expression
4801         : conditional_and_expression
4802         | conditional_or_expression OP_OR conditional_and_expression
4803           {
4804                 $$ = new Binary (Binary.Operator.LogicalOr, (Expression) $1, (Expression) $3);
4805                 lbag.AddLocation ($$, GetLocation ($2));
4806           }
4807         | conditional_or_expression OP_OR error
4808           {
4809                 Error_SyntaxError (yyToken);
4810
4811                 $$ = new Binary (Binary.Operator.LogicalOr, (Expression) $1, null);
4812                 lbag.AddLocation ($$, GetLocation ($2));
4813           }
4814         ;
4815
4816 null_coalescing_expression
4817         : conditional_or_expression
4818         | conditional_or_expression OP_COALESCING null_coalescing_expression
4819           {
4820                 if (lang_version < LanguageVersion.ISO_2)
4821                         FeatureIsNotAvailable (GetLocation ($2), "null coalescing operator");
4822
4823                 $$ = new Nullable.NullCoalescingOperator ((Expression) $1, (Expression) $3);
4824                 lbag.AddLocation ($$, GetLocation ($2));
4825           }
4826         ;
4827
4828 conditional_expression
4829         : null_coalescing_expression
4830         | null_coalescing_expression INTERR expression COLON expression
4831           {
4832                 $$ = new Conditional (new BooleanExpression ((Expression) $1), (Expression) $3, (Expression) $5, GetLocation ($2));
4833                 lbag.AddLocation ($$, GetLocation ($4));
4834           }
4835         | null_coalescing_expression INTERR expression error
4836           {
4837                 Error_SyntaxError (yyToken);
4838
4839                 $$ = new Conditional (new BooleanExpression ((Expression) $1), (Expression) $3, null, GetLocation ($2));
4840           }
4841         | null_coalescing_expression INTERR expression COLON error
4842           {
4843                 Error_SyntaxError (yyToken);
4844
4845                 $$ = new Conditional (new BooleanExpression ((Expression) $1), (Expression) $3, null, GetLocation ($2));
4846                 lbag.AddLocation ($$, GetLocation ($4));
4847           }
4848         | null_coalescing_expression INTERR expression COLON CLOSE_BRACE
4849           {
4850                 Error_SyntaxError (Token.CLOSE_BRACE);
4851
4852                 $$ = new Conditional (new BooleanExpression ((Expression) $1), (Expression) $3, null, GetLocation ($2));
4853                 lbag.AddLocation ($$, GetLocation ($4));
4854                 lexer.putback ('}');
4855           }
4856         ;
4857
4858 assignment_expression
4859         : prefixed_unary_expression ASSIGN expression
4860           {
4861                 $$ = new SimpleAssign ((Expression) $1, (Expression) $3);
4862                 lbag.AddLocation ($$, GetLocation ($2));
4863           }
4864         | prefixed_unary_expression OP_MULT_ASSIGN expression
4865           {
4866                 $$ = new CompoundAssign (Binary.Operator.Multiply, (Expression) $1, (Expression) $3);
4867                 lbag.AddLocation ($$, GetLocation ($2));
4868           }
4869         | prefixed_unary_expression OP_DIV_ASSIGN expression
4870           {
4871                 $$ = new CompoundAssign (Binary.Operator.Division, (Expression) $1, (Expression) $3);
4872                 lbag.AddLocation ($$, GetLocation ($2));
4873           }
4874         | prefixed_unary_expression OP_MOD_ASSIGN expression
4875           {
4876                 $$ = new CompoundAssign (Binary.Operator.Modulus, (Expression) $1, (Expression) $3);
4877                 lbag.AddLocation ($$, GetLocation ($2));
4878           }
4879         | prefixed_unary_expression OP_ADD_ASSIGN expression
4880           {
4881                 $$ = new CompoundAssign (Binary.Operator.Addition, (Expression) $1, (Expression) $3);
4882                 lbag.AddLocation ($$, GetLocation ($2));
4883           }
4884         | prefixed_unary_expression OP_SUB_ASSIGN expression
4885           {
4886                 $$ = new CompoundAssign (Binary.Operator.Subtraction, (Expression) $1, (Expression) $3);
4887                 lbag.AddLocation ($$, GetLocation ($2));
4888           }
4889         | prefixed_unary_expression OP_SHIFT_LEFT_ASSIGN expression
4890           {
4891                 $$ = new CompoundAssign (Binary.Operator.LeftShift, (Expression) $1, (Expression) $3);
4892                 lbag.AddLocation ($$, GetLocation ($2));
4893           }
4894         | prefixed_unary_expression OP_SHIFT_RIGHT_ASSIGN expression
4895           {
4896                 $$ = new CompoundAssign (Binary.Operator.RightShift, (Expression) $1, (Expression) $3);
4897                 lbag.AddLocation ($$, GetLocation ($2));
4898           }
4899         | prefixed_unary_expression OP_AND_ASSIGN expression
4900           {
4901                 $$ = new CompoundAssign (Binary.Operator.BitwiseAnd, (Expression) $1, (Expression) $3);
4902                 lbag.AddLocation ($$, GetLocation ($2));
4903           }
4904         | prefixed_unary_expression OP_OR_ASSIGN expression
4905           {
4906                 $$ = new CompoundAssign (Binary.Operator.BitwiseOr, (Expression) $1, (Expression) $3);
4907                 lbag.AddLocation ($$, GetLocation ($2));
4908           }
4909         | prefixed_unary_expression OP_XOR_ASSIGN expression
4910           {
4911                 $$ = new CompoundAssign (Binary.Operator.ExclusiveOr, (Expression) $1, (Expression) $3);
4912                 lbag.AddLocation ($$, GetLocation ($2));
4913           }
4914         ;
4915
4916 lambda_parameter_list
4917         : lambda_parameter
4918           {
4919                 var pars = new List<Parameter> (4);
4920                 pars.Add ((Parameter) $1);
4921
4922                 $$ = pars;
4923           }
4924         | lambda_parameter_list COMMA lambda_parameter
4925           {
4926                 var pars = (List<Parameter>) $1;
4927                 Parameter p = (Parameter)$3;
4928                 if (pars[0].GetType () != p.GetType ()) {
4929                         report.Error (748, p.Location, "All lambda parameters must be typed either explicitly or implicitly");
4930                 }
4931
4932                 pars.Add (p);
4933                 $$ = pars;
4934           }
4935         ;
4936
4937 lambda_parameter
4938         : parameter_modifier parameter_type identifier_inside_body
4939           {
4940                 var lt = (LocatedToken) $3;
4941
4942                 $$ = new Parameter ((FullNamedExpression) $2, lt.Value, (Parameter.Modifier) $1, null, lt.Location);
4943           }
4944         | parameter_type identifier_inside_body
4945           {
4946                 var lt = (LocatedToken) $2;
4947
4948                 $$ = new Parameter ((FullNamedExpression) $1, lt.Value, Parameter.Modifier.NONE, null, lt.Location);
4949           }
4950         | IDENTIFIER
4951           {
4952                 var lt = (LocatedToken) $1;
4953                 $$ = new ImplicitLambdaParameter (lt.Value, lt.Location);
4954           }
4955         | AWAIT
4956           {
4957                 var lt = (LocatedToken) Error_AwaitAsIdentifier ($1);
4958                 $$ = new ImplicitLambdaParameter (lt.Value, lt.Location);
4959           }
4960         ;
4961
4962 opt_lambda_parameter_list
4963         : /* empty */                   { $$ = ParametersCompiled.EmptyReadOnlyParameters; }
4964         | lambda_parameter_list         {
4965                 var pars_list = (List<Parameter>) $1;
4966                 $$ = new ParametersCompiled (pars_list.ToArray ());
4967           }
4968         ;
4969
4970 lambda_expression_body
4971         : {
4972                 start_block (Location.Null);
4973           }
4974           expression    // All expressions must handle error or current block won't be restored and breaking ast completely
4975           {
4976                 Block b = end_block (Location.Null);
4977                 b.IsCompilerGenerated = true;
4978                 b.AddStatement (new ContextualReturn ((Expression) $2));
4979                 $$ = b;
4980           }
4981         | block
4982         | error
4983           {
4984                 // Handles only cases like foo = x.FirstOrDefault (l => );
4985                 // where we must restore current_variable
4986                 Block b = end_block (Location.Null);
4987                 b.IsCompilerGenerated = true;
4988
4989                 Error_SyntaxError (yyToken);
4990                 $$ = null;
4991           }
4992         ;
4993
4994 expression_or_error
4995         : expression
4996         | error
4997           {
4998                 Error_SyntaxError (yyToken);
4999                 $$ = null;
5000           }
5001         ;
5002
5003 lambda_expression
5004         : IDENTIFIER ARROW
5005           {
5006                 var lt = (LocatedToken) $1;
5007                 Parameter p = new ImplicitLambdaParameter (lt.Value, lt.Location);
5008                 start_anonymous (true, new ParametersCompiled (p), false, lt.Location);
5009           }
5010           lambda_expression_body
5011           {
5012                 $$ = end_anonymous ((ParametersBlock) $4);
5013                 lbag.AddLocation ($$, GetLocation ($2));
5014           }
5015         | AWAIT ARROW
5016           {
5017                 var lt = (LocatedToken) Error_AwaitAsIdentifier ($1);
5018                 Parameter p = new ImplicitLambdaParameter (lt.Value, lt.Location);
5019                 start_anonymous (true, new ParametersCompiled (p), false, lt.Location);
5020           }
5021           lambda_expression_body
5022           {
5023                 $$ = end_anonymous ((ParametersBlock) $4);
5024                 lbag.AddLocation ($$, GetLocation ($2));
5025           }
5026         | ASYNC identifier_inside_body ARROW
5027           {
5028                 var lt = (LocatedToken) $2;
5029                 Parameter p = new ImplicitLambdaParameter (lt.Value, lt.Location);
5030                 start_anonymous (true, new ParametersCompiled (p), true, lt.Location);
5031           }
5032           lambda_expression_body
5033           {
5034                 $$ = end_anonymous ((ParametersBlock) $5);
5035                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($3));
5036           }
5037         | OPEN_PARENS_LAMBDA
5038           {
5039                 valid_param_mod = ParameterModifierType.Ref | ParameterModifierType.Out;
5040           }
5041           opt_lambda_parameter_list CLOSE_PARENS ARROW
5042           {
5043                 valid_param_mod = 0;
5044                 start_anonymous (true, (ParametersCompiled) $3, false, GetLocation ($1));
5045           }
5046           lambda_expression_body
5047           {
5048                 $$ = end_anonymous ((ParametersBlock) $7);
5049                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($4), GetLocation ($5));
5050           }
5051         | ASYNC OPEN_PARENS_LAMBDA
5052           {
5053                 valid_param_mod = ParameterModifierType.Ref | ParameterModifierType.Out;
5054           }
5055           opt_lambda_parameter_list CLOSE_PARENS ARROW
5056           {
5057                 valid_param_mod = 0;
5058                 start_anonymous (true, (ParametersCompiled) $4, true, GetLocation ($1));
5059           }
5060           lambda_expression_body
5061           {
5062                 $$ = end_anonymous ((ParametersBlock) $8);
5063                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($2), GetLocation ($5), GetLocation ($6));
5064           }
5065         ;
5066
5067 expression
5068         : assignment_expression
5069         | non_assignment_expression
5070         ;
5071
5072 non_assignment_expression
5073         : conditional_expression
5074         | lambda_expression
5075         | query_expression
5076         | ARGLIST
5077           {
5078                 $$ = new ArglistAccess (GetLocation ($1));
5079           }
5080         ;
5081
5082 undocumented_expressions
5083         : REFVALUE OPEN_PARENS non_assignment_expression COMMA type CLOSE_PARENS
5084           {
5085                 $$ = new RefValueExpr ((Expression) $3, (FullNamedExpression) $5, GetLocation ($1));
5086                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4), GetLocation ($6));
5087           }
5088         | REFTYPE open_parens_any expression CLOSE_PARENS
5089           {
5090                 $$ = new RefTypeExpr ((Expression) $3, GetLocation ($1));
5091                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
5092           }
5093         | MAKEREF open_parens_any expression CLOSE_PARENS
5094           {
5095                 $$ = new MakeRefExpr ((Expression) $3, GetLocation ($1));
5096                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($4));
5097           }
5098         ;
5099
5100 constant_expression
5101         : expression
5102         ;
5103
5104 boolean_expression
5105         : expression
5106           {
5107                 $$ = new BooleanExpression ((Expression) $1);
5108           }
5109         ;
5110
5111 opt_primary_parameters
5112         : /* empty */
5113           {
5114                 $$ = null;
5115           }
5116         | primary_parameters
5117         ;
5118
5119 primary_parameters
5120         : OPEN_PARENS opt_formal_parameter_list CLOSE_PARENS
5121           {
5122                 $$ = $2;
5123
5124                 // Cannot use opt_formal_parameter_list because it can be shared instance for empty parameters
5125                 lbag.AppendToMember (current_container, GetLocation ($1), GetLocation ($3));
5126
5127                 if (lang_version != LanguageVersion.Experimental)
5128                         FeatureIsNotAvailable (GetLocation ($1), "primary constructor");
5129           }
5130         ;
5131
5132 opt_primary_parameters_with_class_base
5133         : /* empty */
5134           {
5135                 $$ = null;
5136           }
5137         | class_base
5138           {
5139                 $$ = null;
5140           }
5141         | primary_parameters
5142           {
5143                 $$ = $1;
5144           }
5145         | primary_parameters class_base
5146           {
5147                 $$ = $1;
5148           }
5149         | primary_parameters class_base OPEN_PARENS
5150           {
5151                 ++lexer.parsing_block;
5152                 current_type.PrimaryConstructorBaseArgumentsStart = GetLocation ($3);
5153           }
5154           opt_argument_list CLOSE_PARENS
5155           {
5156                 lbag.AppendToMember (current_container, GetLocation ($6));
5157                 current_type.PrimaryConstructorBaseArguments = (Arguments) $5;
5158                 --lexer.parsing_block;
5159
5160                 $$ = $1;
5161           }
5162         ;
5163
5164 //
5165 // 10 classes
5166 //
5167 class_declaration
5168         : opt_attributes
5169           opt_modifiers
5170           opt_partial
5171           CLASS
5172           {
5173           }
5174           type_declaration_name
5175           {
5176                 lexer.ConstraintsParsing = true;
5177
5178                 Class c = new Class (current_container, (MemberName) $6, (Modifiers) $2, (Attributes) $1);
5179                 if (((c.ModFlags & Modifiers.STATIC) != 0) && lang_version == LanguageVersion.ISO_1) {
5180                         FeatureIsNotAvailable (c.Location, "static classes");
5181                 }
5182
5183                 push_current_container (c, $3);
5184                 valid_param_mod = ParameterModifierType.PrimaryConstructor;
5185           }
5186           opt_primary_parameters_with_class_base
5187           opt_type_parameter_constraints_clauses
5188           {
5189                 valid_param_mod = 0;
5190                 lexer.ConstraintsParsing = false;
5191
5192                 if ($8 != null)
5193                         current_type.PrimaryConstructorParameters = (ParametersCompiled) $8;
5194
5195                 if ($9 != null)
5196                         current_container.SetConstraints ((List<Constraints>) $9);
5197                 lbag.AddMember (current_container, mod_locations, GetLocation ($4));
5198
5199                 if (doc_support) {
5200                         current_container.PartialContainer.DocComment = Lexer.consume_doc_comment ();
5201                         Lexer.doc_state = XmlCommentState.Allowed;
5202                 }
5203
5204                 lexer.parsing_modifiers = true;
5205           }
5206           OPEN_BRACE opt_class_member_declarations CLOSE_BRACE
5207           {
5208                 --lexer.parsing_declaration;
5209                 if (doc_support)
5210                         Lexer.doc_state = XmlCommentState.Allowed;
5211           }
5212           opt_semicolon
5213           {
5214                 if ($15 == null) {
5215                         lbag.AppendToMember (current_container, GetLocation ($11), GetLocation ($13));
5216                 } else {
5217                         lbag.AppendToMember (current_container, GetLocation ($11), GetLocation ($13), GetLocation ($15));
5218                 }
5219                 $$ = pop_current_class ();
5220           }
5221         ;
5222
5223 opt_partial
5224         : /* empty */
5225           { $$ = null; }
5226         | PARTIAL
5227           { $$ = $1; } // location
5228         ;
5229
5230 opt_modifiers
5231         : /* empty */
5232           {
5233             mod_locations = null;
5234                 $$ = ModifierNone;
5235                 lexer.parsing_modifiers = false;
5236           }
5237         | modifiers
5238           {
5239                 lexer.parsing_modifiers = false;
5240           }
5241         ;
5242
5243 modifiers
5244         : modifier
5245         | modifiers modifier
5246           {
5247                 var m1 = (Modifiers) $1;
5248                 var m2 = (Modifiers) $2;
5249
5250                 if ((m1 & m2) != 0) {
5251                         report.Error (1004, lexer.Location - ModifiersExtensions.Name (m2).Length,
5252                                 "Duplicate `{0}' modifier", ModifiersExtensions.Name (m2));
5253                 } else if ((m2 & Modifiers.AccessibilityMask) != 0 && (m1 & Modifiers.AccessibilityMask) != 0 &&
5254                         ((m2 | m1 & Modifiers.AccessibilityMask) != (Modifiers.PROTECTED | Modifiers.INTERNAL))) {
5255                         report.Error (107, lexer.Location - ModifiersExtensions.Name (m2).Length,
5256                                 "More than one protection modifier specified");
5257                 }
5258
5259                 $$ = m1 | m2;
5260           }
5261         ;
5262
5263 modifier
5264         : NEW
5265           {
5266                 $$ = Modifiers.NEW;
5267                 StoreModifierLocation ($$, GetLocation ($1));
5268
5269                 if (current_container.Kind == MemberKind.Namespace)
5270                         report.Error (1530, GetLocation ($1), "Keyword `new' is not allowed on namespace elements");
5271           }
5272         | PUBLIC
5273           {
5274                 $$ = Modifiers.PUBLIC;
5275                 StoreModifierLocation ($$, GetLocation ($1));
5276           }
5277         | PROTECTED
5278           {
5279                 $$ = Modifiers.PROTECTED;
5280                 StoreModifierLocation ($$, GetLocation ($1));
5281           }
5282         | INTERNAL
5283           {
5284                 $$ = Modifiers.INTERNAL;
5285                 StoreModifierLocation ($$, GetLocation ($1));
5286           }
5287         | PRIVATE
5288           {
5289                 $$ = Modifiers.PRIVATE;
5290                 StoreModifierLocation ($$, GetLocation ($1));
5291           }
5292         | ABSTRACT
5293           {
5294                 $$ = Modifiers.ABSTRACT;
5295                 StoreModifierLocation ($$, GetLocation ($1));
5296           }
5297         | SEALED
5298           {
5299                 $$ = Modifiers.SEALED;
5300                 StoreModifierLocation ($$, GetLocation ($1));
5301           }
5302         | STATIC
5303           {
5304                 $$ = Modifiers.STATIC;
5305                 StoreModifierLocation ($$, GetLocation ($1));
5306           }
5307         | READONLY
5308           {
5309                 $$ = Modifiers.READONLY;
5310                 StoreModifierLocation ($$, GetLocation ($1));
5311           }
5312         | VIRTUAL
5313           {
5314                 $$ = Modifiers.VIRTUAL;
5315                 StoreModifierLocation ($$, GetLocation ($1));
5316           }
5317         | OVERRIDE
5318           {
5319                 $$ = Modifiers.OVERRIDE;
5320                 StoreModifierLocation ($$, GetLocation ($1));
5321           }
5322         | EXTERN
5323           {
5324                 $$ = Modifiers.EXTERN;
5325                 StoreModifierLocation ($$, GetLocation ($1));
5326           }
5327         | VOLATILE
5328           {
5329                 $$ = Modifiers.VOLATILE;
5330                 StoreModifierLocation ($$, GetLocation ($1));
5331           }
5332         | UNSAFE
5333           {
5334                 $$ = Modifiers.UNSAFE;
5335                 StoreModifierLocation ($$, GetLocation ($1));
5336                 if (!settings.Unsafe)
5337                         Error_UnsafeCodeNotAllowed (GetLocation ($1));
5338           }
5339         | ASYNC
5340           {
5341                 $$ = Modifiers.ASYNC;
5342                 StoreModifierLocation ($$, GetLocation ($1));
5343           }
5344         ;
5345
5346 opt_class_base
5347         : /* empty */
5348         | class_base
5349         ;
5350
5351 class_base
5352         : COLON type_list
5353          {
5354                 current_type.SetBaseTypes ((List<FullNamedExpression>) $2);
5355          }
5356         | COLON type_list error
5357           {
5358                 Error_SyntaxError (yyToken);
5359
5360                 current_type.SetBaseTypes ((List<FullNamedExpression>) $2);
5361           }
5362         ;
5363
5364 opt_type_parameter_constraints_clauses
5365         : /* empty */
5366         | type_parameter_constraints_clauses
5367           {
5368                 $$ = $1;
5369           }
5370         ;
5371
5372 type_parameter_constraints_clauses
5373         : type_parameter_constraints_clause
5374           {
5375                 var constraints = new List<Constraints> (1);
5376                 constraints.Add ((Constraints) $1);
5377                 $$ = constraints;
5378           }
5379         | type_parameter_constraints_clauses type_parameter_constraints_clause
5380           {
5381                 var constraints = (List<Constraints>) $1;
5382                 Constraints new_constraint = (Constraints)$2;
5383
5384                 foreach (Constraints c in constraints) {
5385                         if (new_constraint.TypeParameter.Value == c.TypeParameter.Value) {
5386                                 report.Error (409, new_constraint.Location,
5387                                         "A constraint clause has already been specified for type parameter `{0}'",
5388                                         new_constraint.TypeParameter.Value);
5389                         }
5390                 }
5391
5392                 constraints.Add (new_constraint);
5393                 $$ = constraints;
5394           }
5395         ;
5396
5397 type_parameter_constraints_clause
5398         : WHERE IDENTIFIER COLON type_parameter_constraints
5399           {
5400                 var lt = (LocatedToken) $2;
5401                 $$ = new Constraints (new SimpleMemberName (lt.Value, lt.Location), (List<FullNamedExpression>) $4, GetLocation ($1));
5402                 lbag.AddLocation ($$, GetLocation ($3));
5403           }
5404         | WHERE IDENTIFIER error
5405           {
5406                 Error_SyntaxError (yyToken);
5407
5408                 var lt = (LocatedToken) $2;
5409                 $$ = new Constraints (new SimpleMemberName (lt.Value, lt.Location), null, GetLocation ($1));
5410           }
5411         ;
5412
5413 type_parameter_constraints
5414         : type_parameter_constraint
5415           {
5416                 var constraints = new List<FullNamedExpression> (1);
5417                 constraints.Add ((FullNamedExpression) $1);
5418                 $$ = constraints;
5419           }
5420         | type_parameter_constraints COMMA type_parameter_constraint
5421           {
5422                 var constraints = (List<FullNamedExpression>) $1;
5423                 var prev = constraints [constraints.Count - 1] as SpecialContraintExpr;
5424                 if (prev != null && (prev.Constraint & SpecialConstraint.Constructor) != 0) {
5425                         report.Error (401, GetLocation ($2), "The `new()' constraint must be the last constraint specified");
5426                 }
5427
5428                 prev = $3 as SpecialContraintExpr;
5429                 if (prev != null) {
5430                         if ((prev.Constraint & (SpecialConstraint.Class | SpecialConstraint.Struct)) != 0) {
5431                                 report.Error (449, prev.Location, "The `class' or `struct' constraint must be the first constraint specified");
5432                         } else {
5433                                 prev = constraints [0] as SpecialContraintExpr;
5434                                 if (prev != null && (prev.Constraint & SpecialConstraint.Struct) != 0) {
5435                                         report.Error (451, GetLocation ($3), "The `new()' constraint cannot be used with the `struct' constraint");
5436                                 }
5437                         }
5438                 }
5439
5440                 constraints.Add ((FullNamedExpression) $3);
5441                 $$ = constraints;
5442           }
5443         ;
5444
5445 type_parameter_constraint
5446         : type
5447           {
5448                 if ($1 is ComposedCast)
5449                         report.Error (706, GetLocation ($1), "Invalid constraint type `{0}'", ((ComposedCast)$1).GetSignatureForError ());
5450
5451                 $$ = $1;
5452           }
5453         | NEW OPEN_PARENS CLOSE_PARENS
5454           {
5455                 $$ = new SpecialContraintExpr (SpecialConstraint.Constructor, GetLocation ($1));
5456                 lbag.AddLocation ($$, GetLocation ($2), GetLocation ($3));
5457           }
5458         | CLASS
5459           {
5460                 $$ = new SpecialContraintExpr (SpecialConstraint.Class, GetLocation ($1));
5461           }
5462         | STRUCT
5463           {
5464                 $$ = new SpecialContraintExpr (SpecialConstraint.Struct, GetLocation ($1));
5465           }
5466         ;
5467
5468 opt_type_parameter_variance
5469         : /* empty */
5470           {
5471                 $$ = null;
5472           }
5473         | type_parameter_variance
5474           {
5475                 if (lang_version <= LanguageVersion.V_3)
5476                         FeatureIsNotAvailable (lexer.Location, "generic type variance");
5477
5478                 $$ = $1;
5479           }
5480         ;
5481
5482 type_parameter_variance
5483         : OUT
5484           {
5485                 $$ = new VarianceDecl (Variance.Covariant, GetLocation ($1));
5486           }
5487         | IN
5488           {
5489                 $$ = new VarianceDecl (Variance.Contravariant, GetLocation ($1));
5490           }
5491         ;
5492
5493 //
5494 // Statements (8.2)
5495 //
5496
5497 //
5498 // A block is "contained" on the following places:
5499 //      method_body
5500 //      property_declaration as part of the accessor body (get/set)
5501 //      operator_declaration
5502 //      constructor_declaration
5503 //      destructor_declaration
5504 //      event_declaration as part of add_accessor_declaration or remove_accessor_declaration
5505 //
5506 block
5507         : OPEN_BRACE
5508           {
5509                 ++lexer.parsing_block;
5510                 start_block (GetLocation ($1));
5511           }
5512           opt_statement_list block_end
5513           {
5514                 $$ = $4;
5515           }
5516         ;
5517
5518 block_end
5519         : CLOSE_BRACE
5520           {
5521                 --lexer.parsing_block;
5522                 $$ = end_block (GetLocation ($1));
5523           }
5524         | COMPLETE_COMPLETION
5525           {
5526                 --lexer.parsing_block;
5527                 $$ = end_block (lexer.Location);
5528           }
5529         ;
5530
5531
5532 block_prepared
5533         : OPEN_BRACE
5534           {
5535                 ++lexer.parsing_block;
5536                 current_block.StartLocation = GetLocation ($1);
5537           }
5538           opt_statement_list CLOSE_BRACE
5539           {
5540                 --lexer.parsing_block;
5541                 $$ = end_block (GetLocation ($4));
5542           }
5543         ;
5544
5545 opt_statement_list
5546         : /* empty */
5547         | statement_list
5548         ;
5549
5550 statement_list
5551         : statement
5552         | statement_list statement
5553         ;
5554
5555 statement
5556         : block_variable_declaration
5557           {
5558                 current_block.AddStatement ((Statement) $1);
5559           }
5560         | valid_declaration_statement
5561           {
5562                 current_block.AddStatement ((Statement) $1);
5563           }
5564         | labeled_statement
5565         | error
5566           {
5567                 Error_SyntaxError (yyToken);
5568                 $$ = null;
5569           }
5570         ;
5571
5572 //
5573 // The interactive_statement and its derivatives are only
5574 // used to provide a special version of `expression_statement'
5575 // that has a side effect of assigning the expression to
5576 // $retval
5577 //
5578 interactive_statement_list
5579         : interactive_statement
5580         | interactive_statement_list interactive_statement
5581         ;
5582
5583 interactive_statement
5584         : block_variable_declaration
5585           {
5586                 current_block.AddStatement ((Statement) $1);
5587           }
5588         | interactive_valid_declaration_statement
5589           {
5590                 current_block.AddStatement ((Statement) $1);
5591           }
5592         | labeled_statement
5593         ;
5594
5595 valid_declaration_statement
5596         : block
5597         | empty_statement
5598         | expression_statement
5599         | selection_statement
5600         | iteration_statement
5601         | jump_statement
5602         | try_statement
5603         | checked_statement
5604         | unchecked_statement
5605         | lock_statement
5606         | using_statement
5607         | unsafe_statement
5608         | fixed_statement
5609         ;
5610
5611 interactive_valid_declaration_statement
5612         : block
5613         | empty_statement
5614         | interactive_expression_statement
5615         | selection_statement
5616         | iteration_statement
5617         | jump_statement
5618         | try_statement
5619         | checked_statement
5620         | unchecked_statement
5621         | lock_statement
5622         | using_statement
5623         | unsafe_statement
5624         | fixed_statement
5625         ;
5626
5627 embedded_statement
5628         : valid_declaration_statement
5629         | block_variable_declaration
5630           {
5631                   report.Error (1023, GetLocation ($1), "An embedded statement may not be a declaration or labeled statement");
5632                   $$ = null;
5633           }
5634         | labeled_statement
5635           {
5636                   report.Error (1023, GetLocation ($1), "An embedded statement may not be a declaration or labeled statement");
5637                   $$ = null;
5638           }
5639         | error
5640           {
5641                 Error_SyntaxError (yyToken);
5642                 $$ = new EmptyStatement (GetLocation ($1));
5643           }
5644         ;
5645
5646 empty_statement
5647         : SEMICOLON
5648           {
5649                 // Uses lexer.Location because semicolon location is not kept in quick mode
5650                 $$ = new EmptyStatement (lexer.Location);
5651           }
5652         ;
5653
5654 labeled_statement
5655         : identifier_inside_body COLON
5656           {
5657                 var lt = (LocatedToken) $1;
5658                 LabeledStatement labeled = new LabeledStatement (lt.Value, current_block, lt.Location);
5659                 lbag.AddLocation (labeled, GetLocation ($2));
5660                 current_block.AddLabel (labeled);
5661                 current_block.AddStatement (labeled);
5662           }
5663           statement
5664         ;
5665
5666 variable_type
5667         : variable_type_simple
5668         | variable_type_simple rank_specifiers
5669           {
5670                 if ($1 is VarExpr)
5671                         $1 = new SimpleName ("var", ((VarExpr) $1).Location);
5672
5673                 $$ = new ComposedCast ((FullNamedExpression) $1, (ComposedTypeSpecifier) $2);
5674           }
5675         ;
5676
5677 /*
5678  * The following is from Rhys' grammar:
5679  * > Types in local variable declarations must be recognized as
5680  * > expressions to prevent reduce/reduce errors in the grammar.
5681  * > The expressions are converted into types during semantic analysis.
5682  */
5683 variable_type_simple
5684         : type_name_expression opt_nullable
5685           {
5686                 // Ok, the above "primary_expression" is there to get rid of
5687                 // both reduce/reduce and shift/reduces in the grammar, it should
5688                 // really just be "type_name".  If you use type_name, a reduce/reduce
5689                 // creeps up.  If you use namespace_or_type_name (which is all we need
5690                 // really) two shift/reduces appear.
5691                 //
5692
5693                 // So the super-trick is that primary_expression
5694                 // can only be either a SimpleName or a MemberAccess.
5695                 // The MemberAccess case arises when you have a fully qualified type-name like :
5696                 // Foo.Bar.Blah i;
5697                 // SimpleName is when you have
5698                 // Blah i;
5699
5700                 var expr = (ATypeNameExpression) $1;
5701                 if ($2 == null) {
5702                         if (expr.Name == "var" && expr is SimpleName)
5703                                 $$ = new VarExpr (expr.Location);
5704                         else
5705                                 $$ = $1;
5706                 } else {
5707                         $$ = new ComposedCast (expr, (ComposedTypeSpecifier) $2);
5708                 }
5709           }
5710         | type_name_expression pointer_stars
5711           {
5712                 var expr = (ATypeNameExpression) $1;
5713                 $$ = new ComposedCast (expr, (ComposedTypeSpecifier) $2);
5714           }
5715         | builtin_type_expression
5716         | void_invalid
5717         ;
5718
5719 pointer_stars
5720         : pointer_star
5721         | pointer_star pointer_stars
5722           {
5723                 ((ComposedTypeSpecifier) $1).Next = (ComposedTypeSpecifier) $2;
5724                 $$ = $1;
5725           }
5726         ;
5727
5728 pointer_star
5729         : STAR
5730           {
5731                 $$ = ComposedTypeSpecifier.CreatePointer (GetLocation ($1));
5732           }
5733         ;
5734
5735 identifier_inside_body
5736         : IDENTIFIER
5737         | AWAIT
5738           {
5739                 $$ = Error_AwaitAsIdentifier ($1);
5740           }
5741         ;
5742
5743 block_variable_declaration
5744         : variable_type identifier_inside_body
5745           {
5746                 var lt = (LocatedToken) $2;
5747                 var li = new LocalVariable (current_block, lt.Value, lt.Location);
5748                 current_block.AddLocalName (li);
5749                 current_variable = new BlockVariable ((FullNamedExpression) $1, li);
5750           }
5751           opt_local_variable_initializer opt_variable_declarators SEMICOLON
5752           {
5753                 $$ = current_variable;
5754                 current_variable = null;
5755                 if ($4 != null)
5756                         lbag.AddLocation ($$, PopLocation (), GetLocation ($6));
5757                 else
5758                         lbag.AddLocation ($$, GetLocation ($6));
5759           }
5760         | CONST variable_type identifier_inside_body
5761           {
5762                 var lt = (LocatedToken) $3;
5763                 var li = new LocalVariable (current_block, lt.Value, LocalVariable.Flags.Constant, lt.Location);
5764                 current_block.AddLocalName (li);
5765                 current_variable = new BlockConstant ((FullNamedExpression) $2, li);
5766           }
5767           const_variable_initializer opt_const_declarators SEMICOLON
5768           {
5769                 $$ = current_variable;
5770                 current_variable = null;
5771                 lbag.AddLocation ($$, GetLocation ($1), GetLocation ($7));
5772           }
5773         ;
5774
5775 opt_local_variable_initializer
5776         : /* empty */
5777         | ASSIGN block_variable_initializer
5778           {
5779                 current_variable.Initializer = (Expression) $2;
5780                 PushLocation (GetLocation ($1));
5781                 $$ = current_variable;
5782           }
5783         | error
5784           {
5785                 if (yyToken == Token.OPEN_BRACKET_EXPR) {
5786                         report.Error (650, lexer.Location,
5787                                 "Syntax error, bad array declarator. To declare a managed array the rank specifier precedes the variable's identifier. To declare a fixed size buffer field, use the fixed keyword before the field type");
5788                 } else {
5789                         Error_SyntaxError (yyToken);
5790                 }
5791           }
5792         ;
5793
5794 opt_variable_declarators
5795         : /* empty */
5796         | variable_declarators
5797         ;
5798
5799 opt_using_or_fixed_variable_declarators
5800         : /* empty */
5801         | variable_declarators
5802           {
5803                 foreach (var d in current_variable.Declarators) {
5804                         if (d.Initializer == null)
5805                                 Error_MissingInitializer (d.Variable.Location);
5806                 }
5807           }
5808         ;
5809
5810 variable_declarators
5811         : variable_declarator
5812         | variable_declarators variable_declarator
5813         ;
5814
5815 variable_declarator
5816         : COMMA identifier_inside_body
5817           {
5818                 var lt = (LocatedToken) $2;
5819                 var li = new LocalVariable (current_variable.Variable, lt.Value, lt.Location);
5820                 var d = new BlockVariableDeclarator (li, null);
5821                 current_variable.AddDeclarator (d);
5822                 current_block.AddLocalName (li);
5823                 lbag.AddLocation (d, GetLocation ($1));
5824           }
5825         | COMMA identifier_inside_body ASSIGN block_variable_initializer
5826           {
5827                 var lt = (LocatedToken) $2;
5828                 var li = new LocalVariable (current_variable.Variable, lt.Value, lt.Location);
5829                 var d = new BlockVariableDeclarator (li, (Expression) $4);
5830                 current_variable.AddDeclarator (d);
5831                 current_block.AddLocalName (li);
5832                 lbag.AddLocation (d, GetLocation ($1), GetLocation ($3));
5833           }
5834         ;
5835
5836 const_variable_initializer
5837         : /* empty */
5838           {
5839                 report.Error (145, lexer.Location, "A const field requires a value to be provided");
5840           }
5841         | ASSIGN constant_initializer_expr
5842           {
5843                 current_variable.Initializer = (Expression) $2;
5844           }
5845         ;
5846
5847 opt_const_declarators
5848         : /* empty */
5849         | const_declarators
5850         ;
5851
5852 const_declarators
5853         : const_declarator
5854         | const_declarators const_declarator
5855         ;
5856
5857 const_declarator
5858         : COMMA identifier_inside_body ASSIGN constant_initializer_expr
5859           {
5860                 var lt = (LocatedToken) $2;
5861                 var li = new LocalVariable (current_block, lt.Value, LocalVariable.Flags.Constant, lt.Location);
5862                 var d = new BlockVariableDeclarator (li, (Expression) $4);
5863                 current_variable.AddDeclarator (d);
5864                 current_block.AddLocalName (li);
5865                 lbag.AddLocation (d, GetLocation ($1), GetLocation ($3));
5866           }
5867         ;
5868
5869 block_variable_initializer
5870         : variable_initializer
5871         | STACKALLOC simple_type OPEN_BRACKET_EXPR expression CLOSE_BRACKET
5872           {
5873                 $$ = new StackAlloc ((Expression) $2, (Expression) $4, GetLocation ($1));
5874                 lbag.AddLocation ($$, GetLocation ($3), GetLocation ($5));
5875           }
5876         | STACKALLOC simple_type
5877           {
5878                 report.Error (1575, GetLocation ($1), "A stackalloc expression requires [] after type");
5879                 $$ = new StackAlloc ((Expression) $2, null, GetLocation ($1));
5880           }
5881         ;
5882
5883 expression_statement
5884         : statement_expression SEMICOLON
5885           {
5886                 $$ = $1;
5887                 lbag.AddStatement ($$, GetLocation ($2));
5888           }
5889         | statement_expression COMPLETE_COMPLETION { $$ = $1; }
5890         | statement_expression CLOSE_BRACE
5891           {
5892                 $$ = $1;
5893                 report.Error (1002, GetLocation ($2), "; expected");
5894                 lexer.putback ('}');
5895           }
5896         ;
5897
5898 interactive_expression_statement
5899         : interactive_statement_expression SEMICOLON { $$ = $1; }
5900         | interactive_statement_expression COMPLETE_COMPLETION { $$ = $1; }
5901         ;
5902
5903         //
5904         // We have to do the wrapping here and not in the case above,
5905         // because statement_expression is used for example in for_statement
5906         //
5907 statement_expression
5908         : expression
5909           {
5910                 ExpressionStatement s = $1 as ExpressionStatement;
5911                 if (s == null) {
5912                         var expr = $1 as Expression;
5913                         $$ = new StatementErrorExpression (expr);
5914                 } else {
5915                         $$ = new StatementExpression (s);
5916                 }
5917           }
5918         ;
5919
5920 interactive_statement_expression
5921         : expression
5922           {
5923                 Expression expr = (Expression) $1;
5924                 $$ = new StatementExpression (new OptionalAssign (expr, lexer.Location));
5925           }
5926         | error
5927           {
5928                 Error_SyntaxError (yyToken);
5929                 $$ = new EmptyStatement (GetLocation ($1));
5930           }
5931         ;
5932
5933 selection_statement
5934         : if_statement
5935         | switch_statement
5936         ;
5937
5938 if_statement
5939         : IF open_parens_any boolean_expression CLOSE_PARENS
5940           embedded_statement
5941           {
5942                 if ($5 is EmptyStatement)
5943                         Warning_EmptyStatement (GetLocation ($5));
5944
5945                 $$ = new If ((BooleanExpression) $3, (Statement) $5, GetLocation ($1));
5946                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($4));
5947           }
5948         | IF open_parens_any boolean_expression CLOSE_PARENS
5949           embedded_statement ELSE embedded_statement
5950           {
5951                 $$ = new If ((BooleanExpression) $3, (Statement) $5, (Statement) $7, GetLocation ($1));
5952                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($4), GetLocation ($6));
5953
5954                 if ($5 is EmptyStatement)
5955                         Warning_EmptyStatement (GetLocation ($5));
5956                 if ($7 is EmptyStatement)
5957                         Warning_EmptyStatement (GetLocation ($7));
5958           }
5959         | IF open_parens_any boolean_expression error
5960           {
5961                 Error_SyntaxError (yyToken);
5962
5963                 $$ = new If ((BooleanExpression) $3, null, GetLocation ($1));
5964                 lbag.AddStatement ($$, GetLocation ($2));
5965           }
5966         ;
5967
5968 switch_statement
5969         : SWITCH open_parens_any expression CLOSE_PARENS OPEN_BRACE
5970           {
5971                 start_block (GetLocation ($5));
5972           }
5973           opt_switch_sections CLOSE_BRACE
5974           {
5975                 $$ = new Switch ((Expression) $3, (ExplicitBlock) current_block.Explicit, GetLocation ($1));
5976                 end_block (GetLocation ($8));
5977                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($4));
5978           }
5979         | SWITCH open_parens_any expression error
5980           {
5981                 Error_SyntaxError (yyToken);
5982
5983                 $$ = new Switch ((Expression) $3, null, GetLocation ($1));
5984                 lbag.AddStatement ($$, GetLocation ($2));
5985           }
5986         ;
5987
5988 opt_switch_sections
5989         : /* empty */
5990       {
5991                 report.Warning (1522, 1, current_block.StartLocation, "Empty switch block");
5992           }
5993         | switch_sections
5994         ;
5995
5996 switch_sections
5997         : switch_section
5998         | switch_sections switch_section
5999         | error
6000           {
6001                 Error_SyntaxError (yyToken);
6002           }
6003         ;
6004
6005 switch_section
6006         : switch_labels statement_list
6007         ;
6008
6009 switch_labels
6010         : switch_label
6011           {
6012                 var label = (SwitchLabel) $1;
6013                 label.SectionStart = true;
6014                 current_block.AddStatement (label);
6015           }
6016         | switch_labels switch_label
6017           {
6018                 current_block.AddStatement ((Statement) $2);
6019           }
6020         ;
6021
6022 switch_label
6023         : CASE constant_expression COLON
6024          {
6025                 $$ = new SwitchLabel ((Expression) $2, GetLocation ($1));
6026                 lbag.AddLocation ($$, GetLocation ($3));
6027          }
6028         | CASE constant_expression error
6029           {
6030                 Error_SyntaxError (yyToken);
6031                 $$ = new SwitchLabel ((Expression) $2, GetLocation ($1));
6032           }
6033 /*
6034         | CASE pattern_expr_invocation COLON
6035           {
6036                 if (lang_version != LanguageVersion.Experimental)
6037                         FeatureIsNotAvailable (GetLocation ($2), "pattern matching");
6038
6039                 $$ = new SwitchLabel ((Expression) $2, GetLocation ($1)) {
6040                         PatternMatching = true
6041                 };
6042                 lbag.AddLocation ($$, GetLocation ($3));
6043           }
6044 */
6045         | DEFAULT_COLON
6046           {
6047                 $$ = new SwitchLabel (null, GetLocation ($1));
6048           }
6049         ;
6050
6051 iteration_statement
6052         : while_statement
6053         | do_statement
6054         | for_statement
6055         | foreach_statement
6056         ;
6057
6058 while_statement
6059         : WHILE open_parens_any boolean_expression CLOSE_PARENS embedded_statement
6060           {
6061                 if ($5 is EmptyStatement && lexer.peek_token () == Token.OPEN_BRACE)
6062                         Warning_EmptyStatement (GetLocation ($5));
6063
6064                 $$ = new While ((BooleanExpression) $3, (Statement) $5, GetLocation ($1));
6065                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($4));
6066           }
6067         | WHILE open_parens_any boolean_expression error
6068           {
6069                 Error_SyntaxError (yyToken);
6070
6071                 $$ = new While ((BooleanExpression) $3, null, GetLocation ($1));
6072                 lbag.AddStatement ($$, GetLocation ($2));
6073           }
6074         ;
6075
6076 do_statement
6077         : DO embedded_statement WHILE open_parens_any boolean_expression CLOSE_PARENS SEMICOLON
6078           {
6079                 $$ = new Do ((Statement) $2, (BooleanExpression) $5, GetLocation ($1), GetLocation ($3));
6080                 lbag.AddStatement ($$, GetLocation ($3), GetLocation ($4), GetLocation ($6), GetLocation ($7));
6081           }
6082         | DO embedded_statement error
6083           {
6084                 Error_SyntaxError (yyToken);
6085                 $$ = new Do ((Statement) $2, null, GetLocation ($1), Location.Null);
6086           }
6087         | DO embedded_statement WHILE open_parens_any boolean_expression error
6088           {
6089                 Error_SyntaxError (yyToken);
6090
6091                 $$ = new Do ((Statement) $2, (BooleanExpression) $5, GetLocation ($1), GetLocation ($3));
6092                 lbag.AddStatement ($$, GetLocation ($3), GetLocation ($4));
6093           }
6094         ;
6095
6096 for_statement
6097         : FOR open_parens_any
6098           {
6099                 start_block (GetLocation ($2));
6100                 current_block.IsCompilerGenerated = true;
6101                 For f = new For (GetLocation ($1));
6102                 current_block.AddStatement (f);
6103                 $$ = f;
6104           }
6105           for_statement_cont
6106           {
6107                 $$ = $4;
6108           }
6109         ;
6110
6111 // Has to use be extra rule to recover started block
6112 for_statement_cont
6113         : opt_for_initializer SEMICOLON
6114           {
6115                 ((For) $0).Initializer = (Statement) $1;
6116
6117                 // Pass the "For" object to the iterator_part4
6118                 oob_stack.Push ($0);
6119           }
6120           for_condition_and_iterator_part
6121           embedded_statement
6122           {
6123                 var locations = (Tuple<Location,Location>) $4;
6124                 oob_stack.Pop ();
6125                 if ($5 is EmptyStatement && lexer.peek_token () == Token.OPEN_BRACE)
6126                         Warning_EmptyStatement (GetLocation ($5));
6127
6128                 For f = ((For) $0);
6129                 f.Statement = (Statement) $5;
6130                 lbag.AddStatement (f, current_block.StartLocation, GetLocation ($2), GetLocation (locations.Item1), GetLocation (locations.Item2));
6131
6132                 $$ = end_block (GetLocation ($2));
6133           }
6134         | error
6135           {
6136                 Error_SyntaxError (yyToken);
6137                 $$ = end_block (current_block.StartLocation);
6138           }
6139         ;
6140
6141 for_condition_and_iterator_part
6142         : opt_for_condition SEMICOLON
6143           {
6144                 For f = (For) oob_stack.Peek ();
6145                 f.Condition = (BooleanExpression) $1;
6146           }
6147           for_iterator_part {
6148                 $$ = new Tuple<Location,Location> (GetLocation ($2), (Location) $4);
6149           }
6150
6151         // Handle errors in the case of opt_for_condition being followed by
6152         // a close parenthesis
6153         | opt_for_condition close_parens_close_brace {
6154                 report.Error (1525, GetLocation ($2), "Unexpected symbol `}'");
6155                 For f = (For) oob_stack.Peek ();
6156                 f.Condition = (BooleanExpression) $1;
6157                 $$ = new Tuple<Location,Location> (GetLocation ($2), GetLocation ($2));
6158           }
6159         ;
6160
6161 for_iterator_part
6162         : opt_for_iterator CLOSE_PARENS {
6163                 For f = (For) oob_stack.Peek ();
6164                 f.Iterator = (Statement) $1;
6165                 $$ = GetLocation ($2);
6166           }
6167         | opt_for_iterator CLOSE_BRACE {
6168                 report.Error (1525, GetLocation ($2), "Unexpected symbol expected ')'");
6169                 For f = (For) oob_stack.Peek ();
6170                 f.Iterator = (Statement) $1;
6171                 $$ = GetLocation ($2);
6172           }
6173         ;
6174
6175 close_parens_close_brace
6176         : CLOSE_PARENS
6177         | CLOSE_BRACE { lexer.putback ('}'); }
6178         ;
6179
6180 opt_for_initializer
6181         : /* empty */           { $$ = new EmptyStatement (lexer.Location); }
6182         | for_initializer
6183         ;
6184
6185 for_initializer
6186         : variable_type identifier_inside_body
6187           {
6188                 var lt = (LocatedToken) $2;
6189                 var li = new LocalVariable (current_block, lt.Value, lt.Location);
6190                 current_block.AddLocalName (li);
6191                 current_variable = new BlockVariable ((FullNamedExpression) $1, li);
6192           }
6193           opt_local_variable_initializer opt_variable_declarators
6194           {
6195                 $$ = current_variable;
6196                 if ($4 != null)
6197                         lbag.AddLocation (current_variable, PopLocation ());
6198
6199                 current_variable = null;
6200           }
6201         | statement_expression_list
6202         ;
6203
6204 opt_for_condition
6205         : /* empty */           { $$ = null; }
6206         | boolean_expression
6207         ;
6208
6209 opt_for_iterator
6210         : /* empty */           { $$ = new EmptyStatement (lexer.Location); }
6211         | for_iterator
6212         ;
6213
6214 for_iterator
6215         : statement_expression_list
6216         ;
6217
6218 statement_expression_list
6219         : statement_expression
6220         | statement_expression_list COMMA statement_expression
6221           {
6222                 var sl = $1 as StatementList;
6223                 if (sl == null) {
6224                         sl = new StatementList ((Statement) $1, (Statement) $3);
6225                         lbag.AddStatement (sl, GetLocation ($2));
6226                 } else {
6227                         sl.Add ((Statement) $3);
6228                         lbag.AppendTo (sl, GetLocation ($2));
6229                 }
6230
6231                 $$ = sl;
6232           }
6233         ;
6234
6235 foreach_statement
6236         : FOREACH open_parens_any type error
6237           {
6238                 report.Error (230, GetLocation ($1), "Type and identifier are both required in a foreach statement");
6239
6240                 start_block (GetLocation ($2));
6241                 current_block.IsCompilerGenerated = true;
6242
6243                 Foreach f = new Foreach ((Expression) $3, null, null, null, null, GetLocation ($1));
6244                 current_block.AddStatement (f);
6245
6246                 lbag.AddStatement (f, GetLocation ($2));
6247                 $$ = end_block (GetLocation ($4));
6248           }
6249         | FOREACH open_parens_any type identifier_inside_body error
6250           {
6251                 Error_SyntaxError (yyToken);
6252
6253                 start_block (GetLocation ($2));
6254                 current_block.IsCompilerGenerated = true;
6255
6256                 var lt = (LocatedToken) $4;
6257                 var li = new LocalVariable (current_block, lt.Value, LocalVariable.Flags.ForeachVariable | LocalVariable.Flags.Used, lt.Location);
6258                 current_block.AddLocalName (li);
6259
6260                 Foreach f = new Foreach ((Expression) $3, li, null, null, null, GetLocation ($1));
6261                 current_block.AddStatement (f);
6262
6263                 lbag.AddStatement (f, GetLocation ($2));
6264                 $$ = end_block (GetLocation ($5));
6265           }
6266         | FOREACH open_parens_any type identifier_inside_body IN expression CLOSE_PARENS
6267           {
6268                 start_block (GetLocation ($2));
6269                 current_block.IsCompilerGenerated = true;
6270
6271                 var lt = (LocatedToken) $4;
6272                 var li = new LocalVariable (current_block, lt.Value, LocalVariable.Flags.ForeachVariable | LocalVariable.Flags.Used, lt.Location);
6273                 current_block.AddLocalName (li);
6274                 $$ = li;
6275           }
6276           embedded_statement
6277           {
6278                 if ($9 is EmptyStatement && lexer.peek_token () == Token.OPEN_BRACE)
6279                         Warning_EmptyStatement (GetLocation ($9));
6280
6281                 Foreach f = new Foreach ((Expression) $3, (LocalVariable) $8, (Expression) $6, (Statement) $9, current_block, GetLocation ($1));
6282                 lbag.AddStatement (f, GetLocation ($2), GetLocation ($5), GetLocation ($7));
6283                 end_block (GetLocation ($7));
6284
6285                 $$ = f;
6286           }
6287         ;
6288
6289 jump_statement
6290         : break_statement
6291         | continue_statement
6292         | goto_statement
6293         | return_statement
6294         | throw_statement
6295         | yield_statement
6296         ;
6297
6298 break_statement
6299         : BREAK SEMICOLON
6300           {
6301                 $$ = new Break (GetLocation ($1));
6302                 lbag.AddStatement ($$, GetLocation ($2));
6303           }
6304         ;
6305
6306 continue_statement
6307         : CONTINUE SEMICOLON
6308           {
6309                 $$ = new Continue (GetLocation ($1));
6310                 lbag.AddStatement ($$, GetLocation ($2));
6311           }
6312         | CONTINUE error
6313           {
6314                 Error_SyntaxError (yyToken);
6315                 $$ = new Continue (GetLocation ($1));
6316           }
6317         ;
6318
6319 goto_statement
6320         : GOTO identifier_inside_body SEMICOLON
6321           {
6322                 var lt = (LocatedToken) $2;
6323                 $$ = new Goto (lt.Value, GetLocation ($1));
6324                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($3));
6325           }
6326         | GOTO CASE constant_expression SEMICOLON
6327           {
6328                 $$ = new GotoCase ((Expression) $3, GetLocation ($1));
6329                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($4));
6330           }
6331         | GOTO DEFAULT SEMICOLON
6332           {
6333                 $$ = new GotoDefault (GetLocation ($1));
6334                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($3));
6335           }
6336         ;
6337
6338 return_statement
6339         : RETURN opt_expression SEMICOLON
6340           {
6341                 $$ = new Return ((Expression) $2, GetLocation ($1));
6342                 lbag.AddStatement ($$, GetLocation ($3));
6343           }
6344         | RETURN expression error
6345           {
6346                 Error_SyntaxError (yyToken);
6347                 $$ = new Return ((Expression) $2, GetLocation ($1));
6348           }
6349         | RETURN error
6350           {
6351                 Error_SyntaxError (yyToken);
6352                 $$ = new Return (null, GetLocation ($1));
6353           }
6354         ;
6355
6356 throw_statement
6357         : THROW opt_expression SEMICOLON
6358           {
6359                 $$ = new Throw ((Expression) $2, GetLocation ($1));
6360                 lbag.AddStatement ($$, GetLocation ($3));
6361           }
6362         | THROW expression error
6363           {
6364                 Error_SyntaxError (yyToken);
6365                 $$ = new Throw ((Expression) $2, GetLocation ($1));
6366           }
6367         | THROW error
6368           {
6369                 Error_SyntaxError (yyToken);
6370                 $$ = new Throw (null, GetLocation ($1));
6371           }
6372         ;
6373
6374 yield_statement
6375         : identifier_inside_body RETURN opt_expression SEMICOLON
6376           {
6377                 var lt = (LocatedToken) $1;
6378                 string s = lt.Value;
6379                 if (s != "yield"){
6380                         report.Error (1003, lt.Location, "; expected");
6381                 } else if ($3 == null) {
6382                         report.Error (1627, GetLocation ($4), "Expression expected after yield return");
6383                 } else if (lang_version == LanguageVersion.ISO_1){
6384                         FeatureIsNotAvailable (lt.Location, "iterators");
6385                 }
6386
6387                 current_block.Explicit.RegisterIteratorYield ();
6388                 $$ = new Yield ((Expression) $3, lt.Location);
6389                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($4));
6390           }
6391         | identifier_inside_body RETURN expression error
6392           {
6393                 Error_SyntaxError (yyToken);
6394
6395                 var lt = (LocatedToken) $1;
6396                 string s = lt.Value;
6397                 if (s != "yield"){
6398                         report.Error (1003, lt.Location, "; expected");
6399                 } else if ($3 == null) {
6400                         report.Error (1627, GetLocation ($4), "Expression expected after yield return");
6401                 } else if (lang_version == LanguageVersion.ISO_1){
6402                         FeatureIsNotAvailable (lt.Location, "iterators");
6403                 }
6404
6405                 current_block.Explicit.RegisterIteratorYield ();
6406                 $$ = new Yield ((Expression) $3, lt.Location);
6407                 lbag.AddStatement ($$, GetLocation ($2));
6408           }
6409         | identifier_inside_body BREAK SEMICOLON
6410           {
6411                 var lt = (LocatedToken) $1;
6412                 string s = lt.Value;
6413                 if (s != "yield"){
6414                         report.Error (1003, lt.Location, "; expected");
6415                 } else if (lang_version == LanguageVersion.ISO_1){
6416                         FeatureIsNotAvailable (lt.Location, "iterators");
6417                 }
6418
6419                 current_block.ParametersBlock.TopBlock.IsIterator = true;
6420                 $$ = new YieldBreak (lt.Location);
6421                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($3));
6422           }
6423         ;
6424
6425 opt_expression
6426         : /* empty */
6427         | expression
6428         ;
6429
6430 try_statement
6431         : TRY block catch_clauses
6432           {
6433                 $$ = new TryCatch ((Block) $2, (List<Catch>) $3, GetLocation ($1), false);
6434           }
6435         | TRY block FINALLY block
6436           {
6437                 $$ = new TryFinally ((Statement) $2, (ExplicitBlock) $4, GetLocation ($1));
6438                 lbag.AddStatement ($$, GetLocation ($3));
6439           }
6440         | TRY block catch_clauses FINALLY block
6441           {
6442                 $$ = new TryFinally (new TryCatch ((Block) $2, (List<Catch>) $3, Location.Null, true), (ExplicitBlock) $5, GetLocation ($1));
6443                 lbag.AddStatement ($$, GetLocation ($4));
6444           }
6445         | TRY block error
6446           {
6447                 Error_SyntaxError (1524, yyToken);
6448                 $$ = new TryCatch ((Block) $2, null, GetLocation ($1), false);
6449           }
6450         ;
6451
6452 catch_clauses
6453         : catch_clause
6454           {
6455                 var l = new List<Catch> (2);
6456
6457                 l.Add ((Catch) $1);
6458                 $$ = l;
6459           }
6460         | catch_clauses catch_clause
6461           {
6462                 var l = (List<Catch>) $1;
6463
6464                 Catch c = (Catch) $2;
6465                 var prev_catch = l [l.Count - 1];
6466                 if (prev_catch.IsGeneral && prev_catch.Filter == null) {
6467                         report.Error (1017, c.loc, "Try statement already has an empty catch block");
6468                 }
6469
6470                 l.Add (c);
6471                 $$ = l;
6472           }
6473         ;
6474
6475 opt_identifier
6476         : /* empty */
6477         | identifier_inside_body
6478         ;
6479
6480 catch_clause
6481         : CATCH opt_catch_filter block
6482           {
6483                 var c = new Catch ((ExplicitBlock) $3, GetLocation ($1));
6484                 c.Filter = (CatchFilterExpression) $2;
6485                 $$ = c;
6486           }
6487         | CATCH open_parens_any type opt_identifier CLOSE_PARENS
6488           {
6489                 start_block (GetLocation ($2));
6490                 var c = new Catch ((ExplicitBlock) current_block, GetLocation ($1));
6491                 c.TypeExpression = (FullNamedExpression) $3;
6492
6493                 if ($4 != null) {
6494                         var lt = (LocatedToken) $4;
6495                         c.Variable = new LocalVariable (current_block, lt.Value, lt.Location);
6496                         current_block.AddLocalName (c.Variable);
6497                 }
6498
6499                 lbag.AddLocation (c, GetLocation ($2), GetLocation ($5));
6500                 $$ = c;
6501                 lexer.parsing_catch_when = true;
6502           }
6503           opt_catch_filter_or_error
6504           {
6505                 ((Catch) $6).Filter = (CatchFilterExpression) $7;
6506                 $$ = $6;
6507           }
6508         | CATCH open_parens_any error
6509           {
6510                 if (yyToken == Token.CLOSE_PARENS) {
6511                         report.Error (1015, lexer.Location,
6512                                 "A type that derives from `System.Exception', `object', or `string' expected");
6513                 } else {
6514                         Error_SyntaxError (yyToken);
6515                 }
6516
6517                 $$ = new Catch (null, GetLocation ($1));
6518           }
6519         ;
6520
6521 opt_catch_filter_or_error
6522         : opt_catch_filter block_prepared
6523           {
6524                 $$ = $1;
6525           }
6526         | error
6527           {
6528                 end_block (Location.Null);
6529                 Error_SyntaxError (yyToken);
6530                 $$ = null;
6531           }
6532         ;
6533
6534 opt_catch_filter
6535         : {
6536                 lexer.parsing_catch_when = false;
6537           }
6538         | WHEN
6539           {
6540                 lexer.parsing_catch_when = false;
6541           }
6542           open_parens_any expression CLOSE_PARENS
6543           {
6544                 if (lang_version <= LanguageVersion.V_5)
6545                         FeatureIsNotAvailable (GetLocation ($1), "exception filter");
6546
6547                 $$ = new CatchFilterExpression ((Expression) $4, GetLocation ($1));
6548                 lbag.AddLocation ($$, GetLocation ($3), GetLocation ($5));
6549           }
6550         ;
6551
6552 checked_statement
6553         : CHECKED block
6554           {
6555                 $$ = new Checked ((Block) $2, GetLocation ($1));
6556           }
6557         ;
6558
6559 unchecked_statement
6560         : UNCHECKED block
6561           {
6562                 $$ = new Unchecked ((Block) $2, GetLocation ($1));
6563           }
6564         ;
6565
6566 unsafe_statement
6567         : UNSAFE
6568           {
6569                 if (!settings.Unsafe)
6570                         Error_UnsafeCodeNotAllowed (GetLocation ($1));
6571           } block {
6572                 $$ = new Unsafe ((Block) $3, GetLocation ($1));
6573           }
6574         ;
6575
6576 lock_statement
6577         : LOCK open_parens_any expression CLOSE_PARENS embedded_statement
6578           {
6579                 if ($5 is EmptyStatement && lexer.peek_token () == Token.OPEN_BRACE)
6580                         Warning_EmptyStatement (GetLocation ($5));
6581
6582                 $$ = new Lock ((Expression) $3, (Statement) $5, GetLocation ($1));
6583                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($4));
6584           }
6585         | LOCK open_parens_any expression error
6586           {
6587                 Error_SyntaxError (yyToken);
6588
6589                 $$ = new Lock ((Expression) $3, null, GetLocation ($1));
6590                 lbag.AddStatement ($$, GetLocation ($2));
6591           }
6592         ;
6593
6594 fixed_statement
6595         : FIXED open_parens_any variable_type identifier_inside_body
6596           {
6597             start_block (GetLocation ($2));
6598
6599                 current_block.IsCompilerGenerated = true;
6600                 var lt = (LocatedToken) $4;
6601                 var li = new LocalVariable (current_block, lt.Value, LocalVariable.Flags.FixedVariable | LocalVariable.Flags.Used, lt.Location);
6602                 current_block.AddLocalName (li);
6603                 current_variable = new Fixed.VariableDeclaration ((FullNamedExpression) $3, li);
6604           }
6605           using_or_fixed_variable_initializer opt_using_or_fixed_variable_declarators CLOSE_PARENS
6606           {
6607                 $$ = current_variable;
6608                 current_variable = null;
6609           }
6610           embedded_statement
6611           {
6612                 if ($10 is EmptyStatement && lexer.peek_token () == Token.OPEN_BRACE)
6613                         Warning_EmptyStatement (GetLocation ($10));
6614
6615                 Fixed f = new Fixed ((Fixed.VariableDeclaration) $9, (Statement) $10, GetLocation ($1));
6616                 current_block.AddStatement (f);
6617                 lbag.AddStatement (f, GetLocation ($2), GetLocation ($8));
6618                 $$ = end_block (GetLocation ($8));
6619           }
6620         ;
6621
6622 using_statement
6623         : USING open_parens_any variable_type identifier_inside_body
6624           {
6625             start_block (GetLocation ($2));
6626
6627                 current_block.IsCompilerGenerated = true;
6628                 var lt = (LocatedToken) $4;
6629                 var li = new LocalVariable (current_block, lt.Value, LocalVariable.Flags.UsingVariable | LocalVariable.Flags.Used, lt.Location);
6630                 current_block.AddLocalName (li);
6631                 current_variable = new Using.VariableDeclaration ((FullNamedExpression) $3, li);
6632           }
6633           using_initialization CLOSE_PARENS
6634           {
6635                 $$ = current_variable;
6636                 current_variable = null;
6637           }
6638           embedded_statement
6639           {
6640                 if ($9 is EmptyStatement && lexer.peek_token () == Token.OPEN_BRACE)
6641                         Warning_EmptyStatement (GetLocation ($9));
6642
6643                 Using u = new Using ((Using.VariableDeclaration) $8, (Statement) $9, GetLocation ($1));
6644                 current_block.AddStatement (u);
6645                 $$ = end_block (GetLocation ($7));
6646           }
6647         | USING open_parens_any expression CLOSE_PARENS embedded_statement
6648           {
6649                 if ($5 is EmptyStatement && lexer.peek_token () == Token.OPEN_BRACE)
6650                         Warning_EmptyStatement (GetLocation ($5));
6651
6652                 $$ = new Using ((Expression) $3, (Statement) $5, GetLocation ($1));
6653                 lbag.AddStatement ($$, GetLocation ($2), GetLocation ($4));
6654           }
6655         | USING open_parens_any expression error
6656           {
6657                 Error_SyntaxError (yyToken);
6658
6659                 $$ = new Using ((Expression) $3, null, GetLocation ($1));
6660                 lbag.AddStatement ($$, GetLocation ($2));
6661           }
6662         ;
6663
6664 using_initialization
6665         : using_or_fixed_variable_initializer opt_using_or_fixed_variable_declarators
6666         | error
6667           {
6668                 // It has to be here for the parent to safely restore artificial block
6669                 Error_SyntaxError (yyToken);
6670           }
6671         ;
6672
6673 using_or_fixed_variable_initializer
6674         : /* empty */
6675           {
6676                 Error_MissingInitializer (lexer.Location);
6677           }
6678         | ASSIGN variable_initializer
6679           {
6680                 current_variable.Initializer = (Expression) $2;
6681                 $$ = current_variable;
6682           }
6683         ;
6684
6685
6686 // LINQ
6687
6688 query_expression
6689         : first_from_clause query_body
6690           {
6691                 lexer.query_parsing = false;
6692
6693                 Linq.AQueryClause from = $1 as Linq.AQueryClause;
6694
6695                 from.Tail.Next = (Linq.AQueryClause)$2;
6696                 $$ = from;
6697
6698                 current_block.SetEndLocation (lexer.Location);
6699                 current_block = current_block.Parent;
6700           }
6701         | nested_from_clause query_body
6702           {
6703                 Linq.AQueryClause from = $1 as Linq.AQueryClause;
6704
6705                 from.Tail.Next = (Linq.AQueryClause)$2;
6706                 $$ = from;
6707
6708                 current_block.SetEndLocation (lexer.Location);
6709                 current_block = current_block.Parent;
6710           }
6711
6712         // Bubble up COMPLETE_COMPLETION productions
6713         | first_from_clause COMPLETE_COMPLETION {
6714                 lexer.query_parsing = false;
6715                 $$ = $1;
6716
6717                 current_block.SetEndLocation (lexer.Location);
6718                 current_block = current_block.Parent;
6719           }
6720         | nested_from_clause COMPLETE_COMPLETION {
6721                 $$ = $1;
6722                 current_block.SetEndLocation (lexer.Location);
6723                 current_block = current_block.Parent;
6724           }
6725         ;
6726
6727 first_from_clause
6728         : FROM_FIRST identifier_inside_body IN expression
6729           {
6730                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6731
6732                 var lt = (LocatedToken) $2;
6733                 var rv = new Linq.RangeVariable (lt.Value, lt.Location);
6734                 var clause = new Linq.QueryStartClause ((Linq.QueryBlock)current_block, (Expression)$4, rv, GetLocation ($1));
6735                 lbag.AddLocation (clause, GetLocation ($3));
6736                 $$ = new Linq.QueryExpression (clause);
6737           }
6738         | FROM_FIRST type identifier_inside_body IN expression
6739           {
6740                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6741
6742                 var lt = (LocatedToken) $3;
6743                 var rv = new Linq.RangeVariable (lt.Value, lt.Location);
6744                 var clause = new Linq.QueryStartClause ((Linq.QueryBlock)current_block, (Expression)$5, rv, GetLocation ($1)) {
6745                                 IdentifierType = (FullNamedExpression)$2
6746                 };
6747                 lbag.AddLocation (clause, GetLocation ($4));
6748                 $$ = new Linq.QueryExpression (clause);
6749           }
6750         ;
6751
6752 nested_from_clause
6753         : FROM identifier_inside_body IN expression
6754           {
6755                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6756
6757                 var lt = (LocatedToken) $2;
6758                 var rv = new Linq.RangeVariable (lt.Value, lt.Location);
6759                 var clause = new Linq.QueryStartClause ((Linq.QueryBlock)current_block, (Expression)$4, rv, GetLocation ($1));
6760                 lbag.AddLocation (clause, GetLocation ($3));
6761                 $$ = new Linq.QueryExpression (clause);
6762           }
6763         | FROM type identifier_inside_body IN expression
6764           {
6765                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6766
6767                 var lt = (LocatedToken) $3;
6768                 var rv = new Linq.RangeVariable (lt.Value, lt.Location);
6769                 var clause = new Linq.QueryStartClause ((Linq.QueryBlock)current_block, (Expression)$5, rv, GetLocation ($1)) {
6770                                 IdentifierType = (FullNamedExpression)$2
6771                 };
6772                 lbag.AddLocation (clause, GetLocation ($4));
6773                 $$ = new Linq.QueryExpression (clause);
6774           }
6775         ;
6776
6777 from_clause
6778         : FROM identifier_inside_body IN
6779           {
6780                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6781           }
6782           expression_or_error
6783           {
6784                 var lt = (LocatedToken) $2;
6785                 var sn = new Linq.RangeVariable (lt.Value, lt.Location);
6786                 $$ = new Linq.SelectMany ((Linq.QueryBlock)current_block, sn, (Expression)$5, GetLocation ($1));
6787
6788                 current_block.SetEndLocation (lexer.Location);
6789                 current_block = current_block.Parent;
6790
6791                 ((Linq.QueryBlock)current_block).AddRangeVariable (sn);
6792                 lbag.AddLocation ($$, GetLocation ($3));
6793           }
6794         | FROM type identifier_inside_body IN
6795           {
6796                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6797           }
6798           expression_or_error
6799           {
6800                 var lt = (LocatedToken) $3;
6801                 var sn = new Linq.RangeVariable (lt.Value, lt.Location);
6802
6803                 $$ = new Linq.SelectMany ((Linq.QueryBlock)current_block, sn, (Expression)$6, GetLocation ($1)) {
6804                         IdentifierType = (FullNamedExpression)$2
6805                 };
6806
6807                 current_block.SetEndLocation (lexer.Location);
6808                 current_block = current_block.Parent;
6809
6810                 ((Linq.QueryBlock)current_block).AddRangeVariable (sn);
6811
6812                 lbag.AddLocation ($$, GetLocation ($4));
6813           }
6814         ;
6815
6816 query_body
6817         : query_body_clauses select_or_group_clause opt_query_continuation
6818           {
6819                 Linq.AQueryClause head = (Linq.AQueryClause)$2;
6820
6821                 if ($3 != null)
6822                         head.Next = (Linq.AQueryClause)$3;
6823
6824                 if ($1 != null) {
6825                         Linq.AQueryClause clause = (Linq.AQueryClause)$1;
6826                         clause.Tail.Next = head;
6827                         head = clause;
6828                 }
6829
6830                 $$ = head;
6831           }
6832         | select_or_group_clause opt_query_continuation
6833           {
6834                 Linq.AQueryClause head = (Linq.AQueryClause)$2;
6835
6836                 if ($1 != null) {
6837                         Linq.AQueryClause clause = (Linq.AQueryClause)$1;
6838                         clause.Tail.Next = head;
6839                         head = clause;
6840                 }
6841
6842                 $$ = head;
6843           }
6844         | query_body_clauses COMPLETE_COMPLETION
6845         | query_body_clauses error
6846           {
6847                 report.Error (742, GetLocation ($2), "Unexpected symbol `{0}'. A query body must end with select or group clause", GetSymbolName (yyToken));
6848                 $$ = $1;
6849           }
6850         | error
6851           {
6852                 Error_SyntaxError (yyToken);
6853                 $$ = null;
6854           }
6855         ;
6856
6857 select_or_group_clause
6858         : SELECT
6859           {
6860                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6861           }
6862           expression_or_error
6863           {
6864                 $$ = new Linq.Select ((Linq.QueryBlock)current_block, (Expression)$3, GetLocation ($1));
6865
6866                 current_block.SetEndLocation (lexer.Location);
6867                 current_block = current_block.Parent;
6868           }
6869         | GROUP
6870           {
6871                 if (linq_clause_blocks == null)
6872                         linq_clause_blocks = new Stack<Linq.QueryBlock> ();
6873
6874                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6875                 linq_clause_blocks.Push ((Linq.QueryBlock)current_block);
6876           }
6877           expression_or_error
6878           {
6879                 current_block.SetEndLocation (lexer.Location);
6880                 current_block = current_block.Parent;
6881
6882                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6883           }
6884           by_expression
6885           {
6886                 var obj = (object[]) $5;
6887
6888                 $$ = new Linq.GroupBy ((Linq.QueryBlock)current_block, (Expression)$3, linq_clause_blocks.Pop (), (Expression)obj[0], GetLocation ($1));
6889                 lbag.AddLocation ($$, (Location) obj[1]);
6890
6891                 current_block.SetEndLocation (lexer.Location);
6892                 current_block = current_block.Parent;
6893           }
6894         ;
6895
6896 by_expression
6897         : BY expression_or_error
6898           {
6899                 $$ = new object[] { $2, GetLocation ($1) };
6900           }
6901         | error
6902           {
6903                 Error_SyntaxError (yyToken);
6904                 $$ = new object[2] { null, Location.Null };
6905           }
6906         ;
6907
6908 query_body_clauses
6909         : query_body_clause
6910         | query_body_clauses query_body_clause
6911           {
6912                 ((Linq.AQueryClause)$1).Tail.Next = (Linq.AQueryClause)$2;
6913                 $$ = $1;
6914           }
6915         ;
6916
6917 query_body_clause
6918         : from_clause
6919         | let_clause
6920         | where_clause
6921         | join_clause
6922         | orderby_clause
6923         ;
6924
6925 let_clause
6926         : LET identifier_inside_body ASSIGN
6927           {
6928                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6929           }
6930           expression_or_error
6931           {
6932                 var lt = (LocatedToken) $2;
6933                 var sn = new Linq.RangeVariable (lt.Value, lt.Location);
6934                 $$ = new Linq.Let ((Linq.QueryBlock) current_block, sn, (Expression)$5, GetLocation ($1));
6935                 lbag.AddLocation ($$, GetLocation ($3));
6936
6937                 current_block.SetEndLocation (lexer.Location);
6938                 current_block = current_block.Parent;
6939
6940                 ((Linq.QueryBlock)current_block).AddRangeVariable (sn);
6941           }
6942         ;
6943
6944 where_clause
6945         : WHERE
6946           {
6947                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6948           }
6949           expression_or_error
6950           {
6951                 $$ = new Linq.Where ((Linq.QueryBlock)current_block, (Expression)$3, GetLocation ($1));
6952
6953                 current_block.SetEndLocation (lexer.Location);
6954                 current_block = current_block.Parent;
6955           }
6956         ;
6957
6958 join_clause
6959         : JOIN identifier_inside_body IN
6960           {
6961                 if (linq_clause_blocks == null)
6962                         linq_clause_blocks = new Stack<Linq.QueryBlock> ();
6963
6964                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6965                 linq_clause_blocks.Push ((Linq.QueryBlock) current_block);
6966           }
6967           expression_or_error ON
6968           {
6969                 current_block.SetEndLocation (lexer.Location);
6970                 current_block = current_block.Parent;
6971
6972                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6973                 linq_clause_blocks.Push ((Linq.QueryBlock) current_block);
6974           }
6975           expression_or_error EQUALS
6976           {
6977                 current_block.AddStatement (new ContextualReturn ((Expression) $8));
6978                 current_block.SetEndLocation (lexer.Location);
6979                 current_block = current_block.Parent;
6980
6981                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
6982           }
6983           expression_or_error opt_join_into
6984           {
6985                 current_block.AddStatement (new ContextualReturn ((Expression) $11));
6986                 current_block.SetEndLocation (lexer.Location);
6987
6988                 var outer_selector = linq_clause_blocks.Pop ();
6989                 var block = linq_clause_blocks.Pop ();
6990
6991                 var lt = (LocatedToken) $2;
6992                 var sn = new Linq.RangeVariable (lt.Value, lt.Location);
6993                 Linq.RangeVariable into;
6994
6995                 if ($12 == null) {
6996                         into = sn;
6997                         $$ = new Linq.Join (block, sn, (Expression)$5, outer_selector, (Linq.QueryBlock) current_block, GetLocation ($1));
6998                         lbag.AddLocation ($$, GetLocation ($3), GetLocation ($6), GetLocation ($9));
6999                 } else {
7000                         //
7001                         // Set equals right side parent to beginning of linq query, it is not accessible therefore cannot cause name collisions
7002                         //
7003                         var parent = block.Parent;
7004                         while (parent is Linq.QueryBlock) {
7005                                 parent = parent.Parent;
7006                         }
7007                         current_block.Parent = parent;
7008
7009                         ((Linq.QueryBlock)current_block).AddRangeVariable (sn);
7010
7011                         lt = (LocatedToken) $12;
7012                         into = new Linq.RangeVariable (lt.Value, lt.Location);
7013
7014                         $$ = new Linq.GroupJoin (block, sn, (Expression)$5, outer_selector, (Linq.QueryBlock) current_block, into, GetLocation ($1));
7015                         lbag.AddLocation ($$, GetLocation ($3), GetLocation ($6), GetLocation ($9), GetLocation ($12));
7016                 }
7017
7018                 current_block = block.Parent;
7019                 ((Linq.QueryBlock)current_block).AddRangeVariable (into);
7020           }
7021         | JOIN type identifier_inside_body IN
7022           {
7023                 if (linq_clause_blocks == null)
7024                         linq_clause_blocks = new Stack<Linq.QueryBlock> ();
7025
7026                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
7027                 linq_clause_blocks.Push ((Linq.QueryBlock) current_block);
7028           }
7029           expression_or_error ON
7030           {
7031                 current_block.SetEndLocation (lexer.Location);
7032                 current_block = current_block.Parent;
7033
7034                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
7035                 linq_clause_blocks.Push ((Linq.QueryBlock) current_block);
7036           }
7037           expression_or_error EQUALS
7038           {
7039                 current_block.AddStatement (new ContextualReturn ((Expression) $9));
7040                 current_block.SetEndLocation (lexer.Location);
7041                 current_block = current_block.Parent;
7042
7043                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
7044           }
7045           expression_or_error opt_join_into
7046           {
7047                 current_block.AddStatement (new ContextualReturn ((Expression) $12));
7048                 current_block.SetEndLocation (lexer.Location);
7049
7050                 var outer_selector = linq_clause_blocks.Pop ();
7051                 var block = linq_clause_blocks.Pop ();
7052
7053                 var lt = (LocatedToken) $3;
7054                 var sn = new Linq.RangeVariable (lt.Value, lt.Location);
7055                 Linq.RangeVariable into;
7056
7057                 if ($13 == null) {
7058                         into = sn;
7059                         $$ = new Linq.Join (block, sn, (Expression)$6, outer_selector, (Linq.QueryBlock) current_block, GetLocation ($1)) {
7060                                 IdentifierType = (FullNamedExpression)$2
7061                         };
7062                         lbag.AddLocation ($$, GetLocation ($3), GetLocation ($6), GetLocation ($9));
7063                 } else {
7064                         //
7065                         // Set equals right side parent to beginning of linq query, it is not accessible therefore cannot cause name collisions
7066                         //
7067                         var parent = block.Parent;
7068                         while (parent is Linq.QueryBlock) {
7069                                 parent = parent.Parent;
7070                         }
7071                         current_block.Parent = parent;
7072
7073                         ((Linq.QueryBlock)current_block).AddRangeVariable (sn);
7074
7075                         lt = (LocatedToken) $13;
7076                         into = new Linq.RangeVariable (lt.Value, lt.Location); // TODO:
7077
7078                         $$ = new Linq.GroupJoin (block, sn, (Expression)$6, outer_selector, (Linq.QueryBlock) current_block, into, GetLocation ($1)) {
7079                                 IdentifierType = (FullNamedExpression)$2
7080                         };
7081                 }
7082
7083                 current_block = block.Parent;
7084                 ((Linq.QueryBlock)current_block).AddRangeVariable (into);
7085           }
7086         ;
7087
7088 opt_join_into
7089         : /* empty */
7090         | INTO identifier_inside_body
7091           {
7092                 $$ = $2;
7093           }
7094         ;
7095
7096 orderby_clause
7097         : ORDERBY
7098           {
7099                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
7100           }
7101           orderings
7102           {
7103                 current_block.SetEndLocation (lexer.Location);
7104                 current_block = current_block.Parent;
7105
7106                 $$ = $3;
7107           }
7108         ;
7109
7110 orderings
7111         : order_by
7112         | order_by COMMA
7113           {
7114                 current_block.SetEndLocation (lexer.Location);
7115                 current_block = current_block.Parent;
7116
7117                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
7118           }
7119           orderings_then_by
7120           {
7121                 ((Linq.AQueryClause)$1).Next = (Linq.AQueryClause)$4;
7122                 $$ = $1;
7123           }
7124         ;
7125
7126 orderings_then_by
7127         : then_by
7128         | orderings_then_by COMMA
7129          {
7130                 current_block.SetEndLocation (lexer.Location);
7131                 current_block = current_block.Parent;
7132
7133                 current_block = new Linq.QueryBlock ((Linq.QueryBlock) current_block, lexer.Location);
7134          }
7135          then_by
7136          {
7137                 ((Linq.AQueryClause)$1).Tail.Next = (Linq.AQueryClause)$4;
7138                 $$ = $1;
7139          }
7140         ;
7141
7142 order_by
7143         : expression
7144           {
7145                 $$ = new Linq.OrderByAscending ((Linq.QueryBlock) current_block, (Expression)$1);
7146           }
7147         | expression ASCENDING
7148           {
7149                 $$ = new Linq.OrderByAscending ((Linq.QueryBlock) current_block, (Expression)$1);
7150                 lbag.AddLocation ($$, GetLocation ($2));
7151           }
7152         | expression DESCENDING
7153           {
7154                 $$ = new Linq.OrderByDescending ((Linq.QueryBlock) current_block, (Expression)$1);
7155                 lbag.AddLocation ($$, GetLocation ($2));
7156           }
7157         ;
7158
7159 then_by
7160         : expression
7161           {
7162                 $$ = new Linq.ThenByAscending ((Linq.QueryBlock) current_block, (Expression)$1);
7163           }
7164         | expression ASCENDING
7165           {
7166                 $$ = new Linq.ThenByAscending ((Linq.QueryBlock) current_block, (Expression)$1);
7167                 lbag.AddLocation ($$, GetLocation ($2));
7168           }
7169         | expression DESCENDING
7170           {
7171                 $$ = new Linq.ThenByDescending ((Linq.QueryBlock) current_block, (Expression)$1);
7172                 lbag.AddLocation ($$, GetLocation ($2));
7173           }
7174         ;
7175
7176
7177 opt_query_continuation
7178         : /* empty */
7179         | INTO identifier_inside_body
7180           {
7181                 // query continuation block is not linked with query block but with block
7182                 // before. This means each query can use same range variable names for
7183                 // different identifiers.
7184
7185                 current_block.SetEndLocation (GetLocation ($1));
7186                 current_block = current_block.Parent;
7187
7188                 current_block = new Linq.QueryBlock (current_block, lexer.Location);
7189
7190                 if (linq_clause_blocks == null)
7191                         linq_clause_blocks = new Stack<Linq.QueryBlock> ();
7192
7193                 linq_clause_blocks.Push ((Linq.QueryBlock) current_block);
7194           }
7195           query_body
7196           {
7197                 var current_block = linq_clause_blocks.Pop ();
7198                 var lt = (LocatedToken) $2;
7199                 var rv = new Linq.RangeVariable (lt.Value, lt.Location);
7200                 $$ = new Linq.QueryStartClause ((Linq.QueryBlock)current_block, null, rv, GetLocation ($1)) {
7201                         next = (Linq.AQueryClause)$4
7202                 };
7203           }
7204         ;
7205
7206 //
7207 // Support for using the compiler as an interactive parser
7208 //
7209 // The INTERACTIVE_PARSER token is first sent to parse our
7210 // productions;  If the result is a Statement, the parsing
7211 // is repeated, this time with INTERACTIVE_PARSE_WITH_BLOCK
7212 // to setup the blocks in advance.
7213 //
7214 // This setup is here so that in the future we can add
7215 // support for other constructs (type parsing, namespaces, etc)
7216 // that do not require a block to be setup in advance
7217 //
7218
7219 interactive_parsing
7220         : EVAL_STATEMENT_PARSER EOF
7221         | EVAL_USING_DECLARATIONS_UNIT_PARSER using_directives opt_COMPLETE_COMPLETION
7222         | EVAL_STATEMENT_PARSER
7223          {
7224                 current_container = current_type = new Class (current_container, new MemberName ("<InteractiveExpressionClass>"), Modifiers.PUBLIC, null);
7225
7226                 // (ref object retval)
7227                 Parameter [] mpar = new Parameter [1];
7228                 mpar [0] = new Parameter (new TypeExpression (compiler.BuiltinTypes.Object, Location.Null), "$retval", Parameter.Modifier.REF, null, Location.Null);
7229
7230                 ParametersCompiled pars = new ParametersCompiled (mpar);
7231                 var mods = Modifiers.PUBLIC | Modifiers.STATIC;
7232                 if (settings.Unsafe)
7233                         mods |= Modifiers.UNSAFE;
7234
7235                 current_local_parameters = pars;
7236                 var method = new InteractiveMethod (
7237                         current_type,
7238                         new TypeExpression (compiler.BuiltinTypes.Void, Location.Null),
7239                         mods,
7240                         pars);
7241
7242                 current_type.AddMember (method);
7243                 oob_stack.Push (method);
7244
7245                 interactive_async = false;
7246
7247                 ++lexer.parsing_block;
7248                 start_block (lexer.Location);
7249           }
7250           interactive_statement_list opt_COMPLETE_COMPLETION
7251           {
7252                 --lexer.parsing_block;
7253                 var method = (InteractiveMethod) oob_stack.Pop ();
7254                 method.Block = (ToplevelBlock) end_block(lexer.Location);
7255
7256                 if (interactive_async == true) {
7257                         method.ChangeToAsync ();
7258                 }
7259
7260                 InteractiveResult = (Class) pop_current_class ();
7261                 current_local_parameters = null;
7262           }
7263         | EVAL_COMPILATION_UNIT_PARSER interactive_compilation_unit
7264         ;
7265
7266 interactive_compilation_unit
7267         : opt_extern_alias_directives opt_using_directives
7268         | opt_extern_alias_directives opt_using_directives namespace_or_type_declarations
7269         ;
7270
7271 opt_COMPLETE_COMPLETION
7272         : /* nothing */
7273         | COMPLETE_COMPLETION
7274         ;
7275
7276 close_brace_or_complete_completion
7277         : CLOSE_BRACE
7278         | COMPLETE_COMPLETION
7279         ;
7280
7281 //
7282 // XML documentation code references micro parser
7283 //
7284 documentation_parsing
7285         : DOC_SEE doc_cref
7286           {
7287                 module.DocumentationBuilder.ParsedName = (MemberName) $2;
7288           }
7289         ;
7290
7291 doc_cref
7292         : doc_type_declaration_name opt_doc_method_sig
7293           {
7294                 module.DocumentationBuilder.ParsedParameters = (List<DocumentationParameter>)$2;
7295           }
7296         | builtin_types opt_doc_method_sig
7297           {
7298                 module.DocumentationBuilder.ParsedBuiltinType = (TypeExpression)$1;
7299                 module.DocumentationBuilder.ParsedParameters = (List<DocumentationParameter>)$2;
7300                 $$ = null;
7301           }
7302         | VOID opt_doc_method_sig
7303           {
7304                 module.DocumentationBuilder.ParsedBuiltinType = new TypeExpression (compiler.BuiltinTypes.Void, GetLocation ($1));
7305                 module.DocumentationBuilder.ParsedParameters = (List<DocumentationParameter>)$2;
7306                 $$ = null;
7307           }
7308         | builtin_types DOT IDENTIFIER opt_doc_method_sig
7309           {
7310                 module.DocumentationBuilder.ParsedBuiltinType = (TypeExpression)$1;
7311                 module.DocumentationBuilder.ParsedParameters = (List<DocumentationParameter>)$4;
7312                 var lt = (LocatedToken) $3;
7313                 $$ = new MemberName (lt.Value);
7314           }
7315         | doc_type_declaration_name DOT THIS
7316           {
7317                 $$ = new MemberName ((MemberName) $1, MemberCache.IndexerNameAlias, Location.Null);
7318           }
7319         | doc_type_declaration_name DOT THIS OPEN_BRACKET
7320           {
7321                 valid_param_mod = ParameterModifierType.Ref | ParameterModifierType.Out;
7322           }
7323           opt_doc_parameters CLOSE_BRACKET
7324           {
7325                 module.DocumentationBuilder.ParsedParameters = (List<DocumentationParameter>)$6;
7326                 $$ = new MemberName ((MemberName) $1, MemberCache.IndexerNameAlias, Location.Null);
7327           }
7328         | EXPLICIT OPERATOR type opt_doc_method_sig
7329           {
7330                 var p = (List<DocumentationParameter>)$4 ?? new List<DocumentationParameter> (1);
7331                 p.Add (new DocumentationParameter ((FullNamedExpression) $3));
7332                 module.DocumentationBuilder.ParsedParameters = p;
7333                 module.DocumentationBuilder.ParsedOperator = Operator.OpType.Explicit;
7334                 $$ = null;
7335           }
7336         | IMPLICIT OPERATOR type opt_doc_method_sig
7337           {
7338                 var p = (List<DocumentationParameter>)$4 ?? new List<DocumentationParameter> (1);
7339                 p.Add (new DocumentationParameter ((FullNamedExpression) $3));
7340                 module.DocumentationBuilder.ParsedParameters = p;
7341                 module.DocumentationBuilder.ParsedOperator = Operator.OpType.Implicit;
7342                 $$ = null;
7343           }
7344         | OPERATOR overloadable_operator opt_doc_method_sig
7345           {
7346                 var p = (List<DocumentationParameter>)$3;
7347                 module.DocumentationBuilder.ParsedParameters = p;
7348                 module.DocumentationBuilder.ParsedOperator = (Operator.OpType) $2;
7349                 $$ = null;
7350           }
7351         ;
7352
7353 doc_type_declaration_name
7354         : type_declaration_name
7355         | doc_type_declaration_name DOT type_declaration_name
7356           {
7357                 $$ = new MemberName (((MemberName) $1), (MemberName) $3);
7358           }
7359         ;
7360
7361 opt_doc_method_sig
7362         : /* empty */
7363         | OPEN_PARENS
7364           {
7365                 valid_param_mod = ParameterModifierType.Ref | ParameterModifierType.Out;
7366           }
7367           opt_doc_parameters CLOSE_PARENS
7368           {
7369                 $$ = $3;
7370           }
7371         ;
7372
7373 opt_doc_parameters
7374         : /* empty */
7375           {
7376                 $$ = new List<DocumentationParameter> (0);
7377           }
7378         | doc_parameters
7379         ;
7380
7381 doc_parameters
7382         : doc_parameter
7383           {
7384                 var parameters = new List<DocumentationParameter> ();
7385                 parameters.Add ((DocumentationParameter) $1);
7386                 $$ = parameters;
7387           }
7388         | doc_parameters COMMA doc_parameter
7389           {
7390                 var parameters = $1 as List<DocumentationParameter>;
7391                 parameters.Add ((DocumentationParameter) $3);
7392                 $$ = parameters;
7393           }
7394         ;
7395
7396 doc_parameter
7397         : opt_parameter_modifier parameter_type
7398           {
7399                 if ($1 != null)
7400                         $$ = new DocumentationParameter ((Parameter.Modifier) $1, (FullNamedExpression) $2);
7401                 else
7402                         $$ = new DocumentationParameter ((FullNamedExpression) $2);
7403           }
7404         ;
7405
7406 %%
7407
7408 // <summary>
7409 //  A class used to hold info about an operator declarator
7410 // </summary>
7411 class OperatorDeclaration {
7412         public readonly Operator.OpType optype;
7413         public readonly FullNamedExpression ret_type;
7414         public readonly Location location;
7415
7416         public OperatorDeclaration (Operator.OpType op, FullNamedExpression ret_type, Location location)
7417         {
7418                 optype = op;
7419                 this.ret_type = ret_type;
7420                 this.location = location;
7421         }
7422 }
7423
7424 void Error_ExpectingTypeName (Expression expr)
7425 {
7426         if (expr is Invocation){
7427                 report.Error (1002, expr.Location, "Expecting `;'");
7428         } else {
7429                 expr.Error_InvalidExpressionStatement (report);
7430         }
7431 }
7432
7433 void Error_ParameterModifierNotValid (string modifier, Location loc)
7434 {
7435         report.Error (631, loc, "The parameter modifier `{0}' is not valid in this context",
7436                                       modifier);
7437 }
7438
7439 void Error_DuplicateParameterModifier (Location loc, Parameter.Modifier mod)
7440 {
7441         report.Error (1107, loc, "Duplicate parameter modifier `{0}'",
7442                 Parameter.GetModifierSignature (mod));
7443 }
7444
7445 void Error_TypeExpected (Location loc)
7446 {
7447         report.Error (1031, loc, "Type expected");
7448 }
7449
7450 void Error_UnsafeCodeNotAllowed (Location loc)
7451 {
7452         report.Error (227, loc, "Unsafe code requires the `unsafe' command line option to be specified");
7453 }
7454
7455 void Warning_EmptyStatement (Location loc)
7456 {
7457         report.Warning (642, 3, loc, "Possible mistaken empty statement");
7458 }
7459
7460 void Error_NamedArgumentExpected (NamedArgument a)
7461 {
7462         report.Error (1738, a.Location, "Named arguments must appear after the positional arguments");
7463 }
7464
7465 void Error_MissingInitializer (Location loc)
7466 {
7467         report.Error (210, loc, "You must provide an initializer in a fixed or using statement declaration");
7468 }
7469
7470 object Error_AwaitAsIdentifier (object token)
7471 {
7472         if (async_block) {
7473                 report.Error (4003, GetLocation (token), "`await' cannot be used as an identifier within an async method or lambda expression");
7474                 return new LocatedToken ("await", GetLocation (token));
7475         }
7476
7477         return token;
7478 }
7479
7480 void push_current_container (TypeDefinition tc, object partial_token)
7481 {
7482         if (module.Evaluator != null){
7483                 tc.Definition.Modifiers = tc.ModFlags = (tc.ModFlags & ~Modifiers.AccessibilityMask) | Modifiers.PUBLIC;
7484                 if (undo == null)
7485                         undo = new Undo ();
7486
7487                 undo.AddTypeContainer (current_container, tc);
7488         }
7489
7490         if (partial_token != null)
7491                 current_container.AddPartial (tc);
7492         else
7493                 current_container.AddTypeContainer (tc);
7494
7495         ++lexer.parsing_declaration;
7496         current_container = tc;
7497         current_type = tc;
7498 }
7499
7500 TypeContainer pop_current_class ()
7501 {
7502         var retval = current_container;
7503
7504         current_container = current_container.Parent;
7505         current_type = current_type.Parent as TypeDefinition;
7506
7507         return retval;
7508 }
7509
7510 [System.Diagnostics.Conditional ("FULL_AST")]
7511 void StoreModifierLocation (object token, Location loc)
7512 {
7513         if (lbag == null)
7514                 return;
7515
7516         if (mod_locations == null)
7517                 mod_locations = new List<Tuple<Modifiers, Location>> ();
7518
7519         mod_locations.Add (Tuple.Create ((Modifiers) token, loc));
7520 }
7521
7522 [System.Diagnostics.Conditional ("FULL_AST")]
7523 void PushLocation (Location loc)
7524 {
7525         if (location_stack == null)
7526                 location_stack = new Stack<Location> ();
7527
7528         location_stack.Push (loc);
7529 }
7530
7531 Location PopLocation ()
7532 {
7533         if (location_stack == null)
7534                 return Location.Null;
7535
7536         return location_stack.Pop ();
7537 }
7538
7539 string CheckAttributeTarget (int token, string a, Location l)
7540 {
7541         switch (a) {
7542         case "assembly" : case "module" : case "field" : case "method" : case "param" : case "property" : case "type" :
7543                         return a;
7544         }
7545
7546         if (!Tokenizer.IsValidIdentifier (a)) {
7547                 Error_SyntaxError (token);
7548         } else {
7549                 report.Warning (658, 1, l,
7550                          "`{0}' is invalid attribute target. All attributes in this attribute section will be ignored", a);
7551         }
7552
7553         return string.Empty;
7554 }
7555
7556 static bool IsUnaryOperator (Operator.OpType op)
7557 {
7558         switch (op) {
7559
7560         case Operator.OpType.LogicalNot:
7561         case Operator.OpType.OnesComplement:
7562         case Operator.OpType.Increment:
7563         case Operator.OpType.Decrement:
7564         case Operator.OpType.True:
7565         case Operator.OpType.False:
7566         case Operator.OpType.UnaryPlus:
7567         case Operator.OpType.UnaryNegation:
7568                 return true;
7569         }
7570         return false;
7571 }
7572
7573 void syntax_error (Location l, string msg)
7574 {
7575         report.Error (1003, l, "Syntax error, " + msg);
7576 }
7577
7578 Tokenizer lexer;
7579
7580 public Tokenizer Lexer {
7581         get {
7582                 return lexer;
7583         }
7584 }
7585
7586 public CSharpParser (SeekableStreamReader reader, CompilationSourceFile file, ParserSession session)
7587         : this (reader, file, file.Compiler.Report, session)
7588 {
7589 }
7590
7591 public CSharpParser (SeekableStreamReader reader, CompilationSourceFile file, Report report, ParserSession session)
7592 {
7593         this.file = file;
7594         current_container = current_namespace = file;
7595
7596         this.module = file.Module;
7597         this.compiler = file.Compiler;
7598         this.settings = compiler.Settings;
7599         this.report = report;
7600
7601         lang_version = settings.Version;
7602         yacc_verbose_flag = settings.VerboseParserFlag;
7603         doc_support = settings.DocumentationFile != null;
7604         lexer = new Tokenizer (reader, file, session, report);
7605         oob_stack = new Stack<object> ();
7606         lbag = session.LocationsBag;
7607         use_global_stacks = session.UseJayGlobalArrays;
7608         parameters_bucket = session.ParametersStack;
7609 }
7610
7611 public void parse ()
7612 {
7613         eof_token = Token.EOF;
7614
7615         try {
7616                 if (yacc_verbose_flag > 1)
7617                         yyparse (lexer, new yydebug.yyDebugSimple ());
7618                 else
7619                         yyparse (lexer);
7620
7621                 Tokenizer tokenizer = lexer as Tokenizer;
7622                 tokenizer.cleanup ();
7623         } catch (Exception e){
7624                 if (e is yyParser.yyUnexpectedEof) {
7625                         Error_SyntaxError (yyToken);
7626                         UnexpectedEOF = true;
7627                         return;
7628                 }
7629
7630                 if (e is yyParser.yyException) {
7631                         if (report.Errors == 0)
7632                                 report.Error (-25, lexer.Location, "Parsing error");
7633                 } else {
7634                         // Used by compiler-tester to test internal errors
7635                         if (yacc_verbose_flag > 0 || e is FatalException)
7636                                 throw;
7637
7638                         report.Error (589, lexer.Location, "Internal compiler error during parsing" + e);
7639                 }
7640         }
7641 }
7642
7643 void CheckToken (int error, int yyToken, string msg, Location loc)
7644 {
7645         if (yyToken >= Token.FIRST_KEYWORD && yyToken <= Token.LAST_KEYWORD)
7646                 report.Error (error, loc, "{0}: `{1}' is a keyword", msg, GetTokenName (yyToken));
7647         else
7648                 report.Error (error, loc, msg);
7649 }
7650
7651 string ConsumeStoredComment ()
7652 {
7653         string s = tmpComment;
7654         tmpComment = null;
7655         Lexer.doc_state = XmlCommentState.Allowed;
7656         return s;
7657 }
7658
7659 void FeatureIsNotAvailable (Location loc, string feature)
7660 {
7661         report.FeatureIsNotAvailable (compiler, loc, feature);
7662 }
7663
7664 Location GetLocation (object obj)
7665 {
7666         var lt = obj as LocatedToken;
7667         if (lt != null)
7668                 return lt.Location;
7669
7670         var mn = obj as MemberName;
7671         if (mn != null)
7672                 return mn.Location;
7673
7674         var expr = obj as Expression;
7675         if (expr != null)
7676                 return expr.Location;
7677
7678         return lexer.Location;
7679 }
7680
7681 void start_block (Location loc)
7682 {
7683         if (current_block == null) {
7684                 current_block = new ToplevelBlock (compiler, current_local_parameters, loc);
7685                 parsing_anonymous_method = false;
7686         } else if (parsing_anonymous_method) {
7687                 current_block = new ParametersBlock (current_block, current_local_parameters, loc);
7688                 parsing_anonymous_method = false;
7689         } else {
7690                 current_block = new ExplicitBlock (current_block, loc, Location.Null);
7691         }
7692 }
7693
7694 Block
7695 end_block (Location loc)
7696 {
7697         Block retval = current_block.Explicit;
7698         retval.SetEndLocation (loc);
7699         current_block = retval.Parent;
7700         return retval;
7701 }
7702
7703 void start_anonymous (bool isLambda, ParametersCompiled parameters, bool isAsync, Location loc)
7704 {
7705         oob_stack.Push (current_anonymous_method);
7706         oob_stack.Push (current_local_parameters);
7707         oob_stack.Push (current_variable);
7708         oob_stack.Push (async_block);
7709
7710         current_local_parameters = parameters;
7711         if (isLambda) {
7712                 if (lang_version <= LanguageVersion.ISO_2)
7713                         FeatureIsNotAvailable (loc, "lambda expressions");
7714
7715                 current_anonymous_method = new LambdaExpression (loc);
7716         } else {
7717                 if (lang_version == LanguageVersion.ISO_1)
7718                         FeatureIsNotAvailable (loc, "anonymous methods");
7719
7720                 current_anonymous_method = new AnonymousMethodExpression (loc);
7721         }
7722
7723         async_block = isAsync;
7724         // Force the next block to be created as a ToplevelBlock
7725         parsing_anonymous_method = true;
7726 }
7727
7728 /*
7729  * Completes the anonymous method processing, if lambda_expr is null, this
7730  * means that we have a Statement instead of an Expression embedded
7731  */
7732 AnonymousMethodExpression end_anonymous (ParametersBlock anon_block)
7733 {
7734         AnonymousMethodExpression retval;
7735
7736         if (async_block)
7737                 anon_block.IsAsync = true;
7738
7739         current_anonymous_method.Block = anon_block;
7740         retval = current_anonymous_method;
7741
7742         async_block = (bool) oob_stack.Pop ();
7743         current_variable = (BlockVariable) oob_stack.Pop ();
7744         current_local_parameters = (ParametersCompiled) oob_stack.Pop ();
7745         current_anonymous_method = (AnonymousMethodExpression) oob_stack.Pop ();
7746
7747         return retval;
7748 }
7749
7750 void Error_SyntaxError (int token)
7751 {
7752         Error_SyntaxError (0, token);
7753 }
7754
7755 void Error_SyntaxError (int error_code, int token)
7756 {
7757         Error_SyntaxError (error_code, token, "Unexpected symbol");
7758 }
7759
7760 void Error_SyntaxError (int error_code, int token, string msg)
7761 {
7762         Lexer.CompleteOnEOF = false;
7763
7764         // An error message has been reported by tokenizer
7765         if (token == Token.ERROR)
7766                 return;
7767
7768         // Avoid duplicit error message after unterminated string literals
7769         if (token == Token.LITERAL && lexer.Location.Column == 0)
7770                 return;
7771
7772         string symbol = GetSymbolName (token);
7773         string expecting = GetExpecting ();
7774         var loc = lexer.Location - symbol.Length;
7775
7776         if (error_code == 0) {
7777                 if (expecting == "`identifier'") {
7778                         if (token > Token.FIRST_KEYWORD && token < Token.LAST_KEYWORD) {
7779                                 report.Error (1041, loc, "Identifier expected, `{0}' is a keyword", symbol);
7780                                 return;
7781                         }
7782
7783                         error_code = 1001;
7784                         expecting = "identifier";
7785                 } else if (expecting == "`)'") {
7786                         error_code = 1026;
7787                 } else {
7788                         error_code = 1525;
7789                 }
7790         }
7791
7792         if (string.IsNullOrEmpty (expecting))
7793                 report.Error (error_code, loc, "{1} `{0}'", symbol, msg);
7794         else
7795                 report.Error (error_code, loc, "{2} `{0}', expecting {1}", symbol, expecting, msg);
7796 }
7797
7798 string GetExpecting ()
7799 {
7800         int [] tokens = yyExpectingTokens (yyExpectingState);
7801         var names = new List<string> (tokens.Length);
7802         bool has_type = false;
7803         bool has_identifier = false;
7804         for (int i = 0; i < tokens.Length; i++){
7805                 int token = tokens [i];
7806                 has_identifier |= token == Token.IDENTIFIER;
7807
7808                 string name = GetTokenName (token);
7809                 if (name == "<internal>")
7810                         continue;
7811
7812                 has_type |= name == "type";
7813                 if (names.Contains (name))
7814                         continue;
7815
7816                 names.Add (name);
7817         }
7818
7819         //
7820         // Too many tokens to enumerate
7821         //
7822         if (names.Count > 8)
7823                 return null;
7824
7825         if (has_type && has_identifier)
7826                 names.Remove ("identifier");
7827
7828         if (names.Count == 1)
7829                 return "`" + GetTokenName (tokens [0]) + "'";
7830
7831         StringBuilder sb = new StringBuilder ();
7832         names.Sort ();
7833         int count = names.Count;
7834         for (int i = 0; i < count; i++){
7835                 bool last = i + 1 == count;
7836                 if (last)
7837                         sb.Append ("or ");
7838                 sb.Append ('`');
7839                 sb.Append (names [i]);
7840                 sb.Append (last ? "'" : count < 3 ? "' " : "', ");
7841         }
7842         return sb.ToString ();
7843 }
7844
7845
7846 string GetSymbolName (int token)
7847 {
7848         switch (token){
7849         case Token.LITERAL:
7850                 return ((Constant)lexer.Value).GetValue ().ToString ();
7851         case Token.IDENTIFIER:
7852                 return ((LocatedToken)lexer.Value).Value;
7853
7854         case Token.BOOL:
7855                 return "bool";
7856         case Token.BYTE:
7857                 return "byte";
7858         case Token.CHAR:
7859                 return "char";
7860         case Token.VOID:
7861                 return "void";
7862         case Token.DECIMAL:
7863                 return "decimal";
7864         case Token.DOUBLE:
7865                 return "double";
7866         case Token.FLOAT:
7867                 return "float";
7868         case Token.INT:
7869                 return "int";
7870         case Token.LONG:
7871                 return "long";
7872         case Token.SBYTE:
7873                 return "sbyte";
7874         case Token.SHORT:
7875                 return "short";
7876         case Token.STRING:
7877                 return "string";
7878         case Token.UINT:
7879                 return "uint";
7880         case Token.ULONG:
7881                 return "ulong";
7882         case Token.USHORT:
7883                 return "ushort";
7884         case Token.OBJECT:
7885                 return "object";
7886
7887         case Token.PLUS:
7888                 return "+";
7889         case Token.UMINUS:
7890         case Token.MINUS:
7891                 return "-";
7892         case Token.BANG:
7893                 return "!";
7894         case Token.BITWISE_AND:
7895                 return "&";
7896         case Token.BITWISE_OR:
7897                 return "|";
7898         case Token.STAR:
7899                 return "*";
7900         case Token.PERCENT:
7901                 return "%";
7902         case Token.DIV:
7903                 return "/";
7904         case Token.CARRET:
7905                 return "^";
7906         case Token.OP_INC:
7907                 return "++";
7908         case Token.OP_DEC:
7909                 return "--";
7910         case Token.OP_SHIFT_LEFT:
7911                 return "<<";
7912         case Token.OP_SHIFT_RIGHT:
7913                 return ">>";
7914         case Token.OP_LT:
7915                 return "<";
7916         case Token.OP_GT:
7917                 return ">";
7918         case Token.OP_LE:
7919                 return "<=";
7920         case Token.OP_GE:
7921                 return ">=";
7922         case Token.OP_EQ:
7923                 return "==";
7924         case Token.OP_NE:
7925                 return "!=";
7926         case Token.OP_AND:
7927                 return "&&";
7928         case Token.OP_OR:
7929                 return "||";
7930         case Token.OP_PTR:
7931                 return "->";
7932         case Token.OP_COALESCING:
7933                 return "??";
7934         case Token.OP_MULT_ASSIGN:
7935                 return "*=";
7936         case Token.OP_DIV_ASSIGN:
7937                 return "/=";
7938         case Token.OP_MOD_ASSIGN:
7939                 return "%=";
7940         case Token.OP_ADD_ASSIGN:
7941                 return "+=";
7942         case Token.OP_SUB_ASSIGN:
7943                 return "-=";
7944         case Token.OP_SHIFT_LEFT_ASSIGN:
7945                 return "<<=";
7946         case Token.OP_SHIFT_RIGHT_ASSIGN:
7947                 return ">>=";
7948         case Token.OP_AND_ASSIGN:
7949                 return "&=";
7950         case Token.OP_XOR_ASSIGN:
7951                 return "^=";
7952         case Token.OP_OR_ASSIGN:
7953                 return "|=";
7954         }
7955
7956         return GetTokenName (token);
7957 }
7958
7959 static string GetTokenName (int token)
7960 {
7961         switch (token){
7962         case Token.ABSTRACT:
7963                 return "abstract";
7964         case Token.AS:
7965                 return "as";
7966         case Token.ADD:
7967                 return "add";
7968         case Token.ASYNC:
7969                 return "async";
7970         case Token.BASE:
7971                 return "base";
7972         case Token.BREAK:
7973                 return "break";
7974         case Token.CASE:
7975                 return "case";
7976         case Token.CATCH:
7977                 return "catch";
7978         case Token.CHECKED:
7979                 return "checked";
7980         case Token.CLASS:
7981                 return "class";
7982         case Token.CONST:
7983                 return "const";
7984         case Token.CONTINUE:
7985                 return "continue";
7986         case Token.DEFAULT:
7987                 return "default";
7988         case Token.DELEGATE:
7989                 return "delegate";
7990         case Token.DO:
7991                 return "do";
7992         case Token.ELSE:
7993                 return "else";
7994         case Token.ENUM:
7995                 return "enum";
7996         case Token.EVENT:
7997                 return "event";
7998         case Token.EXPLICIT:
7999                 return "explicit";
8000         case Token.EXTERN:
8001         case Token.EXTERN_ALIAS:
8002                 return "extern";
8003         case Token.FALSE:
8004                 return "false";
8005         case Token.FINALLY:
8006                 return "finally";
8007         case Token.FIXED:
8008                 return "fixed";
8009         case Token.FOR:
8010                 return "for";
8011         case Token.FOREACH:
8012                 return "foreach";
8013         case Token.GOTO:
8014                 return "goto";
8015         case Token.IF:
8016                 return "if";
8017         case Token.IMPLICIT:
8018                 return "implicit";
8019         case Token.IN:
8020                 return "in";
8021         case Token.INTERFACE:
8022                 return "interface";
8023         case Token.INTERNAL:
8024                 return "internal";
8025         case Token.IS:
8026                 return "is";
8027         case Token.LOCK:
8028                 return "lock";
8029         case Token.NAMESPACE:
8030                 return "namespace";
8031         case Token.NEW:
8032                 return "new";
8033         case Token.NULL:
8034                 return "null";
8035         case Token.OPERATOR:
8036                 return "operator";
8037         case Token.OUT:
8038                 return "out";
8039         case Token.OVERRIDE:
8040                 return "override";
8041         case Token.PARAMS:
8042                 return "params";
8043         case Token.PRIVATE:
8044                 return "private";
8045         case Token.PROTECTED:
8046                 return "protected";
8047         case Token.PUBLIC:
8048                 return "public";
8049         case Token.READONLY:
8050                 return "readonly";
8051         case Token.REF:
8052                 return "ref";
8053         case Token.RETURN:
8054                 return "return";
8055         case Token.REMOVE:
8056                 return "remove";
8057         case Token.SEALED:
8058                 return "sealed";
8059         case Token.SIZEOF:
8060                 return "sizeof";
8061         case Token.STACKALLOC:
8062                 return "stackalloc";
8063         case Token.STATIC:
8064                 return "static";
8065         case Token.STRUCT:
8066                 return "struct";
8067         case Token.SWITCH:
8068                 return "switch";
8069         case Token.THIS:
8070                 return "this";
8071         case Token.THROW:
8072                 return "throw";
8073         case Token.TRUE:
8074                 return "true";
8075         case Token.TRY:
8076                 return "try";
8077         case Token.TYPEOF:
8078                 return "typeof";
8079         case Token.UNCHECKED:
8080                 return "unchecked";
8081         case Token.UNSAFE:
8082                 return "unsafe";
8083         case Token.USING:
8084                 return "using";
8085         case Token.VIRTUAL:
8086                 return "virtual";
8087         case Token.VOLATILE:
8088                 return "volatile";
8089         case Token.WHERE:
8090                 return "where";
8091         case Token.WHILE:
8092                 return "while";
8093         case Token.ARGLIST:
8094                 return "__arglist";
8095         case Token.REFVALUE:
8096                 return "__refvalue";
8097         case Token.REFTYPE:
8098                 return "__reftype";
8099         case Token.MAKEREF:
8100                 return "__makeref";
8101         case Token.PARTIAL:
8102                 return "partial";
8103         case Token.ARROW:
8104                 return "=>";
8105         case Token.FROM:
8106         case Token.FROM_FIRST:
8107                 return "from";
8108         case Token.JOIN:
8109                 return "join";
8110         case Token.ON:
8111                 return "on";
8112         case Token.EQUALS:
8113                 return "equals";
8114         case Token.SELECT:
8115                 return "select";
8116         case Token.GROUP:
8117                 return "group";
8118         case Token.BY:
8119                 return "by";
8120         case Token.LET:
8121                 return "let";
8122         case Token.ORDERBY:
8123                 return "orderby";
8124         case Token.ASCENDING:
8125                 return "ascending";
8126         case Token.DESCENDING:
8127                 return "descending";
8128         case Token.INTO:
8129                 return "into";
8130         case Token.GET:
8131                 return "get";
8132         case Token.SET:
8133                 return "set";
8134         case Token.OPEN_BRACE:
8135                 return "{";
8136         case Token.CLOSE_BRACE:
8137                 return "}";
8138         case Token.OPEN_BRACKET:
8139         case Token.OPEN_BRACKET_EXPR:
8140                 return "[";
8141         case Token.CLOSE_BRACKET:
8142                 return "]";
8143         case Token.OPEN_PARENS_CAST:
8144         case Token.OPEN_PARENS_LAMBDA:
8145         case Token.OPEN_PARENS:
8146                 return "(";
8147         case Token.CLOSE_PARENS:
8148                 return ")";
8149         case Token.DOT:
8150                 return ".";
8151         case Token.COMMA:
8152                 return ",";
8153         case Token.DEFAULT_COLON:
8154                 return "default:";
8155         case Token.COLON:
8156                 return ":";
8157         case Token.SEMICOLON:
8158                 return ";";
8159         case Token.TILDE:
8160                 return "~";
8161         case Token.WHEN:
8162                 return "when";
8163         case Token.INTERPOLATED_STRING_END:
8164                 return "}";
8165         case Token.INTERPOLATED_STRING:
8166                 return "${";
8167
8168         case Token.PLUS:
8169         case Token.UMINUS:
8170         case Token.MINUS:
8171         case Token.BANG:
8172         case Token.OP_LT:
8173         case Token.OP_GT:
8174         case Token.BITWISE_AND:
8175         case Token.BITWISE_OR:
8176         case Token.STAR:
8177         case Token.PERCENT:
8178         case Token.DIV:
8179         case Token.CARRET:
8180         case Token.OP_INC:
8181         case Token.OP_DEC:
8182         case Token.OP_SHIFT_LEFT:
8183         case Token.OP_SHIFT_RIGHT:
8184         case Token.OP_LE:
8185         case Token.OP_GE:
8186         case Token.OP_EQ:
8187         case Token.OP_NE:
8188         case Token.OP_AND:
8189         case Token.OP_OR:
8190         case Token.OP_PTR:
8191         case Token.OP_COALESCING:
8192         case Token.OP_MULT_ASSIGN:
8193         case Token.OP_DIV_ASSIGN:
8194         case Token.OP_MOD_ASSIGN:
8195         case Token.OP_ADD_ASSIGN:
8196         case Token.OP_SUB_ASSIGN:
8197         case Token.OP_SHIFT_LEFT_ASSIGN:
8198         case Token.OP_SHIFT_RIGHT_ASSIGN:
8199         case Token.OP_AND_ASSIGN:
8200         case Token.OP_XOR_ASSIGN:
8201         case Token.OP_OR_ASSIGN:
8202         case Token.INTERR_OPERATOR:
8203                 return "<operator>";
8204
8205         case Token.BOOL:
8206         case Token.BYTE:
8207         case Token.CHAR:
8208         case Token.VOID:
8209         case Token.DECIMAL:
8210         case Token.DOUBLE:
8211         case Token.FLOAT:
8212         case Token.INT:
8213         case Token.LONG:
8214         case Token.SBYTE:
8215         case Token.SHORT:
8216         case Token.STRING:
8217         case Token.UINT:
8218         case Token.ULONG:
8219         case Token.USHORT:
8220         case Token.OBJECT:
8221                 return "type";
8222
8223         case Token.ASSIGN:
8224                 return "=";
8225         case Token.OP_GENERICS_LT:
8226         case Token.GENERIC_DIMENSION:
8227                 return "<";
8228         case Token.OP_GENERICS_GT:
8229                 return ">";
8230         case Token.INTERR:
8231         case Token.INTERR_NULLABLE:
8232                 return "?";
8233         case Token.DOUBLE_COLON:
8234                 return "::";
8235         case Token.LITERAL:
8236                 return "value";
8237         case Token.IDENTIFIER:
8238         case Token.AWAIT:
8239                 return "identifier";
8240
8241         case Token.EOF:
8242                 return "end-of-file";
8243
8244                 // All of these are internal.
8245         case Token.NONE:
8246         case Token.ERROR:
8247         case Token.FIRST_KEYWORD:
8248         case Token.EVAL_COMPILATION_UNIT_PARSER:
8249         case Token.EVAL_USING_DECLARATIONS_UNIT_PARSER:
8250         case Token.EVAL_STATEMENT_PARSER:
8251         case Token.LAST_KEYWORD:
8252         case Token.GENERATE_COMPLETION:
8253         case Token.COMPLETE_COMPLETION:
8254                 return "<internal>";
8255
8256                 // A bit more robust.
8257         default:
8258                 return yyNames [token];
8259         }
8260 }
8261
8262 /* end end end */
8263 }