mcs/mcs/parameter.cs

   1 //
   2 // parameter.cs: Parameter definition.
   3 //
   4 // Author: Miguel de Icaza (miguel@gnu.org)
   5 //         Marek Safar (marek.safar@seznam.cz)
   6 //
   7 // Dual licensed under the terms of the MIT X11 or GNU GPL
   8 //
   9 // Copyright 2001-2003 Ximian, Inc (http://www.ximian.com)
  10 // Copyright 2003-2008 Novell, Inc.
  11 //
  12 //
  13 using System;
  14 using System.Reflection;
  15 using System.Reflection.Emit;
  16 using System.Text;
  17 using System.Linq;
  18
  19 namespace Mono.CSharp {
  20
  21         /// <summary>
  22         ///   Abstract Base class for parameters of a method.
  23         /// </summary>
  24         public abstract class ParameterBase : Attributable
  25         {
  26                 protected ParameterBuilder builder;
  27
  28                 public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
  29                 {
  30 #if false
  31                         if (a.Type == pa.MarshalAs) {
  32                                 UnmanagedMarshal marshal = a.GetMarshal (this);
  33                                 if (marshal != null) {
  34                                         builder.SetMarshal (marshal);
  35                                 }
  36                                 return;
  37                         }
  38 #endif
  39                         if (a.HasSecurityAttribute) {
  40                                 a.Error_InvalidSecurityParent ();
  41                                 return;
  42                         }
  43
  44                         if (a.Type == pa.Dynamic) {
  45                                 a.Error_MisusedDynamicAttribute ();
  46                                 return;
  47                         }
  48
  49                         builder.SetCustomAttribute ((ConstructorInfo) ctor.GetMetaInfo (), cdata);
  50                 }
  51
  52                 public ParameterBuilder Builder {
  53                         get {
  54                                 return builder;
  55                         }
  56                 }
  57
  58                 public override bool IsClsComplianceRequired()
  59                 {
  60                         return false;
  61                 }
  62         }
  63
  64         /// <summary>
  65         /// Class for applying custom attributes on the return type
  66         /// </summary>
  67         public class ReturnParameter : ParameterBase
  68         {
  69                 MemberCore method;
  70
  71                 // TODO: merge method and mb
  72                 public ReturnParameter (MemberCore method, MethodBuilder mb, Location location)
  73                 {
  74                         this.method = method;
  75                         try {
  76                                 builder = mb.DefineParameter (0, ParameterAttributes.None, "");
  77                         }
  78                         catch (ArgumentOutOfRangeException) {
  79                                 method.Compiler.Report.RuntimeMissingSupport (location, "custom attributes on the return type");
  80                         }
  81                 }
  82
  83                 public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
  84                 {
  85                         if (a.Type == pa.CLSCompliant) {
  86                                 method.Compiler.Report.Warning (3023, 1, a.Location,
  87                                         "CLSCompliant attribute has no meaning when applied to return types. Try putting it on the method instead");
  88                         }
  89
  90                         // This occurs after Warning -28
  91                         if (builder == null)
  92                                 return;
  93
  94                         base.ApplyAttributeBuilder (a, ctor, cdata, pa);
  95                 }
  96
  97                 public override AttributeTargets AttributeTargets {
  98                         get {
  99                                 return AttributeTargets.ReturnValue;
 100                         }
 101                 }
 102
 103                 /// <summary>
 104                 /// Is never called
 105                 /// </summary>
 106                 public override string[] ValidAttributeTargets {
 107                         get {
 108                                 return null;
 109                         }
 110                 }
 111         }
 112
 113         /// <summary>
 114         /// Class for applying custom attributes on the implicit parameter type
 115         /// of the 'set' method in properties, and the 'add' and 'remove' methods in events.
 116         /// </summary>
 117         ///
 118         // TODO: should use more code from Parameter.ApplyAttributeBuilder
 119         public class ImplicitParameter : ParameterBase {
 120                 public ImplicitParameter (MethodBuilder mb)
 121                 {
 122                         builder = mb.DefineParameter (1, ParameterAttributes.None, "value");
 123                 }
 124
 125                 public override AttributeTargets AttributeTargets {
 126                         get {
 127                                 return AttributeTargets.Parameter;
 128                         }
 129                 }
 130
 131                 /// <summary>
 132                 /// Is never called
 133                 /// </summary>
 134                 public override string[] ValidAttributeTargets {
 135                         get {
 136                                 return null;
 137                         }
 138                 }
 139         }
 140
 141         public class ImplicitLambdaParameter : Parameter
 142         {
 143                 public ImplicitLambdaParameter (string name, Location loc)
 144                         : base (null, name, Modifier.NONE, null, loc)
 145                 {
 146                 }
 147
 148                 public override TypeSpec Resolve (IMemberContext ec, int index)
 149                 {
 150                         if (parameter_type == null)
 151                                 throw new InternalErrorException ("A type of implicit lambda parameter `{0}' is not set",
 152                                         Name);
 153
 154                         base.idx = index;
 155                         return parameter_type;
 156                 }
 157
 158                 public TypeSpec Type {
 159                         set { parameter_type = value; }
 160                 }
 161         }
 162
 163         public class ParamsParameter : Parameter {
 164                 public ParamsParameter (FullNamedExpression type, string name, Attributes attrs, Location loc):
 165                         base (type, name, Parameter.Modifier.PARAMS, attrs, loc)
 166                 {
 167                 }
 168
 169                 public override TypeSpec Resolve (IMemberContext ec, int index)
 170                 {
 171                         if (base.Resolve (ec, index) == null)
 172                                 return null;
 173
 174                         var ac = parameter_type as ArrayContainer;
 175                         if (ac == null || ac.Rank != 1) {
 176                                 ec.Compiler.Report.Error (225, Location, "The params parameter must be a single dimensional array");
 177                                 return null;
 178                         }
 179
 180                         return parameter_type;
 181                 }
 182
 183                 public override void ApplyAttributes (MethodBuilder mb, ConstructorBuilder cb, int index)
 184                 {
 185                         base.ApplyAttributes (mb, cb, index);
 186                         PredefinedAttributes.Get.ParamArray.EmitAttribute (builder);
 187                 }
 188         }
 189
 190         public class ArglistParameter : Parameter {
 191                 // Doesn't have proper type because it's never chosen for better conversion
 192                 public ArglistParameter (Location loc) :
 193                         base (null, String.Empty, Parameter.Modifier.NONE, null, loc)
 194                 {
 195                         parameter_type = InternalType.Arglist;
 196                 }
 197
 198                 public override void  ApplyAttributes (MethodBuilder mb, ConstructorBuilder cb, int index)
 199                 {
 200                         // Nothing to do
 201                 }
 202
 203                 public override bool CheckAccessibility (InterfaceMemberBase member)
 204                 {
 205                         return true;
 206                 }
 207
 208                 public override TypeSpec Resolve (IMemberContext ec, int index)
 209                 {
 210                         return parameter_type;
 211                 }
 212         }
 213
 214         public interface IParameterData
 215         {
 216                 Expression DefaultValue { get; }
 217                 bool HasExtensionMethodModifier { get; }
 218                 bool HasDefaultValue { get; }
 219                 Parameter.Modifier ModFlags { get; }
 220                 string Name { get; }
 221         }
 222
 223         //
 224         // Parameter information created by parser
 225         //
 226         public class Parameter : ParameterBase, IParameterData, ILocalVariable {
 227                 [Flags]
 228                 public enum Modifier : byte {
 229                         NONE    = 0,
 230                         REF     = REFMASK | ISBYREF,
 231                         OUT     = OUTMASK | ISBYREF,
 232                         PARAMS  = 4,
 233                         // This is a flag which says that it's either REF or OUT.
 234                         ISBYREF = 8,
 235                         REFMASK = 32,
 236                         OUTMASK = 64,
 237                         This    = 128
 238                 }
 239
 240                 static string[] attribute_targets = new string [] { "param" };
 241
 242                 FullNamedExpression texpr;
 243                 readonly Modifier modFlags;
 244                 string name;
 245                 Expression default_expr;
 246                 protected TypeSpec parameter_type;
 247                 public readonly Location Location;
 248                 protected int idx;
 249                 public bool HasAddressTaken;
 250
 251                 Expression expr_tree_variable;
 252                 static TypeExpr parameter_expr_tree_type;
 253
 254                 HoistedVariable hoisted_variant;
 255
 256                 public Parameter (FullNamedExpression type, string name, Modifier mod, Attributes attrs, Location loc)
 257                 {
 258                         this.name = name;
 259                         modFlags = mod;
 260                         Location = loc;
 261                         texpr = type;
 262
 263                         // Only assign, attributes will be attached during resolve
 264                         base.attributes = attrs;
 265                 }
 266
 267 #region Properties
 268                 public FullNamedExpression TypeExpression  {
 269                         get {
 270                                 return texpr;
 271                         }
 272                 }
 273 #endregion
 274
 275                 public override void ApplyAttributeBuilder (Attribute a, MethodSpec ctor, byte[] cdata, PredefinedAttributes pa)
 276                 {
 277                         if (a.Type == pa.In && ModFlags == Modifier.OUT) {
 278                                 a.Report.Error (36, a.Location, "An out parameter cannot have the `In' attribute");
 279                                 return;
 280                         }
 281
 282                         if (a.Type == pa.ParamArray) {
 283                                 a.Report.Error (674, a.Location, "Do not use `System.ParamArrayAttribute'. Use the `params' keyword instead");
 284                                 return;
 285                         }
 286
 287                         if (a.Type == PredefinedAttributes.Get.Out && (ModFlags & Modifier.REF) == Modifier.REF &&
 288                             !OptAttributes.Contains (pa.In)) {
 289                                 a.Report.Error (662, a.Location,
 290                                         "Cannot specify only `Out' attribute on a ref parameter. Use both `In' and `Out' attributes or neither");
 291                                 return;
 292                         }
 293
 294                         if (a.Type == pa.CLSCompliant) {
 295                                 a.Report.Warning (3022, 1, a.Location, "CLSCompliant attribute has no meaning when applied to parameters. Try putting it on the method instead");
 296                         }
 297
 298                         if (HasDefaultValue && (a.Type == pa.DefaultParameterValue || a.Type == pa.OptionalParameter)) {
 299                                 a.Report.Error (1745, a.Location,
 300                                         "Cannot specify `{0}' attribute on optional parameter `{1}'",
 301                                         TypeManager.CSharpName (a.Type).Replace ("Attribute", ""), Name);
 302                                 return;
 303                         }
 304
 305                         if (a.Type == pa.DefaultParameterValue) {
 306                                 TypeSpec arg_type;
 307                                 var c = a.GetParameterDefaultValue (out arg_type);
 308                                 if (c == null) {
 309                                         if (parameter_type == TypeManager.object_type) {
 310                                                 a.Report.Error (1910, a.Location, "Argument of type `{0}' is not applicable for the DefaultParameterValue attribute",
 311                                                         arg_type.GetSignatureForError ());
 312                                         } else {
 313                                                 a.Report.Error (1909, a.Location, "The DefaultParameterValue attribute is not applicable on parameters of type `{0}'",
 314                                                         parameter_type.GetSignatureForError ()); ;
 315                                         }
 316
 317                                         return;
 318                                 }
 319
 320                                 if (arg_type == parameter_type || parameter_type == TypeManager.object_type ||
 321                                         (c.IsNull && TypeManager.IsReferenceType (parameter_type) && !TypeManager.IsGenericParameter (parameter_type)))
 322                                         builder.SetConstant (c.GetValue ());
 323                                 else
 324                                         a.Report.Error (1908, a.Location, "The type of the default value should match the type of the parameter");
 325
 326                                 return;
 327                         }
 328
 329                         base.ApplyAttributeBuilder (a, ctor, cdata, pa);
 330                 }
 331
 332                 public virtual bool CheckAccessibility (InterfaceMemberBase member)
 333                 {
 334                         if (parameter_type == null || TypeManager.IsGenericParameter (parameter_type))
 335                                 return true;
 336
 337                         return member.IsAccessibleAs (parameter_type);
 338                 }
 339
 340                 public static void Reset ()
 341                 {
 342                         parameter_expr_tree_type = null;
 343                 }
 344
 345                 // <summary>
 346                 //   Resolve is used in method definitions
 347                 // </summary>
 348                 public virtual TypeSpec Resolve (IMemberContext rc, int index)
 349                 {
 350                         if (parameter_type != null)
 351                                 return parameter_type;
 352
 353                         if (attributes != null)
 354                                 attributes.AttachTo (this, rc);
 355
 356                         var expr = texpr.ResolveAsTypeTerminal (rc, false);
 357                         if (expr == null)
 358                                 return null;
 359
 360                         this.idx = index;
 361                         texpr = expr;
 362                         parameter_type = texpr.Type;
 363
 364                         if ((modFlags & Parameter.Modifier.ISBYREF) != 0 &&
 365                                 TypeManager.IsSpecialType (parameter_type)) {
 366                                 rc.Compiler.Report.Error (1601, Location, "Method or delegate parameter cannot be of type `{0}'",
 367                                         GetSignatureForError ());
 368                                 return null;
 369                         }
 370
 371                         TypeManager.CheckTypeVariance (parameter_type,
 372                                 (modFlags & Parameter.Modifier.ISBYREF) != 0 ? Variance.None : Variance.Contravariant,
 373                                 rc);
 374
 375                         if (parameter_type.IsStatic) {
 376                                 rc.Compiler.Report.Error (721, Location, "`{0}': static types cannot be used as parameters",
 377                                         texpr.GetSignatureForError ());
 378                                 return parameter_type;
 379                         }
 380
 381                         if ((modFlags & Modifier.This) != 0 && (parameter_type.IsPointer || parameter_type == InternalType.Dynamic)) {
 382                                 rc.Compiler.Report.Error (1103, Location, "The extension method cannot be of type `{0}'",
 383                                         TypeManager.CSharpName (parameter_type));
 384                         }
 385
 386                         return parameter_type;
 387                 }
 388
 389                 public void ResolveDefaultValue (ResolveContext rc)
 390                 {
 391                         if (default_expr != null)
 392                                 default_expr = ResolveDefaultExpression (rc);
 393                 }
 394
 395                 Expression ResolveDefaultExpression (ResolveContext rc)
 396                 {
 397                         default_expr = default_expr.Resolve (rc);
 398                         if (default_expr == null)
 399                                 return null;
 400
 401                         if (!(default_expr is Constant || default_expr is DefaultValueExpression)) {
 402                                 if (TypeManager.IsNullableType (parameter_type)) {
 403                                         rc.Compiler.Report.Error (1770, default_expr.Location,
 404                                                 "The expression being assigned to nullable optional parameter `{0}' must be default value",
 405                                                 Name);
 406                                 } else {
 407                                         rc.Compiler.Report.Error (1736, default_expr.Location,
 408                                                 "The expression being assigned to optional parameter `{0}' must be a constant or default value",
 409                                                 Name);
 410                                 }
 411
 412                                 return null;
 413                         }
 414
 415                         if (default_expr.Type == parameter_type)
 416                                 return default_expr;
 417
 418                         if (TypeManager.IsNullableType (parameter_type)) {
 419                                 if (Convert.ImplicitNulableConversion (rc, default_expr, parameter_type) != null)
 420                                         return default_expr;
 421                         } else {
 422                                 var res = Convert.ImplicitConversionStandard (rc, default_expr, parameter_type, default_expr.Location);
 423                                 if (res != null) {
 424                                         if (!default_expr.IsNull && TypeManager.IsReferenceType (parameter_type) && parameter_type != TypeManager.string_type) {
 425                                                 rc.Compiler.Report.Error (1763, default_expr.Location,
 426                                                         "Optional parameter `{0}' of type `{1}' can only be initialized with `null'",
 427                                                         Name, GetSignatureForError ());
 428
 429                                                 return null;
 430                                         }
 431
 432                                         return res;
 433                                 }
 434                         }
 435
 436                         rc.Compiler.Report.Error (1750, Location,
 437                                 "Optional parameter expression of type `{0}' cannot be converted to parameter type `{1}'",
 438                                 TypeManager.CSharpName (default_expr.Type), GetSignatureForError ());
 439
 440                         return null;
 441                 }
 442
 443                 public bool HasDefaultValue {
 444                         get { return default_expr != null; }
 445                 }
 446
 447                 public bool HasExtensionMethodModifier {
 448                         get { return (modFlags & Modifier.This) != 0; }
 449                 }
 450
 451                 //
 452                 // Hoisted parameter variant
 453                 //
 454                 public HoistedVariable HoistedVariant {
 455                         get {
 456                                 return hoisted_variant;
 457                         }
 458                         set {
 459                                 hoisted_variant = value;
 460                         }
 461                 }
 462
 463                 public Modifier ModFlags {
 464                         get { return modFlags & ~Modifier.This; }
 465                 }
 466
 467                 public string Name {
 468                         get { return name; }
 469                         set { name = value; }
 470                 }
 471
 472                 ParameterAttributes Attributes {
 473                         get { return ParametersCompiled.GetParameterAttribute (modFlags) |
 474                                 (HasDefaultValue ? ParameterAttributes.Optional : ParameterAttributes.None); }
 475                 }
 476
 477                 public override AttributeTargets AttributeTargets {
 478                         get {
 479                                 return AttributeTargets.Parameter;
 480                         }
 481                 }
 482
 483                 public virtual string GetSignatureForError ()
 484                 {
 485                         string type_name;
 486                         if (parameter_type != null)
 487                                 type_name = TypeManager.CSharpName (parameter_type);
 488                         else
 489                                 type_name = texpr.GetSignatureForError ();
 490
 491                         string mod = GetModifierSignature (modFlags);
 492                         if (mod.Length > 0)
 493                                 return String.Concat (mod, " ", type_name);
 494
 495                         return type_name;
 496                 }
 497
 498                 public static string GetModifierSignature (Modifier mod)
 499                 {
 500                         switch (mod) {
 501                         case Modifier.OUT:
 502                                 return "out";
 503                         case Modifier.PARAMS:
 504                                 return "params";
 505                         case Modifier.REF:
 506                                 return "ref";
 507                         case Modifier.This:
 508                                 return "this";
 509                         default:
 510                                 return "";
 511                         }
 512                 }
 513
 514                 public void IsClsCompliant (IMemberContext ctx)
 515                 {
 516                         if (parameter_type.IsCLSCompliant ())
 517                                 return;
 518
 519                         ctx.Compiler.Report.Warning (3001, 1, Location,
 520                                 "Argument type `{0}' is not CLS-compliant", GetSignatureForError ());
 521                 }
 522
 523                 public virtual void ApplyAttributes (MethodBuilder mb, ConstructorBuilder cb, int index)
 524                 {
 525                         if (mb == null)
 526                                 builder = cb.DefineParameter (index, Attributes, Name);
 527                         else
 528                                 builder = mb.DefineParameter (index, Attributes, Name);
 529
 530                         if (OptAttributes != null)
 531                                 OptAttributes.Emit ();
 532
 533                         if (HasDefaultValue) {
 534                                 //
 535                                 // Emit constant values for true constants only, the other
 536                                 // constant-like expressions will rely on default value expression
 537                                 //
 538                                 Constant c = default_expr as Constant;
 539                                 if (c != null) {
 540                                         if (default_expr.Type == TypeManager.decimal_type) {
 541                                                 builder.SetCustomAttribute (Const.CreateDecimalConstantAttribute (c));
 542                                         } else {
 543                                                 builder.SetConstant (c.GetTypedValue ());
 544                                         }
 545                                 }
 546                         }
 547
 548                         if (parameter_type == InternalType.Dynamic) {
 549                                 PredefinedAttributes.Get.Dynamic.EmitAttribute (builder);
 550                         } else {
 551                                 var trans_flags = TypeManager.HasDynamicTypeUsed (parameter_type);
 552                                 if (trans_flags != null) {
 553                                         var pa = PredefinedAttributes.Get.DynamicTransform;
 554                                         if (pa.Constructor != null || pa.ResolveConstructor (Location, ArrayContainer.MakeType (TypeManager.bool_type))) {
 555                                                 builder.SetCustomAttribute (
 556                                                         new CustomAttributeBuilder (pa.Constructor, new object [] { trans_flags }));
 557                                         }
 558                                 }
 559                         }
 560                 }
 561
 562                 public override string[] ValidAttributeTargets {
 563                         get {
 564                                 return attribute_targets;
 565                         }
 566                 }
 567
 568                 public Parameter Clone ()
 569                 {
 570                         Parameter p = (Parameter) MemberwiseClone ();
 571                         if (attributes != null)
 572                                 p.attributes = attributes.Clone ();
 573
 574                         return p;
 575                 }
 576
 577                 public ExpressionStatement CreateExpressionTreeVariable (BlockContext ec)
 578                 {
 579                         if ((modFlags & Modifier.ISBYREF) != 0)
 580                                 ec.Report.Error (1951, Location, "An expression tree parameter cannot use `ref' or `out' modifier");
 581
 582                         expr_tree_variable = new TemporaryVariable (ResolveParameterExpressionType (ec, Location).Type, Location);
 583                         expr_tree_variable = expr_tree_variable.Resolve (ec);
 584
 585                         Arguments arguments = new Arguments (2);
 586                         arguments.Add (new Argument (new TypeOf (
 587                                 new TypeExpression (parameter_type, Location), Location)));
 588                         arguments.Add (new Argument (new StringConstant (Name, Location)));
 589                         return new SimpleAssign (ExpressionTreeVariableReference (),
 590                                 Expression.CreateExpressionFactoryCall (ec, "Parameter", null, arguments, Location));
 591                 }
 592
 593                 public Expression DefaultValue {
 594                         get { return default_expr; }
 595                         set { default_expr = value; }
 596                 }
 597
 598                 public void Emit (EmitContext ec)
 599                 {
 600                         int arg_idx = idx;
 601                         if (!ec.IsStatic)
 602                                 arg_idx++;
 603
 604                         ParameterReference.EmitLdArg (ec, arg_idx);
 605                 }
 606
 607                 public void EmitAssign (EmitContext ec)
 608                 {
 609                         int arg_idx = idx;
 610                         if (!ec.IsStatic)
 611                                 arg_idx++;
 612
 613                         if (arg_idx <= 255)
 614                                 ec.Emit (OpCodes.Starg_S, (byte) arg_idx);
 615                         else
 616                                 ec.Emit (OpCodes.Starg, arg_idx);
 617                 }
 618
 619                 public void EmitAddressOf (EmitContext ec)
 620                 {
 621                         int arg_idx = idx;
 622
 623                         if (!ec.IsStatic)
 624                                 arg_idx++;
 625
 626                         bool is_ref = (ModFlags & Modifier.ISBYREF) != 0;
 627                         if (is_ref) {
 628                                 ParameterReference.EmitLdArg (ec, arg_idx);
 629                         } else {
 630                                 if (arg_idx <= 255)
 631                                         ec.Emit (OpCodes.Ldarga_S, (byte) arg_idx);
 632                                 else
 633                                         ec.Emit (OpCodes.Ldarga, arg_idx);
 634                         }
 635                 }
 636
 637                 public Expression ExpressionTreeVariableReference ()
 638                 {
 639                         return expr_tree_variable;
 640                 }
 641
 642                 //
 643                 // System.Linq.Expressions.ParameterExpression type
 644                 //
 645                 public static TypeExpr ResolveParameterExpressionType (IMemberContext ec, Location location)
 646                 {
 647                         if (parameter_expr_tree_type != null)
 648                                 return parameter_expr_tree_type;
 649
 650                         TypeSpec p_type = TypeManager.parameter_expression_type;
 651                         if (p_type == null) {
 652                                 p_type = TypeManager.CoreLookupType (ec.Compiler, "System.Linq.Expressions", "ParameterExpression", MemberKind.Class, true);
 653                                 TypeManager.parameter_expression_type = p_type;
 654                         }
 655
 656                         parameter_expr_tree_type = new TypeExpression (p_type, location).
 657                                 ResolveAsTypeTerminal (ec, false);
 658
 659                         return parameter_expr_tree_type;
 660                 }
 661
 662                 public void Warning_UselessOptionalParameter (Report Report)
 663                 {
 664                         Report.Warning (1066, 1, Location,
 665                                 "The default value specified for optional parameter `{0}' will never be used",
 666                                 Name);
 667                 }
 668         }
 669
 670         //
 671         // Imported or resolved parameter information
 672         //
 673         public class ParameterData : IParameterData
 674         {
 675                 readonly string name;
 676                 readonly Parameter.Modifier modifiers;
 677                 readonly Expression default_value;
 678
 679                 public ParameterData (string name, Parameter.Modifier modifiers)
 680                 {
 681                         this.name = name;
 682                         this.modifiers = modifiers;
 683                 }
 684
 685                 public ParameterData (string name, Parameter.Modifier modifiers, Expression defaultValue)
 686                         : this (name, modifiers)
 687                 {
 688                         this.default_value = defaultValue;
 689                 }
 690
 691                 #region IParameterData Members
 692
 693                 public Expression DefaultValue {
 694                         get { return default_value; }
 695                 }
 696
 697                 public bool HasExtensionMethodModifier {
 698                         get { return (modifiers & Parameter.Modifier.This) != 0; }
 699                 }
 700
 701                 public bool HasDefaultValue {
 702                         get { return default_value != null; }
 703                 }
 704
 705                 public Parameter.Modifier ModFlags {
 706                         get { return modifiers & ~Parameter.Modifier.This; }
 707                 }
 708
 709                 public string Name {
 710                         get { return name; }
 711                 }
 712
 713                 #endregion
 714         }
 715
 716         public abstract class AParametersCollection
 717         {
 718                 protected bool has_arglist;
 719                 protected bool has_params;
 720
 721                 // Null object pattern
 722                 protected IParameterData [] parameters;
 723                 protected TypeSpec [] types;
 724
 725                 public CallingConventions CallingConvention {
 726                         get {
 727                                 return has_arglist ?
 728                                         CallingConventions.VarArgs :
 729                                         CallingConventions.Standard;
 730                         }
 731                 }
 732
 733                 public int Count {
 734                         get { return parameters.Length; }
 735                 }
 736
 737                 public TypeSpec ExtensionMethodType {
 738                         get {
 739                                 if (Count == 0)
 740                                         return null;
 741
 742                                 return FixedParameters [0].HasExtensionMethodModifier ?
 743                                         types [0] : null;
 744                         }
 745                 }
 746
 747                 public IParameterData [] FixedParameters {
 748                         get {
 749                                 return parameters;
 750                         }
 751                 }
 752
 753                 public static ParameterAttributes GetParameterAttribute (Parameter.Modifier modFlags)
 754                 {
 755                         return (modFlags & Parameter.Modifier.OUT) == Parameter.Modifier.OUT ?
 756                                 ParameterAttributes.Out : ParameterAttributes.None;
 757                 }
 758
 759                 // Very expensive operation
 760                 public Type[] GetMetaInfo ()
 761                 {
 762                         Type[] types;
 763                         if (has_arglist) {
 764                                 if (Count == 1)
 765                                         return Type.EmptyTypes;
 766
 767                                 types = new Type [Count - 1];
 768                         } else {
 769                                 if (Count == 0)
 770                                         return Type.EmptyTypes;
 771
 772                                 types = new Type [Count];
 773                         }
 774
 775                         for (int i = 0; i < types.Length; ++i) {
 776                                 types[i] = Types[i].GetMetaInfo ();
 777
 778                                 if ((FixedParameters [i].ModFlags & Parameter.Modifier.ISBYREF) == 0)
 779                                         continue;
 780
 781                                 // TODO MemberCache: Should go to MetaInfo getter
 782                                 types [i] = types [i].MakeByRefType ();
 783                         }
 784
 785                         return types;
 786                 }
 787
 788                 //
 789                 // Returns the parameter information based on the name
 790                 //
 791                 public int GetParameterIndexByName (string name)
 792                 {
 793                         for (int idx = 0; idx < Count; ++idx) {
 794                                 if (parameters [idx].Name == name)
 795                                         return idx;
 796                         }
 797
 798                         return -1;
 799                 }
 800
 801                 public string GetSignatureForError ()
 802                 {
 803                         return GetSignatureForError ("(", ")", Count);
 804                 }
 805
 806                 public string GetSignatureForError (string start, string end, int count)
 807                 {
 808                         StringBuilder sb = new StringBuilder (start);
 809                         for (int i = 0; i < count; ++i) {
 810                                 if (i != 0)
 811                                         sb.Append (", ");
 812                                 sb.Append (ParameterDesc (i));
 813                         }
 814                         sb.Append (end);
 815                         return sb.ToString ();
 816                 }
 817
 818                 public bool HasArglist {
 819                         get { return has_arglist; }
 820                 }
 821
 822                 public bool HasExtensionMethodType {
 823                         get {
 824                                 if (Count == 0)
 825                                         return false;
 826
 827                                 return FixedParameters [0].HasExtensionMethodModifier;
 828                         }
 829                 }
 830
 831                 public bool HasParams {
 832                         get { return has_params; }
 833                 }
 834
 835                 public bool IsEmpty {
 836                         get { return parameters.Length == 0; }
 837                 }
 838
 839                 public AParametersCollection Inflate (TypeParameterInflator inflator)
 840                 {
 841                         TypeSpec[] inflated_types = null;
 842                         bool default_value = false;
 843
 844                         for (int i = 0; i < Count; ++i) {
 845                                 var inflated_param = inflator.Inflate (types[i]);
 846                                 if (inflated_types == null) {
 847                                         if (inflated_param == types[i])
 848                                                 continue;
 849
 850                                         default_value |= FixedParameters[i] is DefaultValueExpression;
 851                                         inflated_types = new TypeSpec[types.Length];
 852                                         Array.Copy (types, inflated_types, types.Length);
 853                                 }
 854
 855                                 inflated_types[i] = inflated_param;
 856                         }
 857
 858                         if (inflated_types == null)
 859                                 return this;
 860
 861                         var clone = (AParametersCollection) MemberwiseClone ();
 862                         clone.types = inflated_types;
 863                         if (default_value) {
 864                                 for (int i = 0; i < Count; ++i) {
 865                                         var dve = clone.FixedParameters[i] as DefaultValueExpression;
 866                                         if (dve != null) {
 867                                                 throw new NotImplementedException ("net");
 868                                                 //      clone.FixedParameters [i].DefaultValue = new DefaultValueExpression ();
 869                                         }
 870                                 }
 871                         }
 872
 873                         return clone;
 874                 }
 875
 876                 public string ParameterDesc (int pos)
 877                 {
 878                         if (types == null || types [pos] == null)
 879                                 return ((Parameter)FixedParameters [pos]).GetSignatureForError ();
 880
 881                         string type = TypeManager.CSharpName (types [pos]);
 882                         if (FixedParameters [pos].HasExtensionMethodModifier)
 883                                 return "this " + type;
 884
 885                         Parameter.Modifier mod = FixedParameters [pos].ModFlags;
 886                         if (mod == 0)
 887                                 return type;
 888
 889                         return Parameter.GetModifierSignature (mod) + " " + type;
 890                 }
 891
 892                 public TypeSpec[] Types {
 893                         get { return types; }
 894                         set { types = value; }
 895                 }
 896         }
 897
 898         //
 899         // A collection of imported or resolved parameters
 900         //
 901         public class ParametersImported : AParametersCollection
 902         {
 903                 ParametersImported (AParametersCollection param, TypeSpec[] types)
 904                 {
 905                         this.parameters = param.FixedParameters;
 906                         this.types = types;
 907                         has_arglist = param.HasArglist;
 908                         has_params = param.HasParams;
 909                 }
 910
 911                 ParametersImported (IParameterData [] parameters, TypeSpec [] types, bool hasArglist, bool hasParams)
 912                 {
 913                         this.parameters = parameters;
 914                         this.types = types;
 915                         this.has_arglist = hasArglist;
 916                         this.has_params = hasParams;
 917                 }
 918
 919                 public ParametersImported (IParameterData[] param, TypeSpec[] types, bool hasParams)
 920                 {
 921                         this.parameters = param;
 922                         this.types = types;
 923                         this.has_params = hasParams;
 924                 }
 925
 926                 public static AParametersCollection Create (TypeSpec parent, MethodBase method)
 927                 {
 928                         return Create (parent, method.GetParameters (), method);
 929                 }
 930
 931                 //
 932                 // Imports System.Reflection parameters
 933                 //
 934                 public static AParametersCollection Create (TypeSpec parent, ParameterInfo [] pi, MethodBase method)
 935                 {
 936                         int varargs = method != null && (method.CallingConvention & CallingConventions.VarArgs) != 0 ? 1 : 0;
 937
 938                         if (pi.Length == 0 && varargs == 0)
 939                                 return ParametersCompiled.EmptyReadOnlyParameters;
 940
 941                         TypeSpec [] types = new TypeSpec [pi.Length + varargs];
 942                         IParameterData [] par = new IParameterData [pi.Length + varargs];
 943                         bool is_params = false;
 944                         for (int i = 0; i < pi.Length; i++) {
 945                                 ParameterInfo p = pi [i];
 946                                 Parameter.Modifier mod = 0;
 947                                 Expression default_value = null;
 948                                 if (p.ParameterType.IsByRef) {
 949                                         if ((p.Attributes & (ParameterAttributes.Out | ParameterAttributes.In)) == ParameterAttributes.Out)
 950                                                 mod = Parameter.Modifier.OUT;
 951                                         else
 952                                                 mod = Parameter.Modifier.REF;
 953
 954                                         //
 955                                         // Strip reference wrapping
 956                                         //
 957                                         types [i] = Import.ImportType (p.ParameterType.GetElementType ());
 958                                 } else if (i == 0 && method.IsStatic && parent.IsStatic && // TODO: parent.Assembly.IsExtension &&
 959                                         HasExtensionAttribute (method)) {
 960                                         mod = Parameter.Modifier.This;
 961                                         types[i] = Import.ImportType (p.ParameterType);
 962                                 } else {
 963                                         types[i] = Import.ImportType (p.ParameterType);
 964
 965                                         if (i >= pi.Length - 2 && types[i] is ArrayContainer) {
 966                                                 var cattrs = CustomAttributeData.GetCustomAttributes (p);
 967                                                 if (cattrs != null && cattrs.Any (l => l.Constructor.DeclaringType == typeof (ParamArrayAttribute))) {
 968                                                         mod = Parameter.Modifier.PARAMS;
 969                                                         is_params = true;
 970                                                 }
 971                                         }
 972
 973                                         if (!is_params && p.IsOptional) {
 974                                                 object value = p.DefaultValue;
 975                                                 if (value == Missing.Value) {
 976                                                         default_value = EmptyExpression.Null;
 977                                                 } else if (value == null) {
 978                                                         default_value = new NullLiteral (Location.Null);
 979                                                 } else {
 980                                                         default_value = Constant.CreateConstant (null, Import.ImportType (value.GetType ()), value, Location.Null);
 981                                                 }
 982                                         }
 983                                 }
 984
 985                                 par [i] = new ParameterData (p.Name, mod, default_value);
 986                         }
 987
 988                         if (varargs != 0) {
 989                                 par [par.Length - 1] = new ArglistParameter (Location.Null);
 990                                 types [types.Length - 1] = InternalType.Arglist;
 991                         }
 992
 993                         return method != null ?
 994                                 new ParametersImported (par, types, varargs != 0, is_params) :
 995                                 new ParametersImported (par, types, is_params);
 996                 }
 997
 998                 static bool HasExtensionAttribute (MethodBase mb)
 999                 {
1000                         var all_attributes = CustomAttributeData.GetCustomAttributes (mb);
1001                         foreach (var attr in all_attributes) {
1002                                 var dt = attr.Constructor.DeclaringType;
1003                                 if (dt.Name == "ExtensionAttribute" && dt.Namespace == "System.Runtime.CompilerServices") {
1004                                         return true;
1005                                 }
1006                         }
1007
1008                         return false;
1009                 }
1010         }
1011
1012         /// <summary>
1013         ///   Represents the methods parameters
1014         /// </summary>
1015         public class ParametersCompiled : AParametersCollection
1016         {
1017                 public static readonly ParametersCompiled EmptyReadOnlyParameters = new ParametersCompiled ();
1018
1019                 // Used by C# 2.0 delegates
1020                 public static readonly ParametersCompiled Undefined = new ParametersCompiled ();
1021
1022                 private ParametersCompiled ()
1023                 {
1024                         parameters = new Parameter [0];
1025                         types = TypeSpec.EmptyTypes;
1026                 }
1027
1028                 private ParametersCompiled (IParameterData [] parameters, TypeSpec [] types)
1029                 {
1030                         this.parameters = parameters;
1031                     this.types = types;
1032                 }
1033
1034                 public ParametersCompiled (CompilerContext ctx, params Parameter[] parameters)
1035                 {
1036                         if (parameters == null)
1037                                 throw new ArgumentException ("Use EmptyReadOnlyParameters");
1038
1039                         this.parameters = parameters;
1040                         int count = parameters.Length;
1041
1042                         if (count == 0)
1043                                 return;
1044
1045                         if (count == 1) {
1046                                 has_params = (parameters [0].ModFlags & Parameter.Modifier.PARAMS) != 0;
1047                                 return;
1048                         }
1049
1050                         for (int i = 0; i < count; i++){
1051                                 has_params |= (parameters [i].ModFlags & Parameter.Modifier.PARAMS) != 0;
1052                                 if (ctx != null) {
1053                                         string base_name = parameters[i].Name;
1054
1055                                         for (int j = i + 1; j < count; j++) {
1056                                                 if (base_name != parameters[j].Name)
1057                                                         continue;
1058
1059                                                 ErrorDuplicateName (parameters[i], ctx.Report);
1060                                                 i = j;
1061                                         }
1062                                 }
1063                         }
1064                 }
1065
1066                 public ParametersCompiled (CompilerContext ctx, Parameter [] parameters, bool has_arglist) :
1067                         this (ctx, parameters)
1068                 {
1069                         this.has_arglist = has_arglist;
1070                 }
1071
1072                 public static ParametersCompiled CreateFullyResolved (Parameter p, TypeSpec type)
1073                 {
1074                         return new ParametersCompiled (new Parameter [] { p }, new TypeSpec [] { type });
1075                 }
1076
1077                 public static ParametersCompiled CreateFullyResolved (IParameterData[] parameters, TypeSpec[] types)
1078                 {
1079                         return new ParametersCompiled (parameters, types);
1080                 }
1081
1082                 public static AParametersCollection CreateFullyResolved (TypeSpec[] types)
1083                 {
1084                         var pd = new ParameterData [types.Length];
1085                         for (int i = 0; i < pd.Length; ++i)
1086                                 pd[i] = new ParameterData (null, Parameter.Modifier.NONE, null);
1087
1088                         return new ParametersCompiled (pd, types);
1089                 }
1090
1091                 public static ParametersCompiled CreateImplicitParameter (FullNamedExpression texpr, Location loc)
1092                 {
1093                         return new ParametersCompiled (
1094                                 new[] { new Parameter (texpr, "value", Parameter.Modifier.NONE, null, loc) },
1095                                 null);
1096                 }
1097
1098                 //
1099                 // Returns non-zero value for equal CLS parameter signatures
1100                 //
1101                 public static int IsSameClsSignature (AParametersCollection a, AParametersCollection b)
1102                 {
1103                         int res = 0;
1104
1105                         for (int i = 0; i < a.Count; ++i) {
1106                                 var a_type = a.Types[i];
1107                                 var b_type = b.Types[i];
1108                                 if (TypeSpecComparer.Override.IsEqual (a_type, b_type)) {
1109                                         const Parameter.Modifier ref_out = Parameter.Modifier.REF | Parameter.Modifier.OUT;
1110                                         if ((a.FixedParameters[i].ModFlags & ref_out) != (b.FixedParameters[i].ModFlags & ref_out))
1111                                                 res |= 1;
1112
1113                                         continue;
1114                                 }
1115
1116                                 var ac_a = a_type as ArrayContainer;
1117                                 if (ac_a == null)
1118                                         return 0;
1119
1120                                 var ac_b = b_type as ArrayContainer;
1121                                 if (ac_b == null)
1122                                         return 0;
1123
1124                                 if (ac_a.Element is ArrayContainer || ac_b.Element is ArrayContainer) {
1125                                         res |= 2;
1126                                         continue;
1127                                 }
1128
1129                                 if (ac_a.Rank != ac_b.Rank && TypeSpecComparer.Override.IsEqual (ac_a.Element, ac_b.Element)) {
1130                                         res |= 1;
1131                                         continue;
1132                                 }
1133
1134                                 return 0;
1135                         }
1136
1137                         return res;
1138                 }
1139
1140                 public static ParametersCompiled MergeGenerated (CompilerContext ctx, ParametersCompiled userParams, bool checkConflicts, Parameter compilerParams, TypeSpec compilerTypes)
1141                 {
1142                         return MergeGenerated (ctx, userParams, checkConflicts,
1143                                 new Parameter [] { compilerParams },
1144                                 new TypeSpec [] { compilerTypes });
1145                 }
1146
1147                 //
1148                 // Use this method when you merge compiler generated parameters with user parameters
1149                 //
1150                 public static ParametersCompiled MergeGenerated (CompilerContext ctx, ParametersCompiled userParams, bool checkConflicts, Parameter[] compilerParams, TypeSpec[] compilerTypes)
1151                 {
1152                         Parameter[] all_params = new Parameter [userParams.Count + compilerParams.Length];
1153                         userParams.FixedParameters.CopyTo(all_params, 0);
1154
1155                         TypeSpec [] all_types;
1156                         if (userParams.types != null) {
1157                                 all_types = new TypeSpec [all_params.Length];
1158                                 userParams.Types.CopyTo (all_types, 0);
1159                         } else {
1160                                 all_types = null;
1161                         }
1162
1163                         int last_filled = userParams.Count;
1164                         int index = 0;
1165                         foreach (Parameter p in compilerParams) {
1166                                 for (int i = 0; i < last_filled; ++i) {
1167                                         while (p.Name == all_params [i].Name) {
1168                                                 if (checkConflicts && i < userParams.Count) {
1169                                                         ctx.Report.Error (316, userParams[i].Location,
1170                                                                 "The parameter name `{0}' conflicts with a compiler generated name", p.Name);
1171                                                 }
1172                                                 p.Name = '_' + p.Name;
1173                                         }
1174                                 }
1175                                 all_params [last_filled] = p;
1176                                 if (all_types != null)
1177                                         all_types [last_filled] = compilerTypes [index++];
1178                                 ++last_filled;
1179                         }
1180
1181                         ParametersCompiled parameters = new ParametersCompiled (all_params, all_types);
1182                         parameters.has_params = userParams.has_params;
1183                         return parameters;
1184                 }
1185
1186                 protected virtual void ErrorDuplicateName (Parameter p, Report Report)
1187                 {
1188                         Report.Error (100, p.Location, "The parameter name `{0}' is a duplicate", p.Name);
1189                 }
1190
1191                 public bool Resolve (IMemberContext ec)
1192                 {
1193                         if (types != null)
1194                                 return true;
1195
1196                         types = new TypeSpec [Count];
1197
1198                         bool ok = true;
1199                         Parameter p;
1200                         for (int i = 0; i < FixedParameters.Length; ++i) {
1201                                 p = this [i];
1202                                 TypeSpec t = p.Resolve (ec, i);
1203                                 if (t == null) {
1204                                         ok = false;
1205                                         continue;
1206                                 }
1207
1208                                 types [i] = t;
1209                         }
1210
1211                         return ok;
1212                 }
1213
1214                 public void ResolveDefaultValues (ResolveContext rc)
1215                 {
1216                         for (int i = 0; i < FixedParameters.Length; ++i) {
1217                                 this [i].ResolveDefaultValue (rc);
1218                         }
1219                 }
1220
1221                 // Define each type attribute (in/out/ref) and
1222                 // the argument names.
1223                 public void ApplyAttributes (MethodBase builder)
1224                 {
1225                         if (Count == 0)
1226                                 return;
1227
1228                         MethodBuilder mb = builder as MethodBuilder;
1229                         ConstructorBuilder cb = builder as ConstructorBuilder;
1230
1231                         for (int i = 0; i < Count; i++) {
1232                                 this [i].ApplyAttributes (mb, cb, i + 1);
1233                         }
1234                 }
1235
1236                 public void VerifyClsCompliance (IMemberContext ctx)
1237                 {
1238                         foreach (Parameter p in FixedParameters)
1239                                 p.IsClsCompliant (ctx);
1240                 }
1241
1242                 public Parameter this [int pos] {
1243                         get { return (Parameter) parameters [pos]; }
1244                 }
1245
1246                 public Expression CreateExpressionTree (BlockContext ec, Location loc)
1247                 {
1248                         var initializers = new ArrayInitializer (Count, loc);
1249                         foreach (Parameter p in FixedParameters) {
1250                                 //
1251                                 // Each parameter expression is stored to local variable
1252                                 // to save some memory when referenced later.
1253                                 //
1254                                 StatementExpression se = new StatementExpression (p.CreateExpressionTreeVariable (ec));
1255                                 if (se.Resolve (ec))
1256                                         ec.CurrentBlock.AddScopeStatement (se);
1257
1258                                 initializers.Add (p.ExpressionTreeVariableReference ());
1259                         }
1260
1261                         return new ArrayCreation (
1262                                 Parameter.ResolveParameterExpressionType (ec, loc),
1263                                 initializers, loc);
1264                 }
1265
1266                 public ParametersCompiled Clone ()
1267                 {
1268                         ParametersCompiled p = (ParametersCompiled) MemberwiseClone ();
1269
1270                         p.parameters = new IParameterData [parameters.Length];
1271                         for (int i = 0; i < Count; ++i)
1272                                 p.parameters [i] = this [i].Clone ();
1273
1274                         return p;
1275                 }
1276         }
1277 }