mcs/decl.cs

   1 //
   2 // decl.cs: Declaration base class for structs, classes, enums and interfaces.
   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 Ximian, Inc (http://www.ximian.com)
  10 // Copyright 2004-2008 Novell, Inc
  11 //
  12 //
  13
  14 using System;
  15 using System.Text;
  16 using System.Collections.Generic;
  17 using System.Globalization;
  18 using System.Reflection.Emit;
  19 using System.Reflection;
  20
  21 #if NET_2_1
  22 using XmlElement = System.Object;
  23 #else
  24 using System.Xml;
  25 #endif
  26
  27 namespace Mono.CSharp {
  28
  29         //
  30         // Better name would be DottenName
  31         //
  32         public class MemberName {
  33                 public readonly string Name;
  34                 public TypeArguments TypeArguments;
  35
  36                 public readonly MemberName Left;
  37                 public readonly Location Location;
  38
  39                 public static readonly MemberName Null = new MemberName ("");
  40
  41                 bool is_double_colon;
  42
  43                 private MemberName (MemberName left, string name, bool is_double_colon,
  44                                     Location loc)
  45                 {
  46                         this.Name = name;
  47                         this.Location = loc;
  48                         this.is_double_colon = is_double_colon;
  49                         this.Left = left;
  50                 }
  51
  52                 private MemberName (MemberName left, string name, bool is_double_colon,
  53                                     TypeArguments args, Location loc)
  54                         : this (left, name, is_double_colon, loc)
  55                 {
  56                         if (args != null && args.Count > 0)
  57                                 this.TypeArguments = args;
  58                 }
  59
  60                 public MemberName (string name)
  61                         : this (name, Location.Null)
  62                 { }
  63
  64                 public MemberName (string name, Location loc)
  65                         : this (null, name, false, loc)
  66                 { }
  67
  68                 public MemberName (string name, TypeArguments args, Location loc)
  69                         : this (null, name, false, args, loc)
  70                 { }
  71
  72                 public MemberName (MemberName left, string name)
  73                         : this (left, name, left != null ? left.Location : Location.Null)
  74                 { }
  75
  76                 public MemberName (MemberName left, string name, Location loc)
  77                         : this (left, name, false, loc)
  78                 { }
  79
  80                 public MemberName (MemberName left, string name, TypeArguments args, Location loc)
  81                         : this (left, name, false, args, loc)
  82                 { }
  83
  84                 public MemberName (string alias, string name, TypeArguments args, Location loc)
  85                         : this (new MemberName (alias, loc), name, true, args, loc)
  86                 { }
  87
  88                 public MemberName (MemberName left, MemberName right)
  89                         : this (left, right, right.Location)
  90                 { }
  91
  92                 public MemberName (MemberName left, MemberName right, Location loc)
  93                         : this (null, right.Name, false, right.TypeArguments, loc)
  94                 {
  95                         if (right.is_double_colon)
  96                                 throw new InternalErrorException ("Cannot append double_colon member name");
  97                         this.Left = (right.Left == null) ? left : new MemberName (left, right.Left);
  98                 }
  99
 100                 // TODO: Remove
 101                 public string GetName ()
 102                 {
 103                         return GetName (false);
 104                 }
 105
 106                 public int Arity {
 107                         get {
 108                                 return TypeArguments == null ? 0 : TypeArguments.Count;
 109                         }
 110                 }
 111
 112                 public bool IsGeneric {
 113                         get {
 114                                 if (TypeArguments != null)
 115                                         return true;
 116                                 else if (Left != null)
 117                                         return Left.IsGeneric;
 118                                 else
 119                                         return false;
 120                         }
 121                 }
 122
 123                 public string GetName (bool is_generic)
 124                 {
 125                         string name = is_generic ? Basename : Name;
 126                         if (Left != null)
 127                                 return Left.GetName (is_generic) + (is_double_colon ? "::" : ".") + name;
 128
 129                         return name;
 130                 }
 131
 132                 public ATypeNameExpression GetTypeExpression ()
 133                 {
 134                         if (Left == null) {
 135                                 if (TypeArguments != null)
 136                                         return new SimpleName (Name, TypeArguments, Location);
 137
 138                                 return new SimpleName (Name, Location);
 139                         }
 140
 141                         if (is_double_colon) {
 142                                 if (Left.Left != null)
 143                                         throw new InternalErrorException ("The left side of a :: should be an identifier");
 144                                 return new QualifiedAliasMember (Left.Name, Name, TypeArguments, Location);
 145                         }
 146
 147                         Expression lexpr = Left.GetTypeExpression ();
 148                         return new MemberAccess (lexpr, Name, TypeArguments, Location);
 149                 }
 150
 151                 public MemberName Clone ()
 152                 {
 153                         MemberName left_clone = Left == null ? null : Left.Clone ();
 154                         return new MemberName (left_clone, Name, is_double_colon, TypeArguments, Location);
 155                 }
 156
 157                 public string Basename {
 158                         get {
 159                                 if (TypeArguments != null)
 160                                         return MakeName (Name, TypeArguments);
 161                                 return Name;
 162                         }
 163                 }
 164
 165                 public string GetSignatureForError ()
 166                 {
 167                         string append = TypeArguments == null ? "" : "<" + TypeArguments.GetSignatureForError () + ">";
 168                         if (Left == null)
 169                                 return Name + append;
 170                         string connect = is_double_colon ? "::" : ".";
 171                         return Left.GetSignatureForError () + connect + Name + append;
 172                 }
 173
 174                 public override bool Equals (object other)
 175                 {
 176                         return Equals (other as MemberName);
 177                 }
 178
 179                 public bool Equals (MemberName other)
 180                 {
 181                         if (this == other)
 182                                 return true;
 183                         if (other == null || Name != other.Name)
 184                                 return false;
 185                         if (is_double_colon != other.is_double_colon)
 186                                 return false;
 187
 188                         if ((TypeArguments != null) &&
 189                             (other.TypeArguments == null || TypeArguments.Count != other.TypeArguments.Count))
 190                                 return false;
 191
 192                         if ((TypeArguments == null) && (other.TypeArguments != null))
 193                                 return false;
 194
 195                         if (Left == null)
 196                                 return other.Left == null;
 197
 198                         return Left.Equals (other.Left);
 199                 }
 200
 201                 public override int GetHashCode ()
 202                 {
 203                         int hash = Name.GetHashCode ();
 204                         for (MemberName n = Left; n != null; n = n.Left)
 205                                 hash ^= n.Name.GetHashCode ();
 206                         if (is_double_colon)
 207                                 hash ^= 0xbadc01d;
 208
 209                         if (TypeArguments != null)
 210                                 hash ^= TypeArguments.Count << 5;
 211
 212                         return hash & 0x7FFFFFFF;
 213                 }
 214
 215                 public int CountTypeArguments {
 216                         get {
 217                                 if (TypeArguments != null)
 218                                         return TypeArguments.Count;
 219                                 else if (Left != null)
 220                                         return Left.CountTypeArguments;
 221                                 else
 222                                         return 0;
 223                         }
 224                 }
 225
 226                 public static string MakeName (string name, TypeArguments args)
 227                 {
 228                         if (args == null)
 229                                 return name;
 230
 231                         return name + "`" + args.Count;
 232                 }
 233
 234                 public static string MakeName (string name, int count)
 235                 {
 236                         return name + "`" + count;
 237                 }
 238         }
 239
 240         public class SimpleMemberName
 241         {
 242                 public string Value;
 243                 public Location Location;
 244
 245                 public SimpleMemberName (string name, Location loc)
 246                 {
 247                         this.Value = name;
 248                         this.Location = loc;
 249                 }
 250         }
 251
 252         /// <summary>
 253         ///   Base representation for members.  This is used to keep track
 254         ///   of Name, Location and Modifier flags, and handling Attributes.
 255         /// </summary>
 256         [System.Diagnostics.DebuggerDisplay ("{GetSignatureForError()}")]
 257         public abstract class MemberCore : Attributable, IMemberContext, IMemberDefinition
 258         {
 259                 /// <summary>
 260                 ///   Public name
 261                 /// </summary>
 262
 263                 protected string cached_name;
 264                 // TODO: Remove in favor of MemberName
 265                 public string Name {
 266                         get {
 267                                 if (cached_name == null)
 268                                         cached_name = MemberName.GetName (!(this is GenericMethod) && !(this is Method));
 269                                 return cached_name;
 270                         }
 271                 }
 272
 273                 string IMemberDefinition.Name {
 274                         get {
 275                                 return member_name.Name;
 276                         }
 277                 }
 278
 279                 // Is not readonly because of IndexerName attribute
 280                 private MemberName member_name;
 281                 public MemberName MemberName {
 282                         get { return member_name; }
 283                 }
 284
 285                 /// <summary>
 286                 ///   Modifier flags that the user specified in the source code
 287                 /// </summary>
 288                 private Modifiers mod_flags;
 289                 public Modifiers ModFlags {
 290                         set {
 291                                 mod_flags = value;
 292                                 if ((value & Modifiers.COMPILER_GENERATED) != 0)
 293                                         caching_flags = Flags.IsUsed | Flags.IsAssigned;
 294                         }
 295                         get {
 296                                 return mod_flags;
 297                         }
 298                 }
 299
 300                 public /*readonly*/ TypeContainer Parent;
 301
 302                 /// <summary>
 303                 ///   Location where this declaration happens
 304                 /// </summary>
 305                 public Location Location {
 306                         get { return member_name.Location; }
 307                 }
 308
 309                 /// <summary>
 310                 ///   XML documentation comment
 311                 /// </summary>
 312                 protected string comment;
 313
 314                 /// <summary>
 315                 ///   Represents header string for documentation comment
 316                 ///   for each member types.
 317                 /// </summary>
 318                 public abstract string DocCommentHeader { get; }
 319
 320                 [Flags]
 321                 public enum Flags {
 322                         Obsolete_Undetected = 1,                // Obsolete attribute has not been detected yet
 323                         Obsolete = 1 << 1,                      // Type has obsolete attribute
 324                         ClsCompliance_Undetected = 1 << 2,      // CLS Compliance has not been detected yet
 325                         ClsCompliant = 1 << 3,                  // Type is CLS Compliant
 326                         CloseTypeCreated = 1 << 4,              // Tracks whether we have Closed the type
 327                         HasCompliantAttribute_Undetected = 1 << 5,      // Presence of CLSCompliantAttribute has not been detected
 328                         HasClsCompliantAttribute = 1 << 6,                      // Type has CLSCompliantAttribute
 329                         ClsCompliantAttributeFalse = 1 << 7,                    // Member has CLSCompliant(false)
 330                         Excluded_Undetected = 1 << 8,           // Conditional attribute has not been detected yet
 331                         Excluded = 1 << 9,                                      // Method is conditional
 332                         MethodOverloadsExist = 1 << 10,         // Test for duplication must be performed
 333                         IsUsed = 1 << 11,
 334                         IsAssigned = 1 << 12,                           // Field is assigned
 335                         HasExplicitLayout       = 1 << 13,
 336                         PartialDefinitionExists = 1 << 14,      // Set when corresponding partial method definition exists
 337                         HasStructLayout         = 1 << 15                       // Has StructLayoutAttribute
 338                 }
 339
 340                 /// <summary>
 341                 ///   MemberCore flags at first detected then cached
 342                 /// </summary>
 343                 internal Flags caching_flags;
 344
 345                 public MemberCore (DeclSpace parent, MemberName name, Attributes attrs)
 346                 {
 347                         this.Parent = parent as TypeContainer;
 348                         member_name = name;
 349                         caching_flags = Flags.Obsolete_Undetected | Flags.ClsCompliance_Undetected | Flags.HasCompliantAttribute_Undetected | Flags.Excluded_Undetected;
 350                         AddAttributes (attrs, this);
 351                 }
 352
 353                 public virtual Assembly Assembly {
 354                         get { return Parent.Module.Assembly; }
 355                 }
 356
 357                 protected virtual void SetMemberName (MemberName new_name)
 358                 {
 359                         member_name = new_name;
 360                         cached_name = null;
 361                 }
 362
 363                 protected bool CheckAbstractAndExtern (bool has_block)
 364                 {
 365                         if (Parent.PartialContainer.Kind == MemberKind.Interface)
 366                                 return true;
 367
 368                         if (has_block) {
 369                                 if ((ModFlags & Modifiers.EXTERN) != 0) {
 370                                         Report.Error (179, Location, "`{0}' cannot declare a body because it is marked extern",
 371                                                 GetSignatureForError ());
 372                                         return false;
 373                                 }
 374
 375                                 if ((ModFlags & Modifiers.ABSTRACT) != 0) {
 376                                         Report.Error (500, Location, "`{0}' cannot declare a body because it is marked abstract",
 377                                                 GetSignatureForError ());
 378                                         return false;
 379                                 }
 380                         } else {
 381                                 if ((ModFlags & (Modifiers.ABSTRACT | Modifiers.EXTERN | Modifiers.PARTIAL)) == 0 && !(Parent is Delegate)) {
 382                                         if (RootContext.Version >= LanguageVersion.V_3) {
 383                                                 Property.PropertyMethod pm = this as Property.PropertyMethod;
 384                                                 if (pm is Indexer.GetIndexerMethod || pm is Indexer.SetIndexerMethod)
 385                                                         pm = null;
 386
 387                                                 if (pm != null && (pm.Property.Get.IsDummy || pm.Property.Set.IsDummy)) {
 388                                                         Report.Error (840, Location,
 389                                                                 "`{0}' must have a body because it is not marked abstract or extern. The property can be automatically implemented when you define both accessors",
 390                                                                 GetSignatureForError ());
 391                                                         return false;
 392                                                 }
 393                                         }
 394
 395                                         Report.Error (501, Location, "`{0}' must have a body because it is not marked abstract, extern, or partial",
 396                                                       GetSignatureForError ());
 397                                         return false;
 398                                 }
 399                         }
 400
 401                         return true;
 402                 }
 403
 404                 protected void CheckProtectedModifier ()
 405                 {
 406                         if ((ModFlags & Modifiers.PROTECTED) == 0)
 407                                 return;
 408
 409                         if (Parent.PartialContainer.Kind == MemberKind.Struct) {
 410                                 Report.Error (666, Location, "`{0}': Structs cannot contain protected members",
 411                                         GetSignatureForError ());
 412                                 return;
 413                         }
 414
 415                         if ((Parent.ModFlags & Modifiers.STATIC) != 0) {
 416                                 Report.Error (1057, Location, "`{0}': Static classes cannot contain protected members",
 417                                         GetSignatureForError ());
 418                                 return;
 419                         }
 420
 421                         if ((Parent.ModFlags & Modifiers.SEALED) != 0 && (ModFlags & Modifiers.OVERRIDE) == 0 &&
 422                                 !(this is Destructor)) {
 423                                 Report.Warning (628, 4, Location, "`{0}': new protected member declared in sealed class",
 424                                         GetSignatureForError ());
 425                                 return;
 426                         }
 427                 }
 428
 429                 public abstract bool Define ();
 430
 431                 public virtual string DocComment {
 432                         get {
 433                                 return comment;
 434                         }
 435                         set {
 436                                 comment = value;
 437                         }
 438                 }
 439
 440                 //
 441                 // Returns full member name for error message
 442                 //
 443                 public virtual string GetSignatureForError ()
 444                 {
 445                         if (Parent == null || Parent.Parent == null)
 446                                 return member_name.GetSignatureForError ();
 447
 448                         return Parent.GetSignatureForError () + "." + member_name.GetSignatureForError ();
 449                 }
 450
 451                 /// <summary>
 452                 /// Base Emit method. This is also entry point for CLS-Compliant verification.
 453                 /// </summary>
 454                 public virtual void Emit ()
 455                 {
 456                         if (!RootContext.VerifyClsCompliance)
 457                                 return;
 458
 459                         VerifyClsCompliance ();
 460                 }
 461
 462                 public bool IsCompilerGenerated {
 463                         get     {
 464                                 if ((mod_flags & Modifiers.COMPILER_GENERATED) != 0)
 465                                         return true;
 466
 467                                 return Parent == null ? false : Parent.IsCompilerGenerated;
 468                         }
 469                 }
 470
 471                 public bool IsImported {
 472                         get {
 473                                 return false;
 474                         }
 475                 }
 476
 477                 public virtual bool IsUsed {
 478                         get { return (caching_flags & Flags.IsUsed) != 0; }
 479                 }
 480
 481                 protected Report Report {
 482                         get {
 483                                 return Compiler.Report;
 484                         }
 485                 }
 486
 487                 public void SetIsUsed ()
 488                 {
 489                         caching_flags |= Flags.IsUsed;
 490                 }
 491
 492                 public void SetIsAssigned ()
 493                 {
 494                         caching_flags |= Flags.IsAssigned;
 495                 }
 496
 497                 /// <summary>
 498                 /// Returns instance of ObsoleteAttribute for this MemberCore
 499                 /// </summary>
 500                 public virtual ObsoleteAttribute GetAttributeObsolete ()
 501                 {
 502                         if ((caching_flags & (Flags.Obsolete_Undetected | Flags.Obsolete)) == 0)
 503                                 return null;
 504
 505                         caching_flags &= ~Flags.Obsolete_Undetected;
 506
 507                         if (OptAttributes == null)
 508                                 return null;
 509
 510                         Attribute obsolete_attr = OptAttributes.Search (PredefinedAttributes.Get.Obsolete);
 511                         if (obsolete_attr == null)
 512                                 return null;
 513
 514                         caching_flags |= Flags.Obsolete;
 515
 516                         ObsoleteAttribute obsolete = obsolete_attr.GetObsoleteAttribute ();
 517                         if (obsolete == null)
 518                                 return null;
 519
 520                         return obsolete;
 521                 }
 522
 523                 /// <summary>
 524                 /// Checks for ObsoleteAttribute presence. It's used for testing of all non-types elements
 525                 /// </summary>
 526                 public virtual void CheckObsoleteness (Location loc)
 527                 {
 528                         ObsoleteAttribute oa = GetAttributeObsolete ();
 529                         if (oa != null)
 530                                 AttributeTester.Report_ObsoleteMessage (oa, GetSignatureForError (), loc, Report);
 531                 }
 532
 533                 //
 534                 // Checks whether the type P is as accessible as this member
 535                 //
 536                 public bool IsAccessibleAs (TypeSpec p)
 537                 {
 538                         //
 539                         // if M is private, its accessibility is the same as this declspace.
 540                         // we already know that P is accessible to T before this method, so we
 541                         // may return true.
 542                         //
 543                         if ((mod_flags & Modifiers.PRIVATE) != 0)
 544                                 return true;
 545
 546                         while (TypeManager.HasElementType (p))
 547                                 p = TypeManager.GetElementType (p);
 548
 549                         if (p.IsGenericParameter)
 550                                 return true;
 551
 552                         for (TypeSpec p_parent; p != null; p = p_parent) {
 553                                 p_parent = p.DeclaringType;
 554
 555                                 if (p.IsGeneric) {
 556                                         foreach (TypeSpec t in p.TypeArguments) {
 557                                                 if (!IsAccessibleAs (t))
 558                                                         return false;
 559                                         }
 560                                 }
 561
 562                                 var pAccess = p.Modifiers & Modifiers.AccessibilityMask;
 563                                 if (pAccess == Modifiers.PUBLIC)
 564                                         continue;
 565
 566                                 bool same_access_restrictions = false;
 567                                 for (MemberCore mc = this; !same_access_restrictions && mc != null && mc.Parent != null; mc = mc.Parent) {
 568                                         var al = mc.ModFlags & Modifiers.AccessibilityMask;
 569                                         switch (pAccess) {
 570                                         case Modifiers.INTERNAL:
 571                                                 if (al == Modifiers.PRIVATE || al == Modifiers.INTERNAL)
 572                                                         same_access_restrictions = TypeManager.IsThisOrFriendAssembly (Parent.Module.Assembly, p.Assembly);
 573
 574                                                 break;
 575
 576                                         case Modifiers.PROTECTED:
 577                                                 if (al == Modifiers.PROTECTED) {
 578                                                         same_access_restrictions = mc.Parent.IsBaseTypeDefinition (p_parent);
 579                                                         break;
 580                                                 }
 581
 582                                                 if (al == Modifiers.PRIVATE) {
 583                                                         //
 584                                                         // When type is private and any of its parents derives from
 585                                                         // protected type then the type is accessible
 586                                                         //
 587                                                         while (mc.Parent != null) {
 588                                                                 if (mc.Parent.IsBaseTypeDefinition (p_parent))
 589                                                                         same_access_restrictions = true;
 590                                                                 mc = mc.Parent;
 591                                                         }
 592                                                 }
 593
 594                                                 break;
 595
 596                                         case Modifiers.PROTECTED | Modifiers.INTERNAL:
 597                                                 if (al == Modifiers.INTERNAL)
 598                                                         same_access_restrictions = TypeManager.IsThisOrFriendAssembly (Parent.Module.Assembly, p.Assembly);
 599                                                 else if (al == Modifiers.PROTECTED)
 600                                                         same_access_restrictions = mc.Parent.IsBaseTypeDefinition (p_parent);
 601                                                 else if (al == (Modifiers.PROTECTED | Modifiers.INTERNAL))
 602                                                         same_access_restrictions = mc.Parent.IsBaseTypeDefinition (p_parent) &&
 603                                                                 TypeManager.IsThisOrFriendAssembly (Parent.Module.Assembly, p.Assembly);
 604                                                 break;
 605
 606                                         case Modifiers.PRIVATE:
 607                                                 //
 608                                                 // Both are private and share same parent
 609                                                 //
 610                                                 if (al == Modifiers.PRIVATE) {
 611                                                         var decl = mc.Parent;
 612                                                         do {
 613                                                                 same_access_restrictions = decl.CurrentType == p_parent;
 614                                                         } while (!same_access_restrictions && !decl.IsTopLevel && (decl = decl.Parent) != null);
 615                                                 }
 616
 617                                                 break;
 618
 619                                         default:
 620                                                 throw new InternalErrorException (al.ToString ());
 621                                         }
 622                                 }
 623
 624                                 if (!same_access_restrictions)
 625                                         return false;
 626                         }
 627
 628                         return true;
 629                 }
 630
 631                 /// <summary>
 632                 /// Analyze whether CLS-Compliant verification must be execute for this MemberCore.
 633                 /// </summary>
 634                 public override bool IsClsComplianceRequired ()
 635                 {
 636                         if ((caching_flags & Flags.ClsCompliance_Undetected) == 0)
 637                                 return (caching_flags & Flags.ClsCompliant) != 0;
 638
 639                         caching_flags &= ~Flags.ClsCompliance_Undetected;
 640
 641                         if (HasClsCompliantAttribute) {
 642                                 if ((caching_flags & Flags.ClsCompliantAttributeFalse) != 0)
 643                                         return false;
 644
 645                                 caching_flags |= Flags.ClsCompliant;
 646                                 return true;
 647                         }
 648
 649                         if (Parent.PartialContainer.IsClsComplianceRequired ()) {
 650                                 caching_flags |= Flags.ClsCompliant;
 651                                 return true;
 652                         }
 653
 654                         return false;
 655                 }
 656
 657                 public virtual string[] ConditionalConditions ()
 658                 {
 659                         return null;
 660                 }
 661
 662                 /// <summary>
 663                 /// Returns true when MemberCore is exposed from assembly.
 664                 /// </summary>
 665                 public bool IsExposedFromAssembly ()
 666                 {
 667                         if ((ModFlags & (Modifiers.PUBLIC | Modifiers.PROTECTED)) == 0)
 668                                 return false;
 669
 670                         DeclSpace parentContainer = Parent.PartialContainer;
 671                         while (parentContainer != null && parentContainer.ModFlags != 0) {
 672                                 if ((parentContainer.ModFlags & (Modifiers.PUBLIC | Modifiers.PROTECTED)) == 0)
 673                                         return false;
 674                                 parentContainer = parentContainer.Parent;
 675                         }
 676                         return true;
 677                 }
 678
 679                 public virtual ExtensionMethodGroupExpr LookupExtensionMethod (TypeSpec extensionType, string name, int arity, Location loc)
 680                 {
 681                         return Parent.LookupExtensionMethod (extensionType, name, arity, loc);
 682                 }
 683
 684                 public virtual FullNamedExpression LookupNamespaceAlias (string name)
 685                 {
 686                         return Parent.NamespaceEntry.LookupNamespaceAlias (name);
 687                 }
 688
 689                 public virtual FullNamedExpression LookupNamespaceOrType (string name, int arity, Location loc, bool ignore_cs0104)
 690                 {
 691                         return Parent.LookupNamespaceOrType (name, arity, loc, ignore_cs0104);
 692                 }
 693
 694                 /// <summary>
 695                 /// Goes through class hierarchy and gets value of first found CLSCompliantAttribute.
 696                 /// If no is attribute exists then assembly CLSCompliantAttribute is returned.
 697                 /// </summary>
 698                 public bool IsNotCLSCompliant ()
 699                 {
 700                         if ((caching_flags & Flags.HasCompliantAttribute_Undetected) == 0)
 701                                 return (caching_flags & Flags.ClsCompliantAttributeFalse) != 0;
 702
 703                         caching_flags &= ~Flags.HasCompliantAttribute_Undetected;
 704
 705                         if (OptAttributes != null) {
 706                                 Attribute cls_attribute = OptAttributes.Search (PredefinedAttributes.Get.CLSCompliant);
 707                                 if (cls_attribute != null) {
 708                                         caching_flags |= Flags.HasClsCompliantAttribute;
 709                                         if (cls_attribute.GetClsCompliantAttributeValue ())
 710                                                 return false;
 711
 712                                         caching_flags |= Flags.ClsCompliantAttributeFalse;
 713                                         return true;
 714                                 }
 715                         }
 716
 717                         return false;
 718                 }
 719
 720                 /// <summary>
 721                 /// Returns true if MemberCore is explicitly marked with CLSCompliantAttribute
 722                 /// </summary>
 723                 protected bool HasClsCompliantAttribute {
 724                         get {
 725                                 if ((caching_flags & Flags.HasCompliantAttribute_Undetected) != 0)
 726                                         IsNotCLSCompliant ();
 727
 728                                 return (caching_flags & Flags.HasClsCompliantAttribute) != 0;
 729                         }
 730                 }
 731
 732                 /// <summary>
 733                 /// Returns true when a member supports multiple overloads (methods, indexers, etc)
 734                 /// </summary>
 735                 public virtual bool EnableOverloadChecks (MemberCore overload)
 736                 {
 737                         return false;
 738                 }
 739
 740                 /// <summary>
 741                 /// The main virtual method for CLS-Compliant verifications.
 742                 /// The method returns true if member is CLS-Compliant and false if member is not
 743                 /// CLS-Compliant which means that CLS-Compliant tests are not necessary. A descendants override it
 744                 /// and add their extra verifications.
 745                 /// </summary>
 746                 protected virtual bool VerifyClsCompliance ()
 747                 {
 748                         if (HasClsCompliantAttribute) {
 749                                 if (CodeGen.Assembly.ClsCompliantAttribute == null) {
 750                                         Attribute a = OptAttributes.Search (PredefinedAttributes.Get.CLSCompliant);
 751                                         if ((caching_flags & Flags.ClsCompliantAttributeFalse) != 0) {
 752                                                 Report.Warning (3021, 2, a.Location,
 753                                                         "`{0}' does not need a CLSCompliant attribute because the assembly is not marked as CLS-compliant",
 754                                                         GetSignatureForError ());
 755                                         } else {
 756                                                 Report.Warning (3014, 1, a.Location,
 757                                                         "`{0}' cannot be marked as CLS-compliant because the assembly is not marked as CLS-compliant",
 758                                                         GetSignatureForError ());
 759                                         }
 760                                         return false;
 761                                 }
 762
 763                                 if (!IsExposedFromAssembly ()) {
 764                                         Attribute a = OptAttributes.Search (PredefinedAttributes.Get.CLSCompliant);
 765                                         Report.Warning (3019, 2, a.Location, "CLS compliance checking will not be performed on `{0}' because it is not visible from outside this assembly", GetSignatureForError ());
 766                                         return false;
 767                                 }
 768
 769                                 if ((caching_flags & Flags.ClsCompliantAttributeFalse) != 0) {
 770                                         if (Parent.Kind == MemberKind.Interface && Parent.IsClsComplianceRequired ()) {
 771                                                 Report.Warning (3010, 1, Location, "`{0}': CLS-compliant interfaces must have only CLS-compliant members", GetSignatureForError ());
 772                                         } else if (Parent.Kind == MemberKind.Class && (ModFlags & Modifiers.ABSTRACT) != 0 && Parent.IsClsComplianceRequired ()) {
 773                                                 Report.Warning (3011, 1, Location, "`{0}': only CLS-compliant members can be abstract", GetSignatureForError ());
 774                                         }
 775
 776                                         return false;
 777                                 }
 778
 779                                 if (Parent.Parent != null && !Parent.IsClsComplianceRequired ()) {
 780                                         Attribute a = OptAttributes.Search (PredefinedAttributes.Get.CLSCompliant);
 781                                         Report.Warning (3018, 1, a.Location, "`{0}' cannot be marked as CLS-compliant because it is a member of non CLS-compliant type `{1}'",
 782                                                 GetSignatureForError (), Parent.GetSignatureForError ());
 783                                         return false;
 784                                 }
 785                         } else {
 786                                 if (!IsExposedFromAssembly ())
 787                                         return false;
 788
 789                                 if (!Parent.PartialContainer.IsClsComplianceRequired ())
 790                                         return false;
 791                         }
 792
 793                         if (member_name.Name [0] == '_') {
 794                                 Report.Warning (3008, 1, Location, "Identifier `{0}' is not CLS-compliant", GetSignatureForError () );
 795                         }
 796
 797                         return true;
 798                 }
 799
 800                 //
 801                 // Raised (and passed an XmlElement that contains the comment)
 802                 // when GenerateDocComment is writing documentation expectedly.
 803                 //
 804                 internal virtual void OnGenerateDocComment (XmlElement intermediateNode)
 805                 {
 806                 }
 807
 808                 //
 809                 // Returns a string that represents the signature for this
 810                 // member which should be used in XML documentation.
 811                 //
 812                 public virtual string GetDocCommentName (DeclSpace ds)
 813                 {
 814                         if (ds == null || this is DeclSpace)
 815                                 return DocCommentHeader + Name;
 816                         else
 817                                 return String.Concat (DocCommentHeader, ds.Name, ".", Name);
 818                 }
 819
 820                 //
 821                 // Generates xml doc comments (if any), and if required,
 822                 // handle warning report.
 823                 //
 824                 internal virtual void GenerateDocComment (DeclSpace ds)
 825                 {
 826                         try {
 827                                 DocUtil.GenerateDocComment (this, ds, Report);
 828                         } catch (Exception e) {
 829                                 throw new InternalErrorException (this, e);
 830                         }
 831                 }
 832
 833                 #region IMemberContext Members
 834
 835                 public virtual CompilerContext Compiler {
 836                         get { return Parent.Compiler; }
 837                 }
 838
 839                 public virtual TypeSpec CurrentType {
 840                         get { return Parent.CurrentType; }
 841                 }
 842
 843                 public MemberCore CurrentMemberDefinition {
 844                         get { return this; }
 845                 }
 846
 847                 public virtual TypeParameter[] CurrentTypeParameters {
 848                         get { return null; }
 849                 }
 850
 851                 public virtual bool HasUnresolvedConstraints {
 852                         get { return false; }
 853                 }
 854
 855                 public bool IsObsolete {
 856                         get {
 857                                 if (GetAttributeObsolete () != null)
 858                                         return true;
 859
 860                                 return Parent == null ? false : Parent.IsObsolete;
 861                         }
 862                 }
 863
 864                 public bool IsUnsafe {
 865                         get {
 866                                 if ((ModFlags & Modifiers.UNSAFE) != 0)
 867                                         return true;
 868
 869                                 return Parent == null ? false : Parent.IsUnsafe;
 870                         }
 871                 }
 872
 873                 public bool IsStatic {
 874                         get {
 875                                 return (ModFlags & Modifiers.STATIC) != 0;
 876                         }
 877                 }
 878
 879                 #endregion
 880         }
 881
 882         //
 883         // Base member specification. A member specification contains
 884         // member details which can alter in the context (e.g. generic instances)
 885         //
 886         public abstract class MemberSpec
 887         {
 888                 [Flags]
 889                 protected enum StateFlags
 890                 {
 891                         Obsolete_Undetected = 1,        // Obsolete attribute has not been detected yet
 892                         Obsolete = 1 << 1,                      // Member has obsolete attribute
 893                         CLSCompliant_Undetected = 1 << 3,       // CLSCompliant attribute has not been detected yet
 894                         CLSCompliant = 1 << 4,          // Member is CLS Compliant
 895
 896                         IsAccessor = 1 << 9,            // Method is an accessor
 897                         IsGeneric = 1 << 10,            // Member contains type arguments
 898
 899                         PendingMetaInflate = 1 << 12,
 900                         PendingMakeMethod = 1 << 13,
 901                         PendingMemberCacheMembers = 1 << 14,
 902                         PendingBaseTypeInflate = 1 << 15,
 903                         InterfacesExpanded = 1 << 16,
 904                         IsNotRealProperty = 1 << 17,
 905                 }
 906
 907                 protected Modifiers modifiers;
 908                 protected StateFlags state;
 909                 protected IMemberDefinition definition;
 910                 public readonly MemberKind Kind;
 911                 protected TypeSpec declaringType;
 912
 913 #if DEBUG
 914                 static int counter;
 915                 public int ID = counter++;
 916 #endif
 917
 918                 protected MemberSpec (MemberKind kind, TypeSpec declaringType, IMemberDefinition definition, Modifiers modifiers)
 919                 {
 920                         this.Kind = kind;
 921                         this.declaringType = declaringType;
 922                         this.definition = definition;
 923                         this.modifiers = modifiers;
 924
 925                         state = StateFlags.Obsolete_Undetected | StateFlags.CLSCompliant_Undetected;
 926                 }
 927
 928                 #region Properties
 929
 930                 public Assembly Assembly {
 931                         get {
 932                                 return definition.Assembly;
 933                         }
 934                 }
 935
 936                 public virtual int Arity {
 937                         get {
 938                                 return 0;
 939                         }
 940                 }
 941
 942                 public TypeSpec DeclaringType {
 943                         get {
 944                                 return declaringType;
 945                         }
 946                         set {
 947                                 declaringType = value;
 948                         }
 949                 }
 950
 951                 public IMemberDefinition MemberDefinition {
 952                         get {
 953                                 return definition;
 954                         }
 955                 }
 956
 957                 public Modifiers Modifiers {
 958                         get {
 959                                 return modifiers;
 960                         }
 961                         set {
 962                                 modifiers = value;
 963                         }
 964                 }
 965
 966                 public virtual string Name {
 967                         get {
 968                                 return definition.Name;
 969                         }
 970                 }
 971
 972                 public bool IsAbstract {
 973                         get { return (modifiers & Modifiers.ABSTRACT) != 0; }
 974                 }
 975
 976                 public bool IsAccessor {
 977                         get {
 978                                 return (state & StateFlags.IsAccessor) != 0;
 979                         }
 980                         set {
 981                                 state = value ? state | StateFlags.IsAccessor : state & ~StateFlags.IsAccessor;
 982                         }
 983                 }
 984
 985                 //
 986                 // Return true when this member is a generic in C# terms
 987                 // A nested non-generic type of generic type will return false
 988                 //
 989                 public bool IsGeneric {
 990                         get {
 991                                 return (state & StateFlags.IsGeneric) != 0;
 992                         }
 993                         set {
 994                                 state = value ? state | StateFlags.IsGeneric : state & ~StateFlags.IsGeneric;
 995                         }
 996                 }
 997
 998                 public bool IsPrivate {
 999                         get { return (modifiers & Modifiers.PRIVATE) != 0; }
1000                 }
1001
1002                 public bool IsStatic {
1003                         get {
1004                                 return (modifiers & Modifiers.STATIC) != 0;
1005                         }
1006                 }
1007
1008                 #endregion
1009
1010                 public virtual ObsoleteAttribute GetAttributeObsolete ()
1011                 {
1012                         if ((state & (StateFlags.Obsolete | StateFlags.Obsolete_Undetected)) == 0)
1013                                 return null;
1014
1015                         state &= ~StateFlags.Obsolete_Undetected;
1016
1017                         var oa = definition.GetAttributeObsolete ();
1018                         if (oa != null)
1019                                 state |= StateFlags.Obsolete;
1020
1021                         return oa;
1022                 }
1023
1024                 protected virtual bool IsNotCLSCompliant ()
1025                 {
1026                         return MemberDefinition.IsNotCLSCompliant ();
1027                 }
1028
1029                 public virtual string GetSignatureForError ()
1030                 {
1031                         var bf = MemberDefinition as Property.BackingField;
1032                         var name = bf == null ? Name : bf.OriginalName;
1033                         return DeclaringType.GetSignatureForError () + "." + name;
1034                 }
1035
1036                 public virtual MemberSpec InflateMember (TypeParameterInflator inflator)
1037                 {
1038                         var inflated = (MemberSpec) MemberwiseClone ();
1039                         inflated.declaringType = inflator.TypeInstance;
1040                         inflated.state |= StateFlags.PendingMetaInflate;
1041 #if DEBUG
1042                         if (inflated.ID > 0)
1043                                 inflated.ID = -inflated.ID;
1044 #endif
1045                         return inflated;
1046                 }
1047
1048                 //
1049                 // Returns member CLS compliance based on full member hierarchy
1050                 //
1051                 public bool IsCLSCompliant ()
1052                 {
1053                         if ((state & StateFlags.CLSCompliant_Undetected) != 0) {
1054                                 state &= ~StateFlags.CLSCompliant_Undetected;
1055
1056                                 if (IsNotCLSCompliant ())
1057                                         return false;
1058
1059                                 bool compliant;
1060                                 if (DeclaringType != null) {
1061                                         compliant = DeclaringType.IsCLSCompliant ();
1062                                 } else {
1063                                         // TODO: NEED AssemblySpec
1064                                         if (MemberDefinition.IsImported) {
1065                                                 var attr = MemberDefinition.Assembly.GetCustomAttributes (typeof (CLSCompliantAttribute), false);
1066                                                 compliant = attr.Length > 0 && ((CLSCompliantAttribute) attr[0]).IsCompliant;
1067                                         } else {
1068                                                 compliant = CodeGen.Assembly.IsClsCompliant;
1069                                         }
1070                                 }
1071
1072                                 if (compliant)
1073                                         state |= StateFlags.CLSCompliant;
1074                         }
1075
1076                         return (state & StateFlags.CLSCompliant) != 0;
1077                 }
1078
1079                 public bool IsConditionallyExcluded (Location loc)
1080                 {
1081                         if ((Kind & (MemberKind.Class | MemberKind.Method)) == 0)
1082                                 return false;
1083
1084                         var conditions = MemberDefinition.ConditionalConditions ();
1085                         if (conditions == null)
1086                                 return false;
1087
1088                         foreach (var condition in conditions) {
1089                                 if (loc.CompilationUnit.IsConditionalDefined (condition))
1090                                         return false;
1091                         }
1092
1093                         return true;
1094                 }
1095
1096                 public override string ToString ()
1097                 {
1098                         return GetSignatureForError ();
1099                 }
1100         }
1101
1102         //
1103         // Member details which are same between all member
1104         // specifications
1105         //
1106         public interface IMemberDefinition
1107         {
1108                 Assembly Assembly { get; }
1109                 string Name { get; }
1110                 bool IsImported { get; }
1111
1112                 string[] ConditionalConditions ();
1113                 ObsoleteAttribute GetAttributeObsolete ();
1114                 bool IsNotCLSCompliant ();
1115                 void SetIsAssigned ();
1116                 void SetIsUsed ();
1117         }
1118
1119         public interface IParametersMember : IInterfaceMemberSpec
1120         {
1121                 AParametersCollection Parameters { get; }
1122         }
1123
1124         public interface IInterfaceMemberSpec
1125         {
1126                 TypeSpec MemberType { get; }
1127         }
1128
1129         //
1130         // Base type container declaration. It exists to handle partial types
1131         // which share same definition (PartialContainer) but have different
1132         // resolve scopes
1133         //
1134         public abstract class DeclSpace : MemberCore {
1135                 /// <summary>
1136                 ///   This points to the actual definition that is being
1137                 ///   created with System.Reflection.Emit
1138                 /// </summary>
1139                 public TypeBuilder TypeBuilder;
1140
1141                 //
1142                 // This is the namespace in which this typecontainer
1143                 // was declared.  We use this to resolve names.
1144                 //
1145                 public NamespaceEntry NamespaceEntry;
1146
1147                 private Dictionary<string, FullNamedExpression> Cache = new Dictionary<string, FullNamedExpression> ();
1148
1149                 public readonly string Basename;
1150
1151                 protected Dictionary<string, MemberCore> defined_names;
1152
1153                 public TypeContainer PartialContainer;
1154
1155                 protected readonly bool is_generic;
1156                 readonly int count_type_params;
1157                 protected TypeParameter[] type_params;
1158                 TypeParameter[] type_param_list;
1159
1160                 //
1161                 // Whether we are Generic
1162                 //
1163                 public bool IsGeneric {
1164                         get {
1165                                 if (is_generic)
1166                                         return true;
1167                                 else if (Parent != null)
1168                                         return Parent.IsGeneric;
1169                                 else
1170                                         return false;
1171                         }
1172                 }
1173
1174                 static string[] attribute_targets = new string [] { "type" };
1175
1176                 public DeclSpace (NamespaceEntry ns, DeclSpace parent, MemberName name,
1177                                   Attributes attrs)
1178                         : base (parent, name, attrs)
1179                 {
1180                         NamespaceEntry = ns;
1181                         Basename = name.Basename;
1182                         defined_names = new Dictionary<string, MemberCore> ();
1183                         PartialContainer = null;
1184                         if (name.TypeArguments != null) {
1185                                 is_generic = true;
1186                                 count_type_params = name.TypeArguments.Count;
1187                         }
1188                         if (parent != null)
1189                                 count_type_params += parent.count_type_params;
1190                 }
1191
1192                 /// <summary>
1193                 /// Adds the member to defined_names table. It tests for duplications and enclosing name conflicts
1194                 /// </summary>
1195                 protected virtual bool AddToContainer (MemberCore symbol, string name)
1196                 {
1197                         MemberCore mc;
1198                         if (!defined_names.TryGetValue (name, out mc)) {
1199                                 defined_names.Add (name, symbol);
1200                                 return true;
1201                         }
1202
1203                         if (((mc.ModFlags | symbol.ModFlags) & Modifiers.COMPILER_GENERATED) != 0)
1204                                 return true;
1205
1206                         if (symbol.EnableOverloadChecks (mc))
1207                                 return true;
1208
1209                         InterfaceMemberBase im = mc as InterfaceMemberBase;
1210                         if (im != null && im.IsExplicitImpl)
1211                                 return true;
1212
1213                         Report.SymbolRelatedToPreviousError (mc);
1214                         if ((mc.ModFlags & Modifiers.PARTIAL) != 0 && (symbol is ClassOrStruct || symbol is Interface)) {
1215                                 Error_MissingPartialModifier (symbol);
1216                                 return false;
1217                         }
1218
1219                         if (this is ModuleContainer) {
1220                                 Report.Error (101, symbol.Location,
1221                                         "The namespace `{0}' already contains a definition for `{1}'",
1222                                         ((DeclSpace)symbol).NamespaceEntry.GetSignatureForError (), symbol.MemberName.Name);
1223                         } else if (symbol is TypeParameter) {
1224                                 Report.Error (692, symbol.Location,
1225                                         "Duplicate type parameter `{0}'", symbol.GetSignatureForError ());
1226                         } else {
1227                                 Report.Error (102, symbol.Location,
1228                                               "The type `{0}' already contains a definition for `{1}'",
1229                                               GetSignatureForError (), symbol.MemberName.Name);
1230                         }
1231
1232                         return false;
1233                 }
1234
1235                 protected void RemoveFromContainer (string name)
1236                 {
1237                         defined_names.Remove (name);
1238                 }
1239
1240                 /// <summary>
1241                 ///   Returns the MemberCore associated with a given name in the declaration
1242                 ///   space. It doesn't return method based symbols !!
1243                 /// </summary>
1244                 ///
1245                 public MemberCore GetDefinition (string name)
1246                 {
1247                         MemberCore mc = null;
1248                         defined_names.TryGetValue (name, out mc);
1249                         return mc;
1250                 }
1251
1252                 //
1253                 // root_types contains all the types.  All TopLevel types
1254                 // hence have a parent that points to `root_types', that is
1255                 // why there is a non-obvious test down here.
1256                 //
1257                 public bool IsTopLevel {
1258                         get { return (Parent != null && Parent.Parent == null); }
1259                 }
1260
1261                 public virtual bool IsUnmanagedType ()
1262                 {
1263                         return false;
1264                 }
1265
1266                 protected virtual TypeAttributes TypeAttr {
1267                         get { return Module.DefaultCharSetType; }
1268                 }
1269
1270                 /// <remarks>
1271                 ///  Should be overriten by the appropriate declaration space
1272                 /// </remarks>
1273                 public abstract TypeBuilder DefineType ();
1274
1275                 protected void Error_MissingPartialModifier (MemberCore type)
1276                 {
1277                         Report.Error (260, type.Location,
1278                                 "Missing partial modifier on declaration of type `{0}'. Another partial declaration of this type exists",
1279                                 type.GetSignatureForError ());
1280                 }
1281
1282                 public override string GetSignatureForError ()
1283                 {
1284                         return MemberName.GetSignatureForError ();
1285                 }
1286
1287                 public bool CheckAccessLevel (TypeSpec check_type)
1288                 {
1289                         TypeSpec tb = PartialContainer.Definition;
1290                         check_type = check_type.GetDefinition ();
1291
1292                         var check_attr = check_type.Modifiers & Modifiers.AccessibilityMask;
1293
1294                         switch (check_attr){
1295                         case Modifiers.PUBLIC:
1296                                 return true;
1297
1298                         case Modifiers.INTERNAL:
1299                                 return TypeManager.IsThisOrFriendAssembly (Assembly, check_type.Assembly);
1300
1301                         case Modifiers.PRIVATE:
1302                                 TypeSpec declaring = check_type.DeclaringType;
1303                                 return tb == declaring.GetDefinition () || TypeManager.IsNestedChildOf (tb, declaring);
1304
1305                         case Modifiers.PROTECTED:
1306                                 //
1307                                 // Only accessible to methods in current type or any subtypes
1308                                 //
1309                                 return TypeManager.IsNestedFamilyAccessible (tb, check_type.DeclaringType);
1310
1311                         case Modifiers.PROTECTED | Modifiers.INTERNAL:
1312                                 if (TypeManager.IsThisOrFriendAssembly (Assembly, check_type.Assembly))
1313                                         return true;
1314
1315                                 goto case Modifiers.PROTECTED;
1316                         }
1317
1318                         throw new NotImplementedException (check_attr.ToString ());
1319                 }
1320
1321                 private TypeSpec LookupNestedTypeInHierarchy (string name, int arity)
1322                 {
1323                         // TODO: GenericMethod only
1324                         if (PartialContainer == null)
1325                                 return null;
1326
1327                         // Has any nested type
1328                         // Does not work, because base type can have
1329                         //if (PartialContainer.Types == null)
1330                         //      return null;
1331
1332                         var container = PartialContainer.CurrentType;
1333
1334                         // Is not Root container
1335                         if (container == null)
1336                                 return null;
1337
1338                         var     t = MemberCache.FindNestedType (container, name, arity);
1339                         if (t == null)
1340                                 return null;
1341
1342                         // FIXME: Breaks error reporting
1343                         if (!CheckAccessLevel (t))
1344                                 return null;
1345
1346                         return t;
1347                 }
1348
1349                 //
1350                 // Public function used to locate types.
1351                 //
1352                 // Set 'ignore_cs0104' to true if you want to ignore cs0104 errors.
1353                 //
1354                 // Returns: Type or null if they type can not be found.
1355                 //
1356                 public override FullNamedExpression LookupNamespaceOrType (string name, int arity, Location loc, bool ignore_cs0104)
1357                 {
1358                         FullNamedExpression e;
1359                         if (arity == 0 && Cache.TryGetValue (name, out e))
1360                                 return e;
1361
1362                         e = null;
1363                         int errors = Report.Errors;
1364
1365                         if (arity == 0) {
1366                                 TypeParameter[] tp = CurrentTypeParameters;
1367                                 if (tp != null) {
1368                                         TypeParameter tparam = TypeParameter.FindTypeParameter (tp, name);
1369                                         if (tparam != null)
1370                                                 e = new TypeParameterExpr (tparam, Location.Null);
1371                                 }
1372                         }
1373
1374                         if (e == null) {
1375                                 TypeSpec t = LookupNestedTypeInHierarchy (name, arity);
1376
1377                                 if (t != null)
1378                                         e = new TypeExpression (t, Location.Null);
1379                                 else if (Parent != null)
1380                                         e = Parent.LookupNamespaceOrType (name, arity, loc, ignore_cs0104);
1381                                 else
1382                                         e = NamespaceEntry.LookupNamespaceOrType (name, arity, loc, ignore_cs0104);
1383                         }
1384
1385                         // TODO MemberCache: How to cache arity stuff ?
1386                         if (errors == Report.Errors && arity == 0)
1387                                 Cache [name] = e;
1388
1389                         return e;
1390                 }
1391
1392                 public override Assembly Assembly {
1393                         get { return Module.Assembly; }
1394                 }
1395
1396                 public virtual ModuleContainer Module {
1397                         get { return Parent.Module; }
1398                 }
1399
1400                 TypeParameter[] initialize_type_params ()
1401                 {
1402                         if (type_param_list != null)
1403                                 return type_param_list;
1404
1405                         DeclSpace the_parent = Parent;
1406                         if (this is GenericMethod)
1407                                 the_parent = null;
1408
1409                         var list = new List<TypeParameter> ();
1410                         if (the_parent != null && the_parent.IsGeneric) {
1411                                 // FIXME: move generics info out of DeclSpace
1412                                 TypeParameter[] parent_params = the_parent.TypeParameters;
1413                                 list.AddRange (parent_params);
1414                         }
1415
1416                         int count = type_params != null ? type_params.Length : 0;
1417                         for (int i = 0; i < count; i++) {
1418                                 TypeParameter param = type_params [i];
1419                                 list.Add (param);
1420                                 if (Parent.CurrentTypeParameters != null) {
1421                                         foreach (TypeParameter tp in Parent.CurrentTypeParameters) {
1422                                                 if (tp.Name != param.Name)
1423                                                         continue;
1424
1425                                                 Report.SymbolRelatedToPreviousError (tp.Location, null);
1426                                                 Report.Warning (693, 3, param.Location,
1427                                                         "Type parameter `{0}' has the same name as the type parameter from outer type `{1}'",
1428                                                         param.Name, Parent.GetSignatureForError ());
1429                                         }
1430                                 }
1431                         }
1432
1433                         type_param_list = new TypeParameter [list.Count];
1434                         list.CopyTo (type_param_list, 0);
1435                         return type_param_list;
1436                 }
1437
1438                 public virtual void SetParameterInfo (List<Constraints> constraints_list)
1439                 {
1440                         if (!is_generic) {
1441                                 if (constraints_list != null) {
1442                                         Report.Error (
1443                                                 80, Location, "Constraints are not allowed " +
1444                                                 "on non-generic declarations");
1445                                 }
1446
1447                                 return;
1448                         }
1449
1450                         TypeParameterName[] names = MemberName.TypeArguments.GetDeclarations ();
1451                         type_params = new TypeParameter [names.Length];
1452
1453                         //
1454                         // Register all the names
1455                         //
1456                         for (int i = 0; i < type_params.Length; i++) {
1457                                 TypeParameterName name = names [i];
1458
1459                                 Constraints constraints = null;
1460                                 if (constraints_list != null) {
1461                                         int total = constraints_list.Count;
1462                                         for (int ii = 0; ii < total; ++ii) {
1463                                                 Constraints constraints_at = (Constraints)constraints_list[ii];
1464                                                 // TODO: it is used by iterators only
1465                                                 if (constraints_at == null) {
1466                                                         constraints_list.RemoveAt (ii);
1467                                                         --total;
1468                                                         continue;
1469                                                 }
1470                                                 if (constraints_at.TypeParameter.Value == name.Name) {
1471                                                         constraints = constraints_at;
1472                                                         constraints_list.RemoveAt(ii);
1473                                                         break;
1474                                                 }
1475                                         }
1476                                 }
1477
1478                                 Variance variance = name.Variance;
1479                                 if (name.Variance != Variance.None && !(this is Delegate || this is Interface)) {
1480                                         Report.Error (1960, name.Location, "Variant type parameters can only be used with interfaces and delegates");
1481                                         variance = Variance.None;
1482                                 }
1483
1484                                 type_params [i] = new TypeParameter (
1485                                         Parent, i, new MemberName (name.Name, Location), constraints, name.OptAttributes, variance);
1486
1487                                 AddToContainer (type_params [i], name.Name);
1488                         }
1489
1490                         if (constraints_list != null && constraints_list.Count > 0) {
1491                                 foreach (Constraints constraint in constraints_list) {
1492                                         Report.Error(699, constraint.Location, "`{0}': A constraint references nonexistent type parameter `{1}'",
1493                                                 GetSignatureForError (), constraint.TypeParameter.Value);
1494                                 }
1495                         }
1496                 }
1497
1498                 protected TypeParameter[] TypeParameters {
1499                         get {
1500                                 if (!IsGeneric)
1501                                         throw new InvalidOperationException ();
1502                                 if ((PartialContainer != null) && (PartialContainer != this))
1503                                         return PartialContainer.TypeParameters;
1504                                 if (type_param_list == null)
1505                                         initialize_type_params ();
1506
1507                                 return type_param_list;
1508                         }
1509                 }
1510
1511                 public int CountTypeParameters {
1512                         get {
1513                                 return count_type_params;
1514                         }
1515                 }
1516
1517                 public override string[] ValidAttributeTargets {
1518                         get { return attribute_targets; }
1519                 }
1520
1521                 protected override bool VerifyClsCompliance ()
1522                 {
1523                         if (!base.VerifyClsCompliance ()) {
1524                                 return false;
1525                         }
1526
1527                         if (type_params != null) {
1528                                 foreach (TypeParameter tp in type_params) {
1529                                         tp.VerifyClsCompliance ();
1530                                 }
1531                         }
1532
1533                         return true;
1534                 }
1535         }
1536 }