mcs/mcs/delegate.cs

   1 //
   2 // delegate.cs: Delegate Handler
   3 //
   4 // Authors:
   5 //     Ravi Pratap (ravi@ximian.com)
   6 //     Miguel de Icaza (miguel@ximian.com)
   7 //     Marek Safar (marek.safar@gmail.com)
   8 //
   9 // Dual licensed under the terms of the MIT X11 or GNU GPL
  10 //
  11 // Copyright 2001 Ximian, Inc (http://www.ximian.com)
  12 // Copyright 2003-2008 Novell, Inc (http://www.ximian.com)
  13 //
  14
  15 using System;
  16 using System.Collections;
  17 using System.Reflection;
  18 using System.Reflection.Emit;
  19 using System.Text;
  20
  21 namespace Mono.CSharp {
  22
  23         /// <summary>
  24         ///   Holds Delegates
  25         /// </summary>
  26         public class Delegate : DeclSpace, IMemberContainer
  27         {
  28                 FullNamedExpression ReturnType;
  29                 public ParametersCompiled      Parameters;
  30
  31                 public ConstructorBuilder ConstructorBuilder;
  32                 public MethodBuilder      InvokeBuilder;
  33                 public MethodBuilder      BeginInvokeBuilder;
  34                 public MethodBuilder      EndInvokeBuilder;
  35
  36                 Type ret_type;
  37
  38                 static string[] attribute_targets = new string [] { "type", "return" };
  39
  40                 Expression instance_expr;
  41                 MethodBase delegate_method;
  42                 ReturnParameter return_attributes;
  43
  44                 MemberCache member_cache;
  45
  46                 const MethodAttributes mattr = MethodAttributes.Public | MethodAttributes.HideBySig |
  47                         MethodAttributes.Virtual | MethodAttributes.NewSlot;
  48
  49                 const int AllowedModifiers =
  50                         Modifiers.NEW |
  51                         Modifiers.PUBLIC |
  52                         Modifiers.PROTECTED |
  53                         Modifiers.INTERNAL |
  54                         Modifiers.UNSAFE |
  55                         Modifiers.PRIVATE;
  56
  57                 public Delegate (NamespaceEntry ns, DeclSpace parent, FullNamedExpression type,
  58                                  int mod_flags, MemberName name, ParametersCompiled param_list,
  59                                  Attributes attrs)
  60                         : base (ns, parent, name, attrs)
  61
  62                 {
  63                         this.ReturnType = type;
  64                         ModFlags        = Modifiers.Check (AllowedModifiers, mod_flags,
  65                                                            IsTopLevel ? Modifiers.INTERNAL :
  66                                                            Modifiers.PRIVATE, name.Location);
  67                         Parameters      = param_list;
  68                 }
  69
  70                 public override void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder cb, PredefinedAttributes pa)
  71                 {
  72                         if (a.Target == AttributeTargets.ReturnValue) {
  73                                 if (return_attributes == null)
  74                                         return_attributes = new ReturnParameter (InvokeBuilder, Location);
  75
  76                                 return_attributes.ApplyAttributeBuilder (a, cb, pa);
  77                                 return;
  78                         }
  79
  80                         base.ApplyAttributeBuilder (a, cb, pa);
  81                 }
  82
  83                 public override TypeBuilder DefineType ()
  84                 {
  85                         if (TypeBuilder != null)
  86                                 return TypeBuilder;
  87
  88                         if (IsTopLevel) {
  89                                 if (TypeManager.NamespaceClash (Name, Location))
  90                                         return null;
  91
  92                                 ModuleBuilder builder = Module.Builder;
  93
  94                                 TypeBuilder = builder.DefineType (
  95                                         Name, TypeAttr, TypeManager.multicast_delegate_type);
  96                         } else {
  97                                 TypeBuilder builder = Parent.TypeBuilder;
  98
  99                                 string name = Name.Substring (1 + Name.LastIndexOf ('.'));
 100                                 TypeBuilder = builder.DefineNestedType (
 101                                         name, TypeAttr, TypeManager.multicast_delegate_type);
 102                         }
 103
 104                         TypeManager.AddUserType (this);
 105
 106 #if GMCS_SOURCE
 107                         if (IsGeneric) {
 108                                 string[] param_names = new string [TypeParameters.Length];
 109                                 for (int i = 0; i < TypeParameters.Length; i++)
 110                                         param_names [i] = TypeParameters [i].Name;
 111
 112                                 GenericTypeParameterBuilder[] gen_params;
 113                                 gen_params = TypeBuilder.DefineGenericParameters (param_names);
 114
 115                                 int offset = CountTypeParameters - CurrentTypeParameters.Length;
 116                                 for (int i = offset; i < gen_params.Length; i++)
 117                                         CurrentTypeParameters [i - offset].Define (gen_params [i]);
 118
 119                                 foreach (TypeParameter type_param in CurrentTypeParameters) {
 120                                         if (!type_param.Resolve (this))
 121                                                 return null;
 122                                 }
 123
 124                                 Expression current = new SimpleName (
 125                                         MemberName.Basename, TypeParameters, Location);
 126                                 current = current.ResolveAsTypeTerminal (this, false);
 127                                 if (current == null)
 128                                         return null;
 129
 130                                 CurrentType = current.Type;
 131                         }
 132 #endif
 133
 134                         return TypeBuilder;
 135                 }
 136
 137                 public override bool Define ()
 138                 {
 139                         if (IsGeneric) {
 140                                 foreach (TypeParameter type_param in TypeParameters) {
 141                                         if (!type_param.Resolve (this))
 142                                                 return false;
 143                                 }
 144
 145                                 foreach (TypeParameter type_param in TypeParameters) {
 146                                         if (!type_param.DefineType (this))
 147                                                 return false;
 148                                 }
 149                         }
 150
 151                         member_cache = new MemberCache (TypeManager.multicast_delegate_type, this);
 152
 153                         // FIXME: POSSIBLY make this static, as it is always constant
 154                         //
 155                         Type [] const_arg_types = new Type [2];
 156                         const_arg_types [0] = TypeManager.object_type;
 157                         const_arg_types [1] = TypeManager.intptr_type;
 158
 159                         const MethodAttributes ctor_mattr = MethodAttributes.RTSpecialName | MethodAttributes.SpecialName |
 160                                 MethodAttributes.HideBySig | MethodAttributes.Public;
 161
 162                         ConstructorBuilder = TypeBuilder.DefineConstructor (ctor_mattr,
 163                                                                             CallingConventions.Standard,
 164                                                                             const_arg_types);
 165
 166                         ConstructorBuilder.DefineParameter (1, ParameterAttributes.None, "object");
 167                         ConstructorBuilder.DefineParameter (2, ParameterAttributes.None, "method");
 168                         //
 169                         // HACK because System.Reflection.Emit is lame
 170                         //
 171                         IParameterData [] fixed_pars = new IParameterData [] {
 172                                 new ParameterData ("object", Parameter.Modifier.NONE),
 173                                 new ParameterData ("method", Parameter.Modifier.NONE)
 174                         };
 175
 176                         AParametersCollection const_parameters = new ParametersImported (
 177                                 fixed_pars,
 178                                 new Type[] { TypeManager.object_type, TypeManager.intptr_type });
 179
 180                         TypeManager.RegisterMethod (ConstructorBuilder, const_parameters);
 181                         member_cache.AddMember (ConstructorBuilder, this);
 182
 183                         ConstructorBuilder.SetImplementationFlags (MethodImplAttributes.Runtime);
 184
 185                         //
 186                         // Here the various methods like Invoke, BeginInvoke etc are defined
 187                         //
 188                         // First, call the `out of band' special method for
 189                         // defining recursively any types we need:
 190
 191                         if (!Parameters.Resolve (this))
 192                                 return false;
 193
 194                         //
 195                         // Invoke method
 196                         //
 197
 198                         // Check accessibility
 199                         foreach (Type partype in Parameters.Types){
 200                                 if (!IsAccessibleAs (partype)) {
 201                                         Report.SymbolRelatedToPreviousError (partype);
 202                                         Report.Error (59, Location,
 203                                                       "Inconsistent accessibility: parameter type `{0}' is less accessible than delegate `{1}'",
 204                                                       TypeManager.CSharpName (partype),
 205                                                       GetSignatureForError ());
 206                                         return false;
 207                                 }
 208                         }
 209
 210                         ReturnType = ReturnType.ResolveAsTypeTerminal (this, false);
 211                         if (ReturnType == null)
 212                                 return false;
 213
 214                         ret_type = ReturnType.Type;
 215
 216                         if (!IsAccessibleAs (ret_type)) {
 217                                 Report.SymbolRelatedToPreviousError (ret_type);
 218                                 Report.Error (58, Location,
 219                                               "Inconsistent accessibility: return type `" +
 220                                               TypeManager.CSharpName (ret_type) + "' is less " +
 221                                               "accessible than delegate `" + GetSignatureForError () + "'");
 222                                 return false;
 223                         }
 224
 225                         CheckProtectedModifier ();
 226
 227                         if (RootContext.StdLib && TypeManager.IsSpecialType (ret_type)) {
 228                                 Method.Error1599 (Location, ret_type);
 229                                 return false;
 230                         }
 231
 232                         var tp = TypeManager.LookupTypeParameter (ret_type);
 233                         if (tp != null && tp.Variance == Variance.Contravariant)
 234                                 tp.ErrorInvalidVariance (this, Variance.Covariant);
 235
 236                         //
 237                         // We don't have to check any others because they are all
 238                         // guaranteed to be accessible - they are standard types.
 239                         //
 240
 241                         CallingConventions cc = Parameters.CallingConvention;
 242
 243                         InvokeBuilder = TypeBuilder.DefineMethod ("Invoke",
 244                                                                   mattr,
 245                                                                   cc,
 246                                                                   ret_type,
 247                                                                   Parameters.GetEmitTypes ());
 248
 249                         InvokeBuilder.SetImplementationFlags (MethodImplAttributes.Runtime);
 250
 251                         TypeManager.RegisterMethod (InvokeBuilder, Parameters);
 252                         member_cache.AddMember (InvokeBuilder, this);
 253
 254                         if (TypeManager.iasyncresult_type != null && TypeManager.asynccallback_type != null) {
 255                                 DefineAsyncMethods (cc);
 256                         }
 257
 258                         return true;
 259                 }
 260
 261                 void DefineAsyncMethods (CallingConventions cc)
 262                 {
 263                         //
 264                         // BeginInvoke
 265                         //
 266                         ParametersCompiled async_parameters = ParametersCompiled.MergeGenerated (Parameters, false,
 267                                 new Parameter [] {
 268                                         new Parameter (null, "callback", Parameter.Modifier.NONE, null, Location),
 269                                         new Parameter (null, "object", Parameter.Modifier.NONE, null, Location)
 270                                 },
 271                                 new Type [] {
 272                                         TypeManager.asynccallback_type,
 273                                         TypeManager.object_type
 274                                 }
 275                         );
 276
 277                         BeginInvokeBuilder = TypeBuilder.DefineMethod ("BeginInvoke",
 278                                 mattr, cc, TypeManager.iasyncresult_type, async_parameters.GetEmitTypes ());
 279
 280                         BeginInvokeBuilder.SetImplementationFlags (MethodImplAttributes.Runtime);
 281                         TypeManager.RegisterMethod (BeginInvokeBuilder, async_parameters);
 282                         member_cache.AddMember (BeginInvokeBuilder, this);
 283
 284                         //
 285                         // EndInvoke is a bit more interesting, all the parameters labeled as
 286                         // out or ref have to be duplicated here.
 287                         //
 288
 289                         //
 290                         // Define parameters, and count out/ref parameters
 291                         //
 292                         ParametersCompiled end_parameters;
 293                         int out_params = 0;
 294
 295                         foreach (Parameter p in Parameters.FixedParameters) {
 296                                 if ((p.ModFlags & Parameter.Modifier.ISBYREF) != 0)
 297                                         ++out_params;
 298                         }
 299
 300                         if (out_params > 0) {
 301                                 Type [] end_param_types = new Type [out_params];
 302                                 Parameter[] end_params = new Parameter [out_params];
 303
 304                                 int param = 0;
 305                                 for (int i = 0; i < Parameters.FixedParameters.Length; ++i) {
 306                                         Parameter p = Parameters [i];
 307                                         if ((p.ModFlags & Parameter.Modifier.ISBYREF) == 0)
 308                                                 continue;
 309
 310                                         end_param_types [param] = Parameters.Types [i];
 311                                         end_params [param] = p;
 312                                         ++param;
 313                                 }
 314                                 end_parameters = ParametersCompiled.CreateFullyResolved (end_params, end_param_types);
 315                         } else {
 316                                 end_parameters = ParametersCompiled.EmptyReadOnlyParameters;
 317                         }
 318
 319                         end_parameters = ParametersCompiled.MergeGenerated (end_parameters, false,
 320                                 new Parameter (null, "result", Parameter.Modifier.NONE, null, Location), TypeManager.iasyncresult_type);
 321
 322                         //
 323                         // Create method, define parameters, register parameters with type system
 324                         //
 325                         EndInvokeBuilder = TypeBuilder.DefineMethod ("EndInvoke", mattr, cc, ret_type, end_parameters.GetEmitTypes ());
 326                         EndInvokeBuilder.SetImplementationFlags (MethodImplAttributes.Runtime);
 327
 328                         end_parameters.ApplyAttributes (EndInvokeBuilder);
 329                         TypeManager.RegisterMethod (EndInvokeBuilder, end_parameters);
 330                         member_cache.AddMember (EndInvokeBuilder, this);
 331                 }
 332
 333                 public override void Emit ()
 334                 {
 335                         Parameters.ApplyAttributes (InvokeBuilder);
 336
 337                         if (BeginInvokeBuilder != null) {
 338                                 ParametersCompiled p = (ParametersCompiled) TypeManager.GetParameterData (BeginInvokeBuilder);
 339                                 p.ApplyAttributes (BeginInvokeBuilder);
 340                         }
 341
 342                         if (OptAttributes != null) {
 343                                 OptAttributes.Emit ();
 344                         }
 345
 346                         base.Emit ();
 347                 }
 348
 349                 protected override TypeAttributes TypeAttr {
 350                         get {
 351                                 return Modifiers.TypeAttr (ModFlags, IsTopLevel) |
 352                                         TypeAttributes.Class | TypeAttributes.Sealed |
 353                                         base.TypeAttr;
 354                         }
 355                 }
 356
 357                 public override string[] ValidAttributeTargets {
 358                         get {
 359                                 return attribute_targets;
 360                         }
 361                 }
 362
 363                 //TODO: duplicate
 364                 protected override bool VerifyClsCompliance ()
 365                 {
 366                         if (!base.VerifyClsCompliance ()) {
 367                                 return false;
 368                         }
 369
 370                         Parameters.VerifyClsCompliance ();
 371
 372                         if (!AttributeTester.IsClsCompliant (ReturnType.Type)) {
 373                                 Report.Warning (3002, 1, Location, "Return type of `{0}' is not CLS-compliant",
 374                                         GetSignatureForError ());
 375                         }
 376                         return true;
 377                 }
 378
 379
 380                 public static ConstructorInfo GetConstructor (Type container_type, Type delegate_type)
 381                 {
 382                         Type dt = delegate_type;
 383                         Type[] g_args = null;
 384                         if (TypeManager.IsGenericType (delegate_type)) {
 385                                 g_args = TypeManager.GetTypeArguments (delegate_type);
 386                                 delegate_type = TypeManager.DropGenericTypeArguments (delegate_type);
 387                         }
 388
 389                         Delegate d = TypeManager.LookupDelegate (delegate_type);
 390                         if (d != null) {
 391 #if GMCS_SOURCE
 392                                 if (g_args != null)
 393                                         return TypeBuilder.GetConstructor (dt, d.ConstructorBuilder);
 394 #endif
 395                                 return d.ConstructorBuilder;
 396                         }
 397
 398                         Expression ml = Expression.MemberLookup (container_type,
 399                                 null, dt, ConstructorInfo.ConstructorName, MemberTypes.Constructor,
 400                                 BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly, Location.Null);
 401
 402                         MethodGroupExpr mg = ml as MethodGroupExpr;
 403                         if (mg == null) {
 404                                 Report.Error (-100, Location.Null, "Internal error: could not find delegate constructor!");
 405                                 // FIXME: null will cause a crash later
 406                                 return null;
 407                         }
 408
 409                         return (ConstructorInfo) mg.Methods[0];
 410                 }
 411
 412                 //
 413                 // Returns the MethodBase for "Invoke" from a delegate type, this is used
 414                 // to extract the signature of a delegate.
 415                 //
 416                 public static MethodInfo GetInvokeMethod (Type container_type, Type delegate_type)
 417                 {
 418                         Type dt = delegate_type;
 419
 420                         Type[] g_args = null;
 421                         if (TypeManager.IsGenericType (delegate_type)) {
 422                                 g_args = TypeManager.GetTypeArguments (delegate_type);
 423                                 delegate_type = TypeManager.DropGenericTypeArguments (delegate_type);
 424                         }
 425
 426                         Delegate d = TypeManager.LookupDelegate (delegate_type);
 427                         MethodInfo invoke;
 428                         if (d != null) {
 429 #if GMCS_SOURCE
 430                                 if (g_args != null) {
 431                                         invoke = TypeBuilder.GetMethod (dt, d.InvokeBuilder);
 432 #if MS_COMPATIBLE
 433                                         ParametersCompiled p = (ParametersCompiled) d.Parameters.InflateTypes (g_args, g_args);
 434                                         TypeManager.RegisterMethod (invoke, p);
 435 #endif
 436                                         return invoke;
 437                                 }
 438 #endif
 439                                 return d.InvokeBuilder;
 440                         }
 441
 442                         Expression ml = Expression.MemberLookup (container_type, null, dt,
 443                                 "Invoke", Location.Null);
 444
 445                         MethodGroupExpr mg = ml as MethodGroupExpr;
 446                         if (mg == null) {
 447                                 Report.Error (-100, Location.Null, "Internal error: could not find Invoke method!");
 448                                 // FIXME: null will cause a crash later
 449                                 return null;
 450                         }
 451
 452                         invoke = (MethodInfo) mg.Methods[0];
 453 #if MS_COMPATIBLE
 454                         if (g_args != null) {
 455                                 AParametersCollection p = TypeManager.GetParameterData (invoke);
 456                                 p = p.InflateTypes (g_args, g_args);
 457                                 TypeManager.RegisterMethod (invoke, p);
 458                                 return invoke;
 459                         }
 460 #endif
 461
 462                         return invoke;
 463                 }
 464
 465                 //
 466                 // 15.2 Delegate compatibility
 467                 //
 468                 public static bool IsTypeCovariant (Expression a, Type b)
 469                 {
 470                         //
 471                         // For each value parameter (a parameter with no ref or out modifier), an
 472                         // identity conversion or implicit reference conversion exists from the
 473                         // parameter type in D to the corresponding parameter type in M
 474                         //
 475                         if (a.Type == b)
 476                                 return true;
 477
 478                         if (RootContext.Version == LanguageVersion.ISO_1)
 479                                 return false;
 480
 481                         return Convert.ImplicitReferenceConversionExists (a, b);
 482                 }
 483
 484                 /// <summary>
 485                 ///  Verifies whether the method in question is compatible with the delegate
 486                 ///  Returns the method itself if okay and null if not.
 487                 /// </summary>
 488                 public static MethodBase VerifyMethod (Type container_type, Type delegate_type,
 489                                                        MethodGroupExpr old_mg, MethodBase mb)
 490                 {
 491                         bool is_method_definition = TypeManager.IsGenericMethodDefinition (mb);
 492
 493                         MethodInfo invoke_mb = GetInvokeMethod (container_type, delegate_type);
 494                         if (invoke_mb == null)
 495                                 return null;
 496
 497                         if (is_method_definition)
 498                                 invoke_mb = (MethodInfo) TypeManager.DropGenericMethodArguments (invoke_mb);
 499
 500                         AParametersCollection invoke_pd = TypeManager.GetParameterData (invoke_mb);
 501
 502 #if GMCS_SOURCE
 503                         if (!is_method_definition && old_mg.type_arguments == null &&
 504                             !TypeManager.InferTypeArguments (invoke_pd, ref mb))
 505                                 return null;
 506 #endif
 507                         AParametersCollection pd = TypeManager.GetParameterData (mb);
 508
 509                         if (invoke_pd.Count != pd.Count)
 510                                 return null;
 511
 512                         for (int i = pd.Count; i > 0; ) {
 513                                 i--;
 514
 515                                 Type invoke_pd_type = invoke_pd.Types [i];
 516                                 Type pd_type = pd.Types [i];
 517                                 Parameter.Modifier invoke_pd_type_mod = invoke_pd.FixedParameters [i].ModFlags;
 518                                 Parameter.Modifier pd_type_mod = pd.FixedParameters [i].ModFlags;
 519
 520                                 invoke_pd_type_mod &= ~Parameter.Modifier.PARAMS;
 521                                 pd_type_mod &= ~Parameter.Modifier.PARAMS;
 522
 523                                 if (invoke_pd_type_mod != pd_type_mod)
 524                                         return null;
 525
 526                                 if (TypeManager.IsEqual (invoke_pd_type, pd_type))
 527                                         continue;
 528
 529                                 if (IsTypeCovariant (new EmptyExpression (invoke_pd_type), pd_type))
 530                                         continue;
 531
 532                                 return null;
 533                         }
 534
 535                         Type invoke_mb_retval = ((MethodInfo) invoke_mb).ReturnType;
 536                         Type mb_retval = ((MethodInfo) mb).ReturnType;
 537                         if (TypeManager.TypeToCoreType (invoke_mb_retval) == TypeManager.TypeToCoreType (mb_retval))
 538                                 return mb;
 539
 540                         //if (!IsTypeCovariant (mb_retval, invoke_mb_retval))
 541                         //      return null;
 542
 543                         if (RootContext.Version == LanguageVersion.ISO_1)
 544                                 return null;
 545
 546                         return mb;
 547                 }
 548
 549                 // <summary>
 550                 //  Verifies whether the invocation arguments are compatible with the
 551                 //  delegate's target method
 552                 // </summary>
 553                 public static bool VerifyApplicability (EmitContext ec, Type delegate_type,
 554                                                         ArrayList args, Location loc)
 555                 {
 556                         int arg_count;
 557
 558                         if (args == null)
 559                                 arg_count = 0;
 560                         else
 561                                 arg_count = args.Count;
 562
 563                         MethodBase mb = GetInvokeMethod (ec.ContainerType, delegate_type);
 564                         MethodGroupExpr me = new MethodGroupExpr (new MemberInfo [] { mb }, delegate_type, loc);
 565
 566                         AParametersCollection pd = TypeManager.GetParameterData (mb);
 567
 568                         int pd_count = pd.Count;
 569
 570                         bool params_method = pd.HasParams;
 571                         bool is_params_applicable = false;
 572                         bool is_applicable = me.IsApplicable (ec, args, arg_count, ref mb, ref is_params_applicable) == 0;
 573
 574                         if (!is_applicable && !params_method && arg_count != pd_count) {
 575                                 Report.Error (1593, loc, "Delegate `{0}' does not take `{1}' arguments",
 576                                         TypeManager.CSharpName (delegate_type), arg_count.ToString ());
 577                                 return false;
 578                         }
 579
 580                         return me.VerifyArgumentsCompat (
 581                                         ec, ref args, arg_count, mb,
 582                                         is_params_applicable || (!is_applicable && params_method),
 583                                         false, loc);
 584                 }
 585
 586                 public static string FullDelegateDesc (MethodBase invoke_method)
 587                 {
 588                         return TypeManager.GetFullNameSignature (invoke_method).Replace (".Invoke", "");
 589                 }
 590
 591                 public override MemberCache MemberCache {
 592                         get {
 593                                 return member_cache;
 594                         }
 595                 }
 596
 597                 public Expression InstanceExpression {
 598                         get {
 599                                 return instance_expr;
 600                         }
 601                         set {
 602                                 instance_expr = value;
 603                         }
 604                 }
 605
 606                 public MethodBase TargetMethod {
 607                         get {
 608                                 return delegate_method;
 609                         }
 610                         set {
 611                                 delegate_method = value;
 612                         }
 613                 }
 614
 615                 public Type TargetReturnType {
 616                         get {
 617                                 return ret_type;
 618                         }
 619                 }
 620
 621                 public override AttributeTargets AttributeTargets {
 622                         get {
 623                                 return AttributeTargets.Delegate;
 624                         }
 625                 }
 626
 627                 //
 628                 //   Represents header string for documentation comment.
 629                 //
 630                 public override string DocCommentHeader {
 631                         get { return "T:"; }
 632                 }
 633
 634                 #region IMemberContainer Members
 635
 636                 string IMemberContainer.Name
 637                 {
 638                         get { throw new NotImplementedException (); }
 639                 }
 640
 641                 Type IMemberContainer.Type
 642                 {
 643                         get { throw new NotImplementedException (); }
 644                 }
 645
 646                 MemberCache IMemberContainer.BaseCache
 647                 {
 648                         get { throw new NotImplementedException (); }
 649                 }
 650
 651                 bool IMemberContainer.IsInterface {
 652                         get {
 653                                 return false;
 654                         }
 655                 }
 656
 657                 MemberList IMemberContainer.GetMembers (MemberTypes mt, BindingFlags bf)
 658                 {
 659                         throw new NotImplementedException ();
 660                 }
 661
 662                 #endregion
 663         }
 664
 665         //
 666         // Base class for `NewDelegate' and `ImplicitDelegateCreation'
 667         //
 668         public abstract class DelegateCreation : Expression, MethodGroupExpr.IErrorHandler
 669         {
 670                 protected ConstructorInfo constructor_method;
 671                 protected MethodInfo delegate_method;
 672                 // We keep this to handle IsBase only
 673                 protected MethodGroupExpr method_group;
 674                 protected Expression delegate_instance_expression;
 675
 676                 public static ArrayList CreateDelegateMethodArguments (MethodInfo invoke_method, Location loc)
 677                 {
 678                         AParametersCollection pd = TypeManager.GetParameterData (invoke_method);
 679                         ArrayList delegate_arguments = new ArrayList (pd.Count);
 680                         for (int i = 0; i < pd.Count; ++i) {
 681                                 Argument.AType atype_modifier;
 682                                 Type atype = pd.Types [i];
 683                                 switch (pd.FixedParameters [i].ModFlags) {
 684                                 case Parameter.Modifier.REF:
 685                                         atype_modifier = Argument.AType.Ref;
 686                                         //atype = atype.GetElementType ();
 687                                         break;
 688                                 case Parameter.Modifier.OUT:
 689                                         atype_modifier = Argument.AType.Out;
 690                                         //atype = atype.GetElementType ();
 691                                         break;
 692                                 case Parameter.Modifier.ARGLIST:
 693                                         // __arglist is not valid
 694                                         throw new InternalErrorException ("__arglist modifier");
 695                                 default:
 696                                         atype_modifier = Argument.AType.Expression;
 697                                         break;
 698                                 }
 699                                 delegate_arguments.Add (new Argument (new TypeExpression (atype, loc), atype_modifier));
 700                         }
 701                         return delegate_arguments;
 702                 }
 703
 704                 public override Expression CreateExpressionTree (EmitContext ec)
 705                 {
 706                         MemberAccess ma = new MemberAccess (new MemberAccess (new QualifiedAliasMember ("global", "System", loc), "Delegate", loc), "CreateDelegate", loc);
 707
 708                         ArrayList args = new ArrayList (3);
 709                         args.Add (new Argument (new TypeOf (new TypeExpression (type, loc), loc)));
 710                         args.Add (new Argument (new NullLiteral (loc)));
 711                         args.Add (new Argument (new TypeOfMethodInfo (delegate_method, loc)));
 712                         Expression e = new Invocation (ma, args).Resolve (ec);
 713                         if (e == null)
 714                                 return null;
 715
 716                         e = Convert.ExplicitConversion (ec, e, type, loc);
 717                         if (e == null)
 718                                 return null;
 719
 720                         return e.CreateExpressionTree (ec);
 721                 }
 722
 723                 public override Expression DoResolve (EmitContext ec)
 724                 {
 725                         constructor_method = Delegate.GetConstructor (ec.ContainerType, type);
 726
 727                         MethodInfo invoke_method = Delegate.GetInvokeMethod (ec.ContainerType, type);
 728                         method_group.DelegateType = type;
 729                         method_group.CustomErrorHandler = this;
 730
 731                         ArrayList arguments = CreateDelegateMethodArguments (invoke_method, loc);
 732                         method_group = method_group.OverloadResolve (ec, ref arguments, false, loc);
 733                         if (method_group == null)
 734                                 return null;
 735
 736                         delegate_method = (MethodInfo) method_group;
 737
 738                         if (TypeManager.IsNullableType (delegate_method.DeclaringType)) {
 739                                 Report.Error (1728, loc, "Cannot create delegate from method `{0}' because it is a member of System.Nullable<T> type",
 740                                         TypeManager.GetFullNameSignature (delegate_method));
 741                                 return null;
 742                         }
 743
 744                         Invocation.IsSpecialMethodInvocation (delegate_method, loc);
 745
 746                         ExtensionMethodGroupExpr emg = method_group as ExtensionMethodGroupExpr;
 747                         if (emg != null) {
 748                                 delegate_instance_expression = emg.ExtensionExpression;
 749                                 Type e_type = delegate_instance_expression.Type;
 750                                 if (TypeManager.IsValueType (e_type)) {
 751                                         Report.Error (1113, loc, "Extension method `{0}' of value type `{1}' cannot be used to create delegates",
 752                                                 TypeManager.CSharpSignature (delegate_method), TypeManager.CSharpName (e_type));
 753                                 }
 754                         }
 755
 756                         Type rt = TypeManager.TypeToCoreType (delegate_method.ReturnType);
 757                         Expression ret_expr = new TypeExpression (rt, loc);
 758                         if (!Delegate.IsTypeCovariant (ret_expr, (TypeManager.TypeToCoreType (invoke_method.ReturnType)))) {
 759                                 Error_ConversionFailed (ec, delegate_method, ret_expr);
 760                         }
 761
 762                         if (Invocation.IsMethodExcluded (delegate_method, loc)) {
 763                                 Report.SymbolRelatedToPreviousError (delegate_method);
 764                                 MethodOrOperator m = TypeManager.GetMethod (delegate_method) as MethodOrOperator;
 765                                 if (m != null && m.IsPartialDefinition) {
 766                                         Report.Error (762, loc, "Cannot create delegate from partial method declaration `{0}'",
 767                                                 TypeManager.CSharpSignature (delegate_method));
 768                                 } else {
 769                                         Report.Error (1618, loc, "Cannot create delegate with `{0}' because it has a Conditional attribute",
 770                                                 TypeManager.CSharpSignature (delegate_method));
 771                                 }
 772                         }
 773
 774                         DoResolveInstanceExpression (ec);
 775                         eclass = ExprClass.Value;
 776                         return this;
 777                 }
 778
 779                 void DoResolveInstanceExpression (EmitContext ec)
 780                 {
 781                         //
 782                         // Argument is another delegate
 783                         //
 784                         if (delegate_instance_expression != null)
 785                                 return;
 786
 787                         Expression instance = method_group.InstanceExpression;
 788                         if (instance != null && instance != EmptyExpression.Null) {
 789                                 delegate_instance_expression = instance;
 790                                 Type instance_type = delegate_instance_expression.Type;
 791                                 if (TypeManager.IsValueType (instance_type) || TypeManager.IsGenericParameter (instance_type)) {
 792                                         delegate_instance_expression = new BoxedCast (
 793                                                 delegate_instance_expression, TypeManager.object_type);
 794                                 }
 795                         } else if (!delegate_method.IsStatic && !ec.IsStatic) {
 796                                 delegate_instance_expression = ec.GetThis (loc);
 797                         }
 798                 }
 799
 800                 public override void Emit (EmitContext ec)
 801                 {
 802                         if (delegate_instance_expression == null)
 803                                 ec.ig.Emit (OpCodes.Ldnull);
 804                         else
 805                                 delegate_instance_expression.Emit (ec);
 806
 807                         if (!delegate_method.DeclaringType.IsSealed && delegate_method.IsVirtual && !method_group.IsBase) {
 808                                 ec.ig.Emit (OpCodes.Dup);
 809                                 ec.ig.Emit (OpCodes.Ldvirtftn, delegate_method);
 810                         } else {
 811                                 ec.ig.Emit (OpCodes.Ldftn, delegate_method);
 812                         }
 813
 814                         ec.ig.Emit (OpCodes.Newobj, constructor_method);
 815                 }
 816
 817                 void Error_ConversionFailed (EmitContext ec, MethodBase method, Expression return_type)
 818                 {
 819                         MethodInfo invoke_method = Delegate.GetInvokeMethod (ec.ContainerType, type);
 820                         string member_name = delegate_instance_expression != null ?
 821                                 Delegate.FullDelegateDesc (method) :
 822                                 TypeManager.GetFullNameSignature (method);
 823
 824                         Report.SymbolRelatedToPreviousError (type);
 825                         Report.SymbolRelatedToPreviousError (method);
 826                         if (RootContext.Version == LanguageVersion.ISO_1) {
 827                                 Report.Error (410, loc, "A method or delegate `{0} {1}' parameters and return type must be same as delegate `{2} {3}' parameters and return type",
 828                                         TypeManager.CSharpName (((MethodInfo) method).ReturnType), member_name,
 829                                         TypeManager.CSharpName (invoke_method.ReturnType), Delegate.FullDelegateDesc (invoke_method));
 830                                 return;
 831                         }
 832                         if (return_type == null) {
 833                                 Report.Error (123, loc, "A method or delegate `{0}' parameters do not match delegate `{1}' parameters",
 834                                         member_name, Delegate.FullDelegateDesc (invoke_method));
 835                                 return;
 836                         }
 837
 838                         Report.Error (407, loc, "A method or delegate `{0} {1}' return type does not match delegate `{2} {3}' return type",
 839                                 return_type.GetSignatureForError (), member_name,
 840                                 TypeManager.CSharpName (invoke_method.ReturnType), Delegate.FullDelegateDesc (invoke_method));
 841                 }
 842
 843                 public static MethodBase ImplicitStandardConversionExists (MethodGroupExpr mg, Type target_type)
 844                 {
 845                         if (target_type == TypeManager.delegate_type || target_type == TypeManager.multicast_delegate_type)
 846                                 return null;
 847
 848                         foreach (MethodInfo mi in mg.Methods){
 849                                 MethodBase mb = Delegate.VerifyMethod (mg.DeclaringType, target_type, mg, mi);
 850                                 if (mb != null)
 851                                         return mb;
 852                         }
 853                         return null;
 854                 }
 855
 856                 public override void MutateHoistedGenericType (AnonymousMethodStorey storey)
 857                 {
 858                         if (delegate_instance_expression != null)
 859                                 delegate_instance_expression.MutateHoistedGenericType (storey);
 860
 861                         delegate_method = storey.MutateGenericMethod (delegate_method);
 862                         constructor_method = storey.MutateConstructor (constructor_method);
 863                 }
 864
 865                 #region IErrorHandler Members
 866
 867                 public bool NoExactMatch (EmitContext ec, MethodBase method)
 868                 {
 869                         if (TypeManager.IsGenericMethod (method))
 870                                 return false;
 871
 872                         Error_ConversionFailed (ec, method, null);
 873                         return true;
 874                 }
 875
 876                 public bool AmbiguousCall (MethodBase ambiguous)
 877                 {
 878                         return false;
 879                 }
 880
 881                 #endregion
 882         }
 883
 884         //
 885         // Created from the conversion code
 886         //
 887         public class ImplicitDelegateCreation : DelegateCreation
 888         {
 889                 ImplicitDelegateCreation (Type t, MethodGroupExpr mg, Location l)
 890                 {
 891                         type = t;
 892                         this.method_group = mg;
 893                         loc = l;
 894                 }
 895
 896                 static public Expression Create (EmitContext ec, MethodGroupExpr mge,
 897                                                  Type target_type, Location loc)
 898                 {
 899                         ImplicitDelegateCreation d = new ImplicitDelegateCreation (target_type, mge, loc);
 900                         return d.DoResolve (ec);
 901                 }
 902         }
 903
 904         //
 905         // A delegate-creation-expression, invoked from the `New' class
 906         //
 907         public class NewDelegate : DelegateCreation
 908         {
 909                 public ArrayList Arguments;
 910
 911                 //
 912                 // This constructor is invoked from the `New' expression
 913                 //
 914                 public NewDelegate (Type type, ArrayList Arguments, Location loc)
 915                 {
 916                         this.type = type;
 917                         this.Arguments = Arguments;
 918                         this.loc  = loc;
 919                 }
 920
 921                 public override Expression DoResolve (EmitContext ec)
 922                 {
 923                         if (Arguments == null || Arguments.Count != 1) {
 924                                 Error_InvalidDelegateArgument ();
 925                                 return null;
 926                         }
 927
 928                         Argument a = (Argument) Arguments [0];
 929                         if (!a.ResolveMethodGroup (ec))
 930                                 return null;
 931
 932                         Expression e = a.Expr;
 933
 934                         AnonymousMethodExpression ame = e as AnonymousMethodExpression;
 935                         if (ame != null && RootContext.Version != LanguageVersion.ISO_1) {
 936                                 e = ame.Compatible (ec, type);
 937                                 if (e == null)
 938                                         return null;
 939
 940                                 return e.Resolve (ec);
 941                         }
 942
 943                         method_group = e as MethodGroupExpr;
 944                         if (method_group == null) {
 945                                 if (!TypeManager.IsDelegateType (e.Type)) {
 946                                         e.Error_UnexpectedKind (ResolveFlags.MethodGroup | ResolveFlags.Type, loc);
 947                                         return null;
 948                                 }
 949
 950                                 //
 951                                 // An argument is not a method but another delegate
 952                                 //
 953                                 delegate_instance_expression = e;
 954                                 method_group = new MethodGroupExpr (new MemberInfo [] {
 955                                         Delegate.GetInvokeMethod (ec.ContainerType, e.Type) }, e.Type, loc);
 956                         }
 957
 958                         return base.DoResolve (ec);
 959                 }
 960
 961                 void Error_InvalidDelegateArgument ()
 962                 {
 963                         Report.Error (149, loc, "Method name expected");
 964                 }
 965         }
 966
 967         public class DelegateInvocation : ExpressionStatement {
 968
 969                 readonly Expression InstanceExpr;
 970                 readonly ArrayList  Arguments;
 971
 972                 MethodInfo method;
 973
 974                 public DelegateInvocation (Expression instance_expr, ArrayList args, Location loc)
 975                 {
 976                         this.InstanceExpr = instance_expr;
 977                         this.Arguments = args;
 978                         this.loc = loc;
 979                 }
 980
 981                 public override Expression CreateExpressionTree (EmitContext ec)
 982                 {
 983                         ArrayList args;
 984                         if (Arguments == null)
 985                                 args = new ArrayList (1);
 986                         else
 987                                 args = new ArrayList (Arguments.Count + 1);
 988
 989                         args.Add (new Argument (InstanceExpr.CreateExpressionTree (ec)));
 990                         if (Arguments != null) {
 991                                 foreach (Argument a in Arguments)
 992                                         args.Add (new Argument (a.Expr.CreateExpressionTree (ec)));
 993                         }
 994
 995                         return CreateExpressionFactoryCall ("Invoke", args);
 996                 }
 997
 998                 public override Expression DoResolve (EmitContext ec)
 999                 {
1000                         if (InstanceExpr is EventExpr) {
1001                                 ((EventExpr) InstanceExpr).Error_CannotAssign ();
1002                                 return null;
1003                         }
1004
1005                         Type del_type = InstanceExpr.Type;
1006                         if (del_type == null)
1007                                 return null;
1008
1009                         if (Arguments != null){
1010                                 foreach (Argument a in Arguments){
1011                                         if (!a.Resolve (ec, loc))
1012                                                 return null;
1013                                 }
1014                         }
1015
1016                         if (!Delegate.VerifyApplicability (ec, del_type, Arguments, loc))
1017                                 return null;
1018
1019                         method = Delegate.GetInvokeMethod (ec.ContainerType, del_type);
1020                         type = TypeManager.TypeToCoreType (method.ReturnType);
1021                         eclass = ExprClass.Value;
1022
1023                         return this;
1024                 }
1025
1026                 public override void Emit (EmitContext ec)
1027                 {
1028                         //
1029                         // Invocation on delegates call the virtual Invoke member
1030                         // so we are always `instance' calls
1031                         //
1032                         Invocation.EmitCall (ec, false, InstanceExpr, method, Arguments, loc);
1033                 }
1034
1035                 public override void EmitStatement (EmitContext ec)
1036                 {
1037                         Emit (ec);
1038                         //
1039                         // Pop the return value if there is one
1040                         //
1041                         if (type != TypeManager.void_type)
1042                                 ec.ig.Emit (OpCodes.Pop);
1043                 }
1044
1045                 public override void MutateHoistedGenericType (AnonymousMethodStorey storey)
1046                 {
1047                         method = storey.MutateGenericMethod (method);
1048                         type = storey.MutateType (type);
1049
1050                         if (Arguments != null) {
1051                                 foreach (Argument a in Arguments) {
1052                                         a.Expr.MutateHoistedGenericType (storey);
1053                                 }
1054                         }
1055
1056                         InstanceExpr.MutateHoistedGenericType (storey);
1057                 }
1058         }
1059 }