mcs/mcs/enum.cs

   1 //
   2 // enum.cs: Enum handling.
   3 //
   4 // Author: Miguel de Icaza (miguel@gnu.org)
   5 //         Ravi Pratap     (ravi@ximian.com)
   6 //
   7 // Licensed under the terms of the GNU GPL
   8 //
   9 // (C) 2001 Ximian, Inc (http://www.ximian.com)
  10 //
  11
  12 using System;
  13 using System.Collections;
  14 using System.Reflection;
  15 using System.Reflection.Emit;
  16 using System.Globalization;
  17
  18 namespace Mono.CSharp {
  19
  20         class EnumMember: MemberCore {
  21                 static string[] attribute_targets = new string [] { "field" };
  22
  23                 Enum parent_enum;
  24                 public FieldBuilder builder;
  25
  26                 public EnumMember (Enum parent_enum, string name, Location loc, Attributes attrs):
  27                         base (null, name, attrs, loc)
  28                 {
  29                         this.parent_enum = parent_enum;
  30                 }
  31
  32                 public override void ApplyAttributeBuilder(Attribute a, CustomAttributeBuilder cb)
  33                 {
  34                         if (a.Type == TypeManager.marshal_as_attr_type) {
  35                                 UnmanagedMarshal marshal = a.GetMarshal ();
  36                                 if (marshal != null) {
  37                                         builder.SetMarshal (marshal);
  38                                         return;
  39                                 }
  40                                 Report.Warning (-24, a.Location, "The Microsoft Runtime cannot set this marshal info. Please use the Mono runtime instead.");
  41                                 return;
  42                         }
  43
  44                         builder.SetCustomAttribute (cb);
  45                 }
  46
  47                 public override AttributeTargets AttributeTargets {
  48                         get {
  49                                 return AttributeTargets.Field;
  50                         }
  51                 }
  52
  53                 public override bool IsClsCompliaceRequired (DeclSpace ds)
  54                 {
  55                         return parent_enum.IsClsCompliaceRequired (ds);
  56                 }
  57
  58                 public void DefineMember (TypeBuilder tb)
  59                 {
  60                         FieldAttributes attr = FieldAttributes.Public | FieldAttributes.Static
  61                                 | FieldAttributes.Literal;
  62
  63                         builder = tb.DefineField (Name, tb, attr);
  64                 }
  65
  66                 public override bool Define ()
  67                 {
  68                         throw new NotImplementedException ();
  69                 }
  70
  71                 public void Emit (EmitContext ec)
  72                 {
  73                         if (OptAttributes != null)
  74                                 OptAttributes.Emit (ec, this);
  75                 }
  76
  77                 // TODO: caching would be usefull
  78                 public ObsoleteAttribute GetObsoleteAttribute (EmitContext ec)
  79                 {
  80                         if (OptAttributes == null)
  81                                 return null;
  82
  83                         Attribute obsolete_attr = OptAttributes.Search (TypeManager.obsolete_attribute_type, ec);
  84                         if (obsolete_attr == null)
  85                                 return null;
  86
  87                         ObsoleteAttribute obsolete = obsolete_attr.GetObsoleteAttribute (ec.DeclSpace);
  88                         if (obsolete == null)
  89                                 return null;
  90
  91                         return obsolete;
  92                 }
  93
  94                 public override string[] ValidAttributeTargets {
  95                         get {
  96                                 return attribute_targets;
  97                         }
  98                 }
  99
 100                 protected override void VerifyObsoleteAttribute()
 101                 {
 102                         throw new NotImplementedException ();
 103                 }
 104
 105         }
 106
 107         /// <summary>
 108         ///   Enumeration container
 109         /// </summary>
 110         public class Enum : DeclSpace {
 111                 ArrayList ordered_enums;
 112
 113                 public Expression BaseType;
 114
 115                 public Type UnderlyingType;
 116
 117                 Hashtable member_to_location;
 118                 Hashtable member_to_attributes;
 119
 120                 //
 121                 // This is for members that have been defined
 122                 //
 123                 Hashtable member_to_value;
 124
 125                 //
 126                 // This is used to mark members we're currently defining
 127                 //
 128                 Hashtable in_transit;
 129
 130                 ArrayList field_builders;
 131
 132
 133                 Hashtable name_to_member;
 134
 135                 public const int AllowedModifiers =
 136                         Modifiers.NEW |
 137                         Modifiers.PUBLIC |
 138                         Modifiers.PROTECTED |
 139                         Modifiers.INTERNAL |
 140                         Modifiers.PRIVATE;
 141
 142                 public Enum (NamespaceEntry ns, TypeContainer parent, Expression type, int mod_flags,
 143                              string name, Attributes attrs, Location l)
 144                         : base (ns, parent, name, attrs, l)
 145                 {
 146                         this.BaseType = type;
 147                         ModFlags = Modifiers.Check (AllowedModifiers, mod_flags,
 148                                                     IsTopLevel ? Modifiers.INTERNAL : Modifiers.PRIVATE, l);
 149
 150                         ordered_enums = new ArrayList ();
 151                         member_to_location = new Hashtable ();
 152                         member_to_value = new Hashtable ();
 153                         in_transit = new Hashtable ();
 154                         field_builders = new ArrayList ();
 155
 156                         name_to_member = new Hashtable ();
 157                 }
 158
 159                 /// <summary>
 160                 ///   Adds @name to the enumeration space, with @expr
 161                 ///   being its definition.
 162                 /// </summary>
 163                 public AdditionResult AddEnumMember (string name, Expression expr, Location loc,
 164                                                      Attributes opt_attrs)
 165                 {
 166                         if (defined_names.Contains (name))
 167                                 return AdditionResult.NameExists;
 168
 169                         if (name == "value__") {
 170                                 Report.Error (76, loc, "An item in an enumeration can't have an identifier `value__'");
 171                                 return AdditionResult.Error;
 172                         }
 173
 174                         DefineName (name, expr);
 175
 176                         ordered_enums.Add (name);
 177                         member_to_location.Add (name, loc);
 178
 179                         if (member_to_attributes == null)
 180                                 member_to_attributes = new Hashtable ();
 181
 182                         member_to_attributes.Add (name, opt_attrs);
 183
 184                         name_to_member.Add (name, new EnumMember (this, name, loc, opt_attrs));
 185
 186                         return AdditionResult.Success;
 187                 }
 188
 189                 //
 190                 // This is used by corlib compilation: we map from our
 191                 // type to a type that is consumable by the DefineField
 192                 //
 193                 Type MapToInternalType (Type t)
 194                 {
 195                         if (t == TypeManager.int32_type)
 196                                 return typeof (int);
 197                         if (t == TypeManager.int64_type)
 198                                 return typeof (long);
 199                         if (t == TypeManager.uint32_type)
 200                                 return typeof (uint);
 201                         if (t == TypeManager.uint64_type)
 202                                 return typeof (ulong);
 203                         if (t == TypeManager.float_type)
 204                                 return typeof (float);
 205                         if (t == TypeManager.double_type)
 206                                 return typeof (double);
 207                         if (t == TypeManager.byte_type)
 208                                 return typeof (byte);
 209                         if (t == TypeManager.sbyte_type)
 210                                 return typeof (sbyte);
 211                         if (t == TypeManager.char_type)
 212                                 return typeof (char);
 213                         if (t == TypeManager.short_type)
 214                                 return typeof (short);
 215                         if (t == TypeManager.ushort_type)
 216                                 return typeof (ushort);
 217
 218                         throw new Exception ();
 219                 }
 220
 221                 public override TypeBuilder DefineType ()
 222                 {
 223                         if (TypeBuilder != null)
 224                                 return TypeBuilder;
 225
 226                         TypeAttributes attr = Modifiers.TypeAttr (ModFlags, IsTopLevel);
 227
 228                         attr |= TypeAttributes.Class | TypeAttributes.Sealed;
 229
 230                         if (!(BaseType is TypeLookupExpression)) {
 231                                 Report.Error (1008, Location,
 232                                               "Type byte, sbyte, short, ushort, int, uint, " +
 233                                               "long, or ulong expected (got: `{0}')", BaseType);
 234                                 return null;
 235                         }
 236
 237                         UnderlyingType = ResolveType (BaseType, false, Location);
 238
 239                         if (UnderlyingType != TypeManager.int32_type &&
 240                             UnderlyingType != TypeManager.uint32_type &&
 241                             UnderlyingType != TypeManager.int64_type &&
 242                             UnderlyingType != TypeManager.uint64_type &&
 243                             UnderlyingType != TypeManager.short_type &&
 244                             UnderlyingType != TypeManager.ushort_type &&
 245                             UnderlyingType != TypeManager.byte_type  &&
 246                             UnderlyingType != TypeManager.sbyte_type) {
 247                                 Report.Error (1008, Location,
 248                                               "Type byte, sbyte, short, ushort, int, uint, " +
 249                                               "long, or ulong expected (got: " +
 250                                               TypeManager.CSharpName (UnderlyingType) + ")");
 251                                 return null;
 252                         }
 253
 254                         if (IsTopLevel) {
 255                                 if (TypeManager.NamespaceClash (Name, Location))
 256                                         return null;
 257
 258                                 ModuleBuilder builder = CodeGen.Module.Builder;
 259
 260                                 TypeBuilder = builder.DefineType (Name, attr, TypeManager.enum_type);
 261                         } else {
 262                                 TypeBuilder builder = Parent.TypeBuilder;
 263
 264                                 TypeBuilder = builder.DefineNestedType (
 265                                         Basename, attr, TypeManager.enum_type);
 266                         }
 267
 268                         //
 269                         // Call MapToInternalType for corlib
 270                         //
 271                         TypeBuilder.DefineField ("value__", UnderlyingType,
 272                                                  FieldAttributes.Public | FieldAttributes.SpecialName
 273                                                  | FieldAttributes.RTSpecialName);
 274
 275                         TypeManager.AddEnumType (Name, TypeBuilder, this);
 276
 277                         return TypeBuilder;
 278                 }
 279
 280                 bool IsValidEnumConstant (Expression e)
 281                 {
 282                         if (!(e is Constant))
 283                                 return false;
 284
 285                         if (e is IntConstant || e is UIntConstant || e is LongConstant ||
 286                             e is ByteConstant || e is SByteConstant || e is ShortConstant ||
 287                             e is UShortConstant || e is ULongConstant || e is EnumConstant ||
 288                             e is CharConstant)
 289                                 return true;
 290                         else
 291                                 return false;
 292                 }
 293
 294                 object GetNextDefaultValue (object default_value)
 295                 {
 296                         if (UnderlyingType == TypeManager.int32_type) {
 297                                 int i = (int) default_value;
 298
 299                                 if (i < System.Int32.MaxValue)
 300                                         return ++i;
 301                                 else
 302                                         return null;
 303                         } else if (UnderlyingType == TypeManager.uint32_type) {
 304                                 uint i = (uint) default_value;
 305
 306                                 if (i < System.UInt32.MaxValue)
 307                                         return ++i;
 308                                 else
 309                                         return null;
 310                         } else if (UnderlyingType == TypeManager.int64_type) {
 311                                 long i = (long) default_value;
 312
 313                                 if (i < System.Int64.MaxValue)
 314                                         return ++i;
 315                                 else
 316                                         return null;
 317                         } else if (UnderlyingType == TypeManager.uint64_type) {
 318                                 ulong i = (ulong) default_value;
 319
 320                                 if (i < System.UInt64.MaxValue)
 321                                         return ++i;
 322                                 else
 323                                         return null;
 324                         } else if (UnderlyingType == TypeManager.short_type) {
 325                                 short i = (short) default_value;
 326
 327                                 if (i < System.Int16.MaxValue)
 328                                         return ++i;
 329                                 else
 330                                         return null;
 331                         } else if (UnderlyingType == TypeManager.ushort_type) {
 332                                 ushort i = (ushort) default_value;
 333
 334                                 if (i < System.UInt16.MaxValue)
 335                                         return ++i;
 336                                 else
 337                                         return null;
 338                         } else if (UnderlyingType == TypeManager.byte_type) {
 339                                 byte i = (byte) default_value;
 340
 341                                 if (i < System.Byte.MaxValue)
 342                                         return ++i;
 343                                 else
 344                                         return null;
 345                         } else if (UnderlyingType == TypeManager.sbyte_type) {
 346                                 sbyte i = (sbyte) default_value;
 347
 348                                 if (i < System.SByte.MaxValue)
 349                                         return ++i;
 350                                 else
 351                                         return null;
 352                         }
 353
 354                         return null;
 355                 }
 356
 357                 void Error_ConstantValueCannotBeConverted (object val, Location loc)
 358                 {
 359                         if (val is Constant)
 360                                 Report.Error (31, loc, "Constant value '" + ((Constant) val).AsString () +
 361                                               "' cannot be converted" +
 362                                               " to a " + TypeManager.CSharpName (UnderlyingType));
 363                         else
 364                                 Report.Error (31, loc, "Constant value '" + val +
 365                                               "' cannot be converted" +
 366                                               " to a " + TypeManager.CSharpName (UnderlyingType));
 367                         return;
 368                 }
 369
 370                 /// <summary>
 371                 ///  Determines if a standard implicit conversion exists from
 372                 ///  expr_type to target_type
 373                 /// </summary>
 374                 public static bool ImplicitConversionExists (Type expr_type, Type target_type)
 375                 {
 376                         expr_type = TypeManager.TypeToCoreType (expr_type);
 377
 378                         if (expr_type == TypeManager.void_type)
 379                                 return false;
 380
 381                         if (expr_type == target_type)
 382                                 return true;
 383
 384                         // First numeric conversions
 385
 386                         if (expr_type == TypeManager.sbyte_type){
 387                                 //
 388                                 // From sbyte to short, int, long, float, double.
 389                                 //
 390                                 if ((target_type == TypeManager.int32_type) ||
 391                                     (target_type == TypeManager.int64_type) ||
 392                                     (target_type == TypeManager.double_type) ||
 393                                     (target_type == TypeManager.float_type)  ||
 394                                     (target_type == TypeManager.short_type) ||
 395                                     (target_type == TypeManager.decimal_type))
 396                                         return true;
 397
 398                         } else if (expr_type == TypeManager.byte_type){
 399                                 //
 400                                 // From byte to short, ushort, int, uint, long, ulong, float, double
 401                                 //
 402                                 if ((target_type == TypeManager.short_type) ||
 403                                     (target_type == TypeManager.ushort_type) ||
 404                                     (target_type == TypeManager.int32_type) ||
 405                                     (target_type == TypeManager.uint32_type) ||
 406                                     (target_type == TypeManager.uint64_type) ||
 407                                     (target_type == TypeManager.int64_type) ||
 408                                     (target_type == TypeManager.float_type) ||
 409                                     (target_type == TypeManager.double_type) ||
 410                                     (target_type == TypeManager.decimal_type))
 411                                         return true;
 412
 413                         } else if (expr_type == TypeManager.short_type){
 414                                 //
 415                                 // From short to int, long, float, double
 416                                 //
 417                                 if ((target_type == TypeManager.int32_type) ||
 418                                     (target_type == TypeManager.int64_type) ||
 419                                     (target_type == TypeManager.double_type) ||
 420                                     (target_type == TypeManager.float_type) ||
 421                                     (target_type == TypeManager.decimal_type))
 422                                         return true;
 423
 424                         } else if (expr_type == TypeManager.ushort_type){
 425                                 //
 426                                 // From ushort to int, uint, long, ulong, float, double
 427                                 //
 428                                 if ((target_type == TypeManager.uint32_type) ||
 429                                     (target_type == TypeManager.uint64_type) ||
 430                                     (target_type == TypeManager.int32_type) ||
 431                                     (target_type == TypeManager.int64_type) ||
 432                                     (target_type == TypeManager.double_type) ||
 433                                     (target_type == TypeManager.float_type) ||
 434                                     (target_type == TypeManager.decimal_type))
 435                                         return true;
 436
 437                         } else if (expr_type == TypeManager.int32_type){
 438                                 //
 439                                 // From int to long, float, double
 440                                 //
 441                                 if ((target_type == TypeManager.int64_type) ||
 442                                     (target_type == TypeManager.double_type) ||
 443                                     (target_type == TypeManager.float_type) ||
 444                                     (target_type == TypeManager.decimal_type))
 445                                         return true;
 446
 447                         } else if (expr_type == TypeManager.uint32_type){
 448                                 //
 449                                 // From uint to long, ulong, float, double
 450                                 //
 451                                 if ((target_type == TypeManager.int64_type) ||
 452                                     (target_type == TypeManager.uint64_type) ||
 453                                     (target_type == TypeManager.double_type) ||
 454                                     (target_type == TypeManager.float_type) ||
 455                                     (target_type == TypeManager.decimal_type))
 456                                         return true;
 457
 458                         } else if ((expr_type == TypeManager.uint64_type) ||
 459                                    (expr_type == TypeManager.int64_type)) {
 460                                 //
 461                                 // From long/ulong to float, double
 462                                 //
 463                                 if ((target_type == TypeManager.double_type) ||
 464                                     (target_type == TypeManager.float_type) ||
 465                                     (target_type == TypeManager.decimal_type))
 466                                         return true;
 467
 468                         } else if (expr_type == TypeManager.char_type){
 469                                 //
 470                                 // From char to ushort, int, uint, long, ulong, float, double
 471                                 //
 472                                 if ((target_type == TypeManager.ushort_type) ||
 473                                     (target_type == TypeManager.int32_type) ||
 474                                     (target_type == TypeManager.uint32_type) ||
 475                                     (target_type == TypeManager.uint64_type) ||
 476                                     (target_type == TypeManager.int64_type) ||
 477                                     (target_type == TypeManager.float_type) ||
 478                                     (target_type == TypeManager.double_type) ||
 479                                     (target_type == TypeManager.decimal_type))
 480                                         return true;
 481
 482                         } else if (expr_type == TypeManager.float_type){
 483                                 //
 484                                 // float to double
 485                                 //
 486                                 if (target_type == TypeManager.double_type)
 487                                         return true;
 488                         }
 489
 490                         return false;
 491                 }
 492
 493                 //
 494                 // Horrible, horrible.  But there is no other way we can pass the EmitContext
 495                 // to the recursive definition triggered by the evaluation of a forward
 496                 // expression
 497                 //
 498                 static EmitContext current_ec = null;
 499
 500                 /// <summary>
 501                 ///  This is used to lookup the value of an enum member. If the member is undefined,
 502                 ///  it attempts to define it and return its value
 503                 /// </summary>
 504                 public object LookupEnumValue (EmitContext ec, string name, Location loc)
 505                 {
 506
 507                         object default_value = null;
 508                         Constant c = null;
 509
 510                         default_value = member_to_value [name];
 511
 512                         if (default_value != null)
 513                                 return default_value;
 514
 515                         //
 516                         // This may happen if we're calling a method in System.Enum, for instance
 517                         // Enum.IsDefined().
 518                         //
 519                         if (!defined_names.Contains (name))
 520                                 return null;
 521
 522                         if (in_transit.Contains (name)) {
 523                                 Report.Error (110, loc, "The evaluation of the constant value for `" +
 524                                               Name + "." + name + "' involves a circular definition.");
 525                                 return null;
 526                         }
 527
 528                         //
 529                         // So if the above doesn't happen, we have a member that is undefined
 530                         // We now proceed to define it
 531                         //
 532                         Expression val = this [name];
 533
 534                         if (val == null) {
 535
 536                                 int idx = ordered_enums.IndexOf (name);
 537
 538                                 if (idx == 0)
 539                                         default_value = 0;
 540                                 else {
 541                                         for (int i = 0; i < idx; ++i) {
 542                                                 string n = (string) ordered_enums [i];
 543                                                 Location m_loc = (Mono.CSharp.Location)
 544                                                         member_to_location [n];
 545                                                 in_transit.Add (name, true);
 546
 547                                                 EmitContext old_ec = current_ec;
 548                                                 current_ec = ec;
 549
 550                                                 default_value = LookupEnumValue (ec, n, m_loc);
 551
 552                                                 current_ec = old_ec;
 553
 554                                                 in_transit.Remove (name);
 555                                                 if (default_value == null)
 556                                                         return null;
 557                                         }
 558
 559                                         default_value = GetNextDefaultValue (default_value);
 560                                 }
 561
 562                         } else {
 563                                 bool old = ec.InEnumContext;
 564                                 ec.InEnumContext = true;
 565                                 in_transit.Add (name, true);
 566
 567                                 EmitContext old_ec = current_ec;
 568                                 current_ec = ec;
 569                                 val = val.Resolve (ec);
 570                                 current_ec = old_ec;
 571
 572                                 in_transit.Remove (name);
 573                                 ec.InEnumContext = old;
 574
 575                                 if (val == null)
 576                                         return null;
 577
 578                                 if (!IsValidEnumConstant (val)) {
 579                                         Report.Error (
 580                                                 1008, loc,
 581                                                 "Type byte, sbyte, short, ushort, int, uint, long, or " +
 582                                                 "ulong expected (have: " + val + ")");
 583                                         return null;
 584                                 }
 585
 586                                 c = (Constant) val;
 587                                 default_value = c.GetValue ();
 588
 589                                 if (default_value == null) {
 590                                         Error_ConstantValueCannotBeConverted (c, loc);
 591                                         return null;
 592                                 }
 593
 594                                 if (val is EnumConstant){
 595                                         Type etype = TypeManager.EnumToUnderlying (c.Type);
 596
 597                                         if (!ImplicitConversionExists (etype, UnderlyingType)){
 598                                                 Convert.Error_CannotImplicitConversion (
 599                                                         loc, c.Type, UnderlyingType);
 600                                                 return null;
 601                                         }
 602                                 }
 603                         }
 604
 605                         EnumMember em = name_to_member [name] as EnumMember;
 606                         em.DefineMember (TypeBuilder);
 607
 608                         bool fail;
 609                         default_value = TypeManager.ChangeType (default_value, UnderlyingType, out fail);
 610                         if (fail){
 611                                 Error_ConstantValueCannotBeConverted (c, loc);
 612                                 return null;
 613                         }
 614
 615                         em.builder.SetConstant (default_value);
 616                         field_builders.Add (em.builder);
 617                         member_to_value [name] = default_value;
 618
 619                         if (!TypeManager.RegisterFieldValue (em.builder, default_value))
 620                                 return null;
 621
 622                         return default_value;
 623                 }
 624
 625                 public override bool DefineMembers (TypeContainer parent)
 626                 {
 627                         return true;
 628                 }
 629
 630                 public override bool Define ()
 631                 {
 632                         //
 633                         // If there was an error during DefineEnum, return
 634                         //
 635                         if (TypeBuilder == null)
 636                                 return false;
 637
 638                         EmitContext ec = new EmitContext (this, this, Location, null,
 639                                                           UnderlyingType, ModFlags, false);
 640
 641
 642                         object default_value = 0;
 643
 644
 645                         foreach (string name in ordered_enums) {
 646                                 //
 647                                 // Have we already been defined, thanks to some cross-referencing ?
 648                                 //
 649                                 if (member_to_value.Contains (name))
 650                                         continue;
 651
 652                                 Location loc = (Mono.CSharp.Location) member_to_location [name];
 653
 654                                 if (this [name] != null) {
 655                                         default_value = LookupEnumValue (ec, name, loc);
 656
 657                                         if (default_value == null)
 658                                                 return true;
 659                                 } else {
 660                                         if (name == "value__"){
 661                                                 Report.Error (76, loc, "The name `value__' is reserved for enumerations");
 662                                                 return false;
 663                                         }
 664
 665                                         EnumMember em = name_to_member [name] as EnumMember;
 666
 667                                         em.DefineMember (TypeBuilder);
 668                                         FieldBuilder fb = em.builder;
 669
 670                                         if (default_value == null) {
 671                                            Report.Error (543, loc, "Enumerator value for '" + name + "' is too large to " +
 672                                                               "fit in its type");
 673                                                 return false;
 674                                         }
 675
 676                                         bool fail;
 677                                         default_value = TypeManager.ChangeType (default_value, UnderlyingType, out fail);
 678                                         if (fail){
 679                                                 Error_ConstantValueCannotBeConverted (default_value, loc);
 680                                                 return false;
 681                                         }
 682
 683                                         fb.SetConstant (default_value);
 684                                         field_builders.Add (fb);
 685                                         member_to_value [name] = default_value;
 686
 687                                         if (!TypeManager.RegisterFieldValue (fb, default_value))
 688                                                 return false;
 689                                 }
 690
 691                                 default_value = GetNextDefaultValue (default_value);
 692                         }
 693
 694                         return true;
 695                 }
 696
 697                 public override void Emit ()
 698                 {
 699                         EmitContext ec = new EmitContext (
 700                                 Parent, this, Location, null, null, ModFlags, false);
 701
 702                         if (OptAttributes != null) {
 703                                 OptAttributes.Emit (ec, this);
 704                         }
 705
 706                         foreach (EnumMember em in name_to_member.Values) {
 707                                 em.Emit (ec);
 708                         }
 709
 710                         base.Emit ();
 711                 }
 712
 713                 void VerifyClsName ()
 714                 {
 715                         Hashtable ht = new Hashtable ();
 716                         foreach (string name in ordered_enums) {
 717                                 string locase = name.ToLower (System.Globalization.CultureInfo.InvariantCulture);
 718                                 if (!ht.Contains (locase)) {
 719                                         ht.Add (locase, name_to_member [name]);
 720                                         continue;
 721                                 }
 722
 723                                 EnumMember conflict = (EnumMember)ht [locase];
 724                                 Report.SymbolRelatedToPreviousError (conflict);
 725                                 conflict = (EnumMember)name_to_member [name];
 726                                 Report.Error (3005, conflict.Location, "Identifier '{0}' differing only in case is not CLS-compliant", conflict.GetSignatureForError ());
 727                         }
 728                 }
 729
 730                 protected override bool VerifyClsCompliance (DeclSpace ds)
 731                 {
 732                         if (!base.VerifyClsCompliance (ds))
 733                                 return false;
 734
 735                         VerifyClsName ();
 736
 737                         if (!AttributeTester.IsClsCompliant (UnderlyingType)) {
 738                                 Report.Error (3009, Location, "'{0}': base type '{1}' is not CLS-compliant", GetSignatureForError (), TypeManager.CSharpName (UnderlyingType));
 739                         }
 740
 741                         return true;
 742                 }
 743
 744                 /// <summary>
 745                 /// Returns full enum name.
 746                 /// </summary>
 747                 string GetEnumeratorName (string valueName)
 748                 {
 749                         return String.Concat (Name, ".", valueName);
 750                 }
 751
 752                 //
 753                 // IMemberFinder
 754                 //
 755                 public override MemberList FindMembers (MemberTypes mt, BindingFlags bf,
 756                                                         MemberFilter filter, object criteria)
 757                 {
 758                         ArrayList members = new ArrayList ();
 759
 760                         if ((mt & MemberTypes.Field) != 0) {
 761                                 if (criteria is string){
 762                                         if (member_to_value [criteria] == null && current_ec != null){
 763                                                 LookupEnumValue (current_ec, (string) criteria, Location.Null);
 764                                         }
 765                                 }
 766
 767                                 foreach (FieldBuilder fb in field_builders)
 768                                         if (filter (fb, criteria) == true)
 769                                                 members.Add (fb);
 770                         }
 771
 772                         return new MemberList (members);
 773                 }
 774
 775                 public override MemberCache MemberCache {
 776                         get {
 777                                 return null;
 778                         }
 779                 }
 780
 781                 public ArrayList ValueNames {
 782                         get {
 783                                 return ordered_enums;
 784                         }
 785                 }
 786
 787                 // indexer
 788                 public Expression this [string name] {
 789                         get {
 790                                 return (Expression) defined_names [name];
 791                         }
 792                 }
 793
 794                 public override AttributeTargets AttributeTargets {
 795                         get {
 796                                 return AttributeTargets.Enum;
 797                         }
 798                 }
 799
 800                 protected override void VerifyObsoleteAttribute()
 801                 {
 802                         // UnderlyingType is never obsolete
 803                 }
 804
 805                 /// <summary>
 806                 /// Returns ObsoleteAttribute for both enum type and enum member
 807                 /// </summary>
 808                 public ObsoleteAttribute GetObsoleteAttribute (EmitContext ec, string identifier)
 809                 {
 810                         if ((caching_flags & Flags.Obsolete_Undetected) == 0 && (caching_flags & Flags.Obsolete) == 0) {
 811                                 return null;
 812                         }
 813
 814                         ObsoleteAttribute oa = GetObsoleteAttribute (ec.DeclSpace);
 815                         if (oa != null)
 816                                 return oa;
 817
 818                         EnumMember em = (EnumMember)name_to_member [identifier];
 819                         oa = em.GetObsoleteAttribute (ec);
 820
 821                         if (oa == null)
 822                                 return null;
 823
 824                         caching_flags |= Flags.Obsolete;
 825                         return oa;
 826                 }
 827         }
 828 }