mcs/gmcs/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 // Licensed under the terms of the GNU GPL
   8 //
   9 // (C) 2001 Ximian, Inc (http://www.ximian.com)
  10 //
  11 // TODO: Move the method verification stuff from the class.cs and interface.cs here
  12 //
  13
  14 using System;
  15 using System.Text;
  16 using System.Collections;
  17 using System.Globalization;
  18 using System.Reflection.Emit;
  19 using System.Reflection;
  20
  21 namespace Mono.CSharp {
  22
  23         public class MemberName {
  24                 public readonly string Name;
  25                 public readonly TypeArguments TypeArguments;
  26
  27                 public readonly MemberName Left;
  28
  29                 public static readonly MemberName Null = new MemberName ("");
  30
  31                 public MemberName (string name)
  32                 {
  33                         this.Name = name;
  34                 }
  35
  36                 public MemberName (string name, TypeArguments args)
  37                         : this (name)
  38                 {
  39                         this.TypeArguments = args;
  40                 }
  41
  42                 public MemberName (MemberName left, string name, TypeArguments args)
  43                         : this (name, args)
  44                 {
  45                         this.Left = left;
  46                 }
  47
  48                 public MemberName (MemberName left, MemberName right)
  49                         : this (left, right.Name, right.TypeArguments)
  50                 {
  51                 }
  52
  53                 public string GetName ()
  54                 {
  55                         if (Left != null)
  56                                 return Left.GetName () + "." + Name;
  57                         else
  58                                 return Name;
  59                 }
  60
  61                 public bool IsGeneric {
  62                         get {
  63                                 if (TypeArguments != null)
  64                                         return true;
  65                                 else if (Left != null)
  66                                         return Left.IsGeneric;
  67                                 else
  68                                         return false;
  69                         }
  70                 }
  71
  72                 public string GetName (bool is_generic)
  73                 {
  74                         string name = is_generic ? Basename : Name;
  75                         if (Left != null)
  76                                 return Left.GetName (is_generic) + "." + name;
  77                         else
  78                                 return name;
  79                 }
  80
  81                 public int CountTypeArguments {
  82                         get {
  83                                 if (TypeArguments == null)
  84                                         return 0;
  85                                 else
  86                                         return TypeArguments.Count;
  87                         }
  88                 }
  89
  90                 public string GetFullName ()
  91                 {
  92                         string full_name;
  93                         if (TypeArguments != null)
  94                                 full_name = Name + "<" + TypeArguments + ">";
  95                         else
  96                                 full_name = Name;
  97                         if (Left != null)
  98                                 return Left.GetFullName () + "." + full_name;
  99                         else
 100                                 return full_name;
 101                 }
 102
 103                 public static string MakeName (string name, TypeArguments args)
 104                 {
 105                         if (args == null)
 106                                 return name;
 107                         else
 108                                 return name + "`" + args.Count;
 109                 }
 110
 111                 public static string MakeName (string name, int count)
 112                 {
 113                         return name + "`" + count;
 114                 }
 115
 116                 public string GetTypeName ()
 117                 {
 118                         string suffix = "";
 119                         if (Left != null)
 120                                 return Left.GetTypeName () + "." +
 121                                         MakeName (Name, TypeArguments);
 122                         else
 123                                 return MakeName (Name, TypeArguments);
 124                 }
 125
 126                 protected bool IsUnbound {
 127                         get {
 128                                 if ((Left != null) && Left.IsUnbound)
 129                                         return true;
 130                                 else if (TypeArguments == null)
 131                                         return false;
 132                                 else
 133                                         return TypeArguments.IsUnbound;
 134                         }
 135                 }
 136
 137                 protected bool CheckUnbound (Location loc)
 138                 {
 139                         if ((Left != null) && !Left.CheckUnbound (loc))
 140                                 return false;
 141                         if ((TypeArguments != null) && !TypeArguments.IsUnbound) {
 142                                 Report.Error (1031, loc, "Type expected");
 143                                 return false;
 144                         }
 145
 146                         return true;
 147                 }
 148
 149                 public Expression GetTypeExpression (Location loc)
 150                 {
 151                         if (IsUnbound) {
 152                                 if (!CheckUnbound (loc))
 153                                         return null;
 154
 155                                 return new UnboundTypeExpression (GetTypeName ());
 156                         }
 157
 158                         if (Left != null) {
 159                                 Expression lexpr = Left.GetTypeExpression (loc);
 160
 161                                 return new MemberAccess (lexpr, Name, TypeArguments, loc);
 162                         } else {
 163                                 if (TypeArguments != null)
 164                                         return new ConstructedType (Name, TypeArguments, loc);
 165                                 else
 166                                         return new SimpleName (Name, loc);
 167                         }
 168                 }
 169
 170                 public string Basename {
 171                         get {
 172                                 if (TypeArguments != null)
 173                                         return MakeName (Name, TypeArguments);
 174                                 else
 175                                         return Name;
 176                         }
 177                 }
 178
 179                 public override string ToString ()
 180                 {
 181                         string full_name;
 182                         if (TypeArguments != null)
 183                                 full_name = Name + "<" + TypeArguments + ">";
 184                         else
 185                                 full_name = Name;
 186
 187                         if (Left != null)
 188                                 return Left + "." + full_name;
 189                         else
 190                                 return full_name;
 191                 }
 192         }
 193
 194         /// <summary>
 195         ///   Base representation for members.  This is used to keep track
 196         ///   of Name, Location and Modifier flags, and handling Attributes.
 197         /// </summary>
 198         public abstract class MemberCore : Attributable {
 199                 /// <summary>
 200                 ///   Public name
 201                 /// </summary>
 202                 public string Name;
 203
 204                 public readonly MemberName MemberName;
 205
 206                 /// <summary>
 207                 ///   Modifier flags that the user specified in the source code
 208                 /// </summary>
 209                 public int ModFlags;
 210
 211                 public readonly TypeContainer Parent;
 212
 213                 /// <summary>
 214                 ///   Location where this declaration happens
 215                 /// </summary>
 216                 public readonly Location Location;
 217
 218                 [Flags]
 219                 public enum Flags {
 220                         Obsolete_Undetected = 1,                // Obsolete attribute has not been detected yet
 221                         Obsolete = 1 << 1,                      // Type has obsolete attribute
 222                         ClsCompliance_Undetected = 1 << 2,      // CLS Compliance has not been detected yet
 223                         ClsCompliant = 1 << 3,                  // Type is CLS Compliant
 224                         CloseTypeCreated = 1 << 4,              // Tracks whether we have Closed the type
 225                         HasCompliantAttribute_Undetected = 1 << 5,      // Presence of CLSCompliantAttribute has not been detected
 226                         HasClsCompliantAttribute = 1 << 6,                      // Type has CLSCompliantAttribute
 227                         ClsCompliantAttributeTrue = 1 << 7,                     // Type has CLSCompliant (true)
 228                         Excluded_Undetected = 1 << 8,           // Conditional attribute has not been detected yet
 229                         Excluded = 1 << 9                                       // Method is conditional
 230
 231                 }
 232
 233                 /// <summary>
 234                 ///   MemberCore flags at first detected then cached
 235                 /// </summary>
 236                 protected Flags caching_flags;
 237
 238                 public MemberCore (TypeContainer parent, MemberName name, Attributes attrs,
 239                                    Location loc)
 240                         : base (attrs)
 241                 {
 242                         Parent = parent;
 243                         Name = name.GetName (!(this is GenericMethod) && !(this is Method));
 244                         MemberName = name;
 245                         Location = loc;
 246                         caching_flags = Flags.Obsolete_Undetected | Flags.ClsCompliance_Undetected | Flags.HasCompliantAttribute_Undetected | Flags.Excluded_Undetected;
 247                 }
 248
 249                 /// <summary>
 250                 /// Tests presence of ObsoleteAttribute and report proper error
 251                 /// </summary>
 252                 protected void CheckUsageOfObsoleteAttribute (Type type)
 253                 {
 254                         if (type == null)
 255                                 return;
 256
 257                         ObsoleteAttribute obsolete_attr = AttributeTester.GetObsoleteAttribute (type);
 258                         if (obsolete_attr == null)
 259                                 return;
 260
 261                         AttributeTester.Report_ObsoleteMessage (obsolete_attr, type.FullName, Location);
 262                 }
 263
 264                 public abstract bool Define ();
 265
 266                 //
 267                 // Returns full member name for error message
 268                 //
 269                 public virtual string GetSignatureForError ()
 270                 {
 271                         return Name;
 272                 }
 273
 274                 /// <summary>
 275                 /// Base Emit method. This is also entry point for CLS-Compliant verification.
 276                 /// </summary>
 277                 public virtual void Emit ()
 278                 {
 279                         VerifyObsoleteAttribute ();
 280
 281                         if (!RootContext.VerifyClsCompliance)
 282                                 return;
 283
 284                         VerifyClsCompliance (Parent);
 285                 }
 286
 287                 //
 288                 // Whehter is it ok to use an unsafe pointer in this type container
 289                 //
 290                 public bool UnsafeOK (DeclSpace parent)
 291                 {
 292                         //
 293                         // First check if this MemberCore modifier flags has unsafe set
 294                         //
 295                         if ((ModFlags & Modifiers.UNSAFE) != 0)
 296                                 return true;
 297
 298                         if (parent.UnsafeContext)
 299                                 return true;
 300
 301                         Expression.UnsafeError (Location);
 302                         return false;
 303                 }
 304
 305                 /// <summary>
 306                 /// Returns instance of ObsoleteAttribute for this MemberCore
 307                 /// </summary>
 308                 public ObsoleteAttribute GetObsoleteAttribute (DeclSpace ds)
 309                 {
 310                         // ((flags & (Flags.Obsolete_Undetected | Flags.Obsolete)) == 0) is slower, but why ?
 311                         if ((caching_flags & Flags.Obsolete_Undetected) == 0 && (caching_flags & Flags.Obsolete) == 0) {
 312                                 return null;
 313                         }
 314
 315                         caching_flags &= ~Flags.Obsolete_Undetected;
 316
 317                         if (OptAttributes == null)
 318                                 return null;
 319
 320                         // TODO: remove this allocation
 321                         EmitContext ec = new EmitContext (ds.Parent, ds, ds.Location,
 322                                 null, null, ds.ModFlags, false);
 323
 324                         Attribute obsolete_attr = OptAttributes.Search (TypeManager.obsolete_attribute_type, ec);
 325                         if (obsolete_attr == null)
 326                                 return null;
 327
 328                         ObsoleteAttribute obsolete = obsolete_attr.GetObsoleteAttribute (ds);
 329                         if (obsolete == null)
 330                                 return null;
 331
 332                         caching_flags |= Flags.Obsolete;
 333                         return obsolete;
 334                 }
 335
 336                 /// <summary>
 337                 /// Analyze whether CLS-Compliant verification must be execute for this MemberCore.
 338                 /// </summary>
 339                 public override bool IsClsCompliaceRequired (DeclSpace container)
 340                 {
 341                         if ((caching_flags & Flags.ClsCompliance_Undetected) == 0)
 342                                 return (caching_flags & Flags.ClsCompliant) != 0;
 343
 344                         if (GetClsCompliantAttributeValue (container) && IsExposedFromAssembly (container)) {
 345                                 caching_flags &= ~Flags.ClsCompliance_Undetected;
 346                                 caching_flags |= Flags.ClsCompliant;
 347                                 return true;
 348                         }
 349
 350                         caching_flags &= ~Flags.ClsCompliance_Undetected;
 351                         return false;
 352                 }
 353
 354                 /// <summary>
 355                 /// Returns true when MemberCore is exposed from assembly.
 356                 /// </summary>
 357                 protected bool IsExposedFromAssembly (DeclSpace ds)
 358                 {
 359                         if ((ModFlags & (Modifiers.PUBLIC | Modifiers.PROTECTED)) == 0)
 360                                 return false;
 361
 362                         DeclSpace parentContainer = ds;
 363                         while (parentContainer != null && parentContainer.ModFlags != 0) {
 364                                 if ((parentContainer.ModFlags & (Modifiers.PUBLIC | Modifiers.PROTECTED)) == 0)
 365                                         return false;
 366                                 parentContainer = parentContainer.Parent;
 367                         }
 368                         return true;
 369                 }
 370
 371                 /// <summary>
 372                 /// Resolve CLSCompliantAttribute value or gets cached value.
 373                 /// </summary>
 374                 bool GetClsCompliantAttributeValue (DeclSpace ds)
 375                 {
 376                         if (OptAttributes != null) {
 377                                 EmitContext ec = new EmitContext (ds.Parent, ds, ds.Location,
 378                                                                   null, null, ds.ModFlags, false);
 379                                 Attribute cls_attribute = OptAttributes.GetClsCompliantAttribute (ec);
 380                                 if (cls_attribute != null) {
 381                                         caching_flags |= Flags.HasClsCompliantAttribute;
 382                                         return cls_attribute.GetClsCompliantAttributeValue (ds);
 383                                 }
 384                         }
 385                         return ds.GetClsCompliantAttributeValue ();
 386                 }
 387
 388                 /// <summary>
 389                 /// Returns true if MemberCore is explicitly marked with CLSCompliantAttribute
 390                 /// </summary>
 391                 protected bool HasClsCompliantAttribute {
 392                         get {
 393                                 return (caching_flags & Flags.HasClsCompliantAttribute) != 0;
 394                         }
 395                 }
 396
 397                 /// <summary>
 398                 /// This method is used to testing error 3005 (Method or parameter name collision).
 399                 /// </summary>
 400                 protected abstract bool IsIdentifierClsCompliant (DeclSpace ds);
 401
 402                 /// <summary>
 403                 /// Common helper method for identifier and parameters CLS-Compliant testing.
 404                 /// When return false error 3005 is reported. True means no violation.
 405                 /// And error 3006 tests are peformed here because of speed.
 406                 /// </summary>
 407                 protected bool IsIdentifierAndParamClsCompliant (DeclSpace ds, string name, MemberInfo methodBuilder, Type[] paramTypes)
 408                 {
 409                         MemberList ml = ds.FindMembers (MemberTypes.Event | MemberTypes.Field | MemberTypes.Method | MemberTypes.Property,
 410                                 BindingFlags.Public | BindingFlags.Static | BindingFlags.Instance, System.Type.FilterNameIgnoreCase, name);
 411
 412                         if (ml.Count < 2)
 413                                 return true;
 414
 415                         bool error3006 = false;
 416                         for (int i = 0; i < ml.Count; ++i) {
 417                                 MemberInfo mi = ml [i];
 418                                 if (name == mi.Name) {
 419                                         MethodBase method = mi as MethodBase;
 420                                         if (method == null || method == methodBuilder || paramTypes == null || paramTypes.Length == 0)
 421                                                 continue;
 422
 423                                         if (AttributeTester.AreOverloadedMethodParamsClsCompliant (paramTypes, TypeManager.GetArgumentTypes (method))) {
 424                                                 error3006 = false;
 425                                                 continue;
 426                                         }
 427
 428                                         error3006 = true;
 429                                 }
 430
 431                                 // We need to test if member is not marked as CLSCompliant (false) and if type is not only internal
 432                                 // because BindingFlags.Public returns internal types too
 433                                 DeclSpace temp_ds = TypeManager.LookupDeclSpace (mi.DeclaringType);
 434
 435                                 // Type is external, we can get attribute directly
 436                                 if (temp_ds == null) {
 437                                         object[] cls_attribute = mi.GetCustomAttributes (TypeManager.cls_compliant_attribute_type, false);
 438                                         if (cls_attribute.Length == 1 && (!((CLSCompliantAttribute)cls_attribute[0]).IsCompliant))
 439                                                 continue;
 440                                 } else {
 441                                         string tmp_name = String.Concat (temp_ds.Name, '.', mi.Name);
 442
 443                                         MemberCore mc = temp_ds.GetDefinition (tmp_name) as MemberCore;
 444                                         if (!mc.IsClsCompliaceRequired (ds))
 445                                                 continue;
 446                                 }
 447
 448                                 for (int ii = 0; ii < ml.Count; ++ii) {
 449                                         mi = ml [ii];
 450                                         if (name == mi.Name)
 451                                                 continue;
 452                                         Report.SymbolRelatedToPreviousError (mi);
 453                                 }
 454
 455                                 if (error3006)
 456                                         Report.Error_T (3006, Location, GetSignatureForError ());
 457
 458                                 return error3006;
 459
 460                         }
 461                         return true;
 462                 }
 463
 464                 /// <summary>
 465                 /// The main virtual method for CLS-Compliant verifications.
 466                 /// The method returns true if member is CLS-Compliant and false if member is not
 467                 /// CLS-Compliant which means that CLS-Compliant tests are not necessary. A descendants override it
 468                 /// and add their extra verifications.
 469                 /// </summary>
 470                 protected virtual bool VerifyClsCompliance (DeclSpace ds)
 471                 {
 472                         if (!IsClsCompliaceRequired (ds)) {
 473                                 if (HasClsCompliantAttribute && !IsExposedFromAssembly (ds)) {
 474                                         Report.Warning_T (3019, Location, GetSignatureForError ());
 475                                 }
 476                                 return false;
 477                         }
 478
 479                         if (!CodeGen.Assembly.IsClsCompliant) {
 480                                 if (HasClsCompliantAttribute) {
 481                                         Report.Error_T (3014, Location, GetSignatureForError ());
 482                                 }
 483                         }
 484
 485                         int index = Name.LastIndexOf ('.');
 486                         if (Name [index > 0 ? index + 1 : 0] == '_') {
 487                                 Report.Error_T (3008, Location, GetSignatureForError () );
 488                         }
 489
 490                         if (!IsIdentifierClsCompliant (ds)) {
 491                                 Report.Error_T (3005, Location, GetSignatureForError ());
 492                         }
 493
 494                         return true;
 495                 }
 496
 497                 protected abstract void VerifyObsoleteAttribute ();
 498
 499         }
 500
 501         /// <summary>
 502         ///   Base class for structs, classes, enumerations and interfaces.
 503         /// </summary>
 504         /// <remarks>
 505         ///   They all create new declaration spaces.  This
 506         ///   provides the common foundation for managing those name
 507         ///   spaces.
 508         /// </remarks>
 509         public abstract class DeclSpace : MemberCore, IAlias {
 510                 /// <summary>
 511                 ///   This points to the actual definition that is being
 512                 ///   created with System.Reflection.Emit
 513                 /// </summary>
 514                 public TypeBuilder TypeBuilder;
 515
 516                 /// <summary>
 517                 ///   If we are a generic type, this is the type we are
 518                 ///   currently defining.  We need to lookup members on this
 519                 ///   instead of the TypeBuilder.
 520                 /// </summary>
 521                 public TypeExpr CurrentType;
 522
 523                 //
 524                 // This is the namespace in which this typecontainer
 525                 // was declared.  We use this to resolve names.
 526                 //
 527                 public NamespaceEntry NamespaceEntry;
 528
 529                 public Hashtable Cache = new Hashtable ();
 530
 531                 public string Basename;
 532
 533                 /// <summary>
 534                 ///   defined_names is used for toplevel objects
 535                 /// </summary>
 536                 protected Hashtable defined_names;
 537
 538                 readonly bool is_generic;
 539                 readonly int count_type_params;
 540
 541                 //
 542                 // Whether we are Generic
 543                 //
 544                 public bool IsGeneric {
 545                         get {
 546                                 if (is_generic)
 547                                         return true;
 548                                 else if (Parent != null)
 549                                         return Parent.IsGeneric;
 550                                 else
 551                                         return false;
 552                         }
 553                 }
 554
 555                 static string[] attribute_targets = new string [] { "type" };
 556
 557                 public DeclSpace (NamespaceEntry ns, TypeContainer parent, MemberName name,
 558                                   Attributes attrs, Location l)
 559                         : base (parent, name, attrs, l)
 560                 {
 561                         NamespaceEntry = ns;
 562                         Basename = name.Name;
 563                         defined_names = new Hashtable ();
 564                         if (name.TypeArguments != null) {
 565                                 is_generic = true;
 566                                 count_type_params = name.TypeArguments.Count;
 567                         }
 568                         if (parent != null)
 569                                 count_type_params += parent.count_type_params;
 570                 }
 571
 572                 public void RecordDecl ()
 573                 {
 574                         if ((NamespaceEntry != null) && (Parent == RootContext.Tree.Types))
 575                                 NamespaceEntry.DefineName (MemberName.Basename, this);
 576                 }
 577
 578                 /// <summary>
 579                 ///   The result value from adding an declaration into
 580                 ///   a struct or a class
 581                 /// </summary>
 582                 public enum AdditionResult {
 583                         /// <summary>
 584                         /// The declaration has been successfully
 585                         /// added to the declation space.
 586                         /// </summary>
 587                         Success,
 588
 589                         /// <summary>
 590                         ///   The symbol has already been defined.
 591                         /// </summary>
 592                         NameExists,
 593
 594                         /// <summary>
 595                         ///   Returned if the declation being added to the
 596                         ///   name space clashes with its container name.
 597                         ///
 598                         ///   The only exceptions for this are constructors
 599                         ///   and static constructors
 600                         /// </summary>
 601                         EnclosingClash,
 602
 603                         /// <summary>
 604                         ///   Returned if a constructor was created (because syntactically
 605                         ///   it looked like a constructor) but was not (because the name
 606                         ///   of the method is not the same as the container class
 607                         /// </summary>
 608                         NotAConstructor,
 609
 610                         /// <summary>
 611                         ///   This is only used by static constructors to emit the
 612                         ///   error 111, but this error for other things really
 613                         ///   happens at another level for other functions.
 614                         /// </summary>
 615                         MethodExists,
 616
 617                         /// <summary>
 618                         ///   Some other error.
 619                         /// </summary>
 620                         Error
 621                 }
 622
 623                 /// <summary>
 624                 ///   Returns a status code based purely on the name
 625                 ///   of the member being added
 626                 /// </summary>
 627                 protected AdditionResult IsValid (string basename, string name)
 628                 {
 629                         if (basename == Basename)
 630                                 return AdditionResult.EnclosingClash;
 631
 632                         if (defined_names.Contains (name))
 633                                 return AdditionResult.NameExists;
 634
 635                         return AdditionResult.Success;
 636                 }
 637
 638                 public static int length;
 639                 public static int small;
 640
 641                 /// <summary>
 642                 ///   Introduce @name into this declaration space and
 643                 ///   associates it with the object @o.  Note that for
 644                 ///   methods this will just point to the first method. o
 645                 /// </summary>
 646                 public void DefineName (string name, object o)
 647                 {
 648                         defined_names.Add (name, o);
 649
 650 #if DEBUGME
 651                         int p = name.LastIndexOf ('.');
 652                         int l = name.Length;
 653                         length += l;
 654                         small += l -p;
 655 #endif
 656                 }
 657
 658                 /// <summary>
 659                 ///   Returns the object associated with a given name in the declaration
 660                 ///   space.  This is the inverse operation of `DefineName'
 661                 /// </summary>
 662                 public object GetDefinition (string name)
 663                 {
 664                         return defined_names [name];
 665                 }
 666
 667                 bool in_transit = false;
 668
 669                 /// <summary>
 670                 ///   This function is used to catch recursive definitions
 671                 ///   in declarations.
 672                 /// </summary>
 673                 public bool InTransit {
 674                         get {
 675                                 return in_transit;
 676                         }
 677
 678                         set {
 679                                 in_transit = value;
 680                         }
 681                 }
 682
 683                 /// <summary>
 684                 ///   Looks up the alias for the name
 685                 /// </summary>
 686                 public IAlias LookupAlias (string name)
 687                 {
 688                         if (NamespaceEntry != null)
 689                                 return NamespaceEntry.LookupAlias (name);
 690                         else
 691                                 return null;
 692                 }
 693
 694                 //
 695                 // root_types contains all the types.  All TopLevel types
 696                 // hence have a parent that points to `root_types', that is
 697                 // why there is a non-obvious test down here.
 698                 //
 699                 public bool IsTopLevel {
 700                         get {
 701                                 if (Parent != null){
 702                                         if (Parent.Parent == null)
 703                                                 return true;
 704                                 }
 705                                 return false;
 706                         }
 707                 }
 708
 709                 public virtual void CloseType ()
 710                 {
 711                         if ((caching_flags & Flags.CloseTypeCreated) == 0){
 712                                 try {
 713                                         TypeBuilder.CreateType ();
 714                                 } catch {
 715                                         //
 716                                         // The try/catch is needed because
 717                                         // nested enumerations fail to load when they
 718                                         // are defined.
 719                                         //
 720                                         // Even if this is the right order (enumerations
 721                                         // declared after types).
 722                                         //
 723                                         // Note that this still creates the type and
 724                                         // it is possible to save it
 725                                 }
 726                                 caching_flags |= Flags.CloseTypeCreated;
 727                         }
 728                 }
 729
 730                 /// <remarks>
 731                 ///  Should be overriten by the appropriate declaration space
 732                 /// </remarks>
 733                 public abstract TypeBuilder DefineType ();
 734
 735                 /// <summary>
 736                 ///   Define all members, but don't apply any attributes or do anything which may
 737                 ///   access not-yet-defined classes.  This method also creates the MemberCache.
 738                 /// </summary>
 739                 public abstract bool DefineMembers (TypeContainer parent);
 740
 741                 //
 742                 // Whether this is an `unsafe context'
 743                 //
 744                 public bool UnsafeContext {
 745                         get {
 746                                 if ((ModFlags & Modifiers.UNSAFE) != 0)
 747                                         return true;
 748                                 if (Parent != null)
 749                                         return Parent.UnsafeContext;
 750                                 return false;
 751                         }
 752                 }
 753
 754                 public static string MakeFQN (string nsn, string name)
 755                 {
 756                         if (nsn == "")
 757                                 return name;
 758                         return String.Concat (nsn, ".", name);
 759                 }
 760
 761                 EmitContext type_resolve_ec;
 762                 EmitContext GetTypeResolveEmitContext (TypeContainer parent, Location loc)
 763                 {
 764                         type_resolve_ec = new EmitContext (parent, this, loc, null, null, ModFlags, false);
 765                         type_resolve_ec.ResolvingTypeTree = true;
 766
 767                         return type_resolve_ec;
 768                 }
 769
 770                 // <summary>
 771                 //    Looks up the type, as parsed into the expression `e'
 772                 // </summary>
 773                 public Type ResolveType (Expression e, bool silent, Location loc)
 774                 {
 775                         TypeExpr d = ResolveTypeExpr (e, silent, loc);
 776                         if (d == null)
 777                                 return null;
 778
 779                         return ResolveType (d, loc);
 780                 }
 781
 782                 public Type ResolveType (TypeExpr d, Location loc)
 783                 {
 784                         if (!d.CheckAccessLevel (this)) {
 785                                 Report.Error_T (122, loc, d.Name);
 786                                 return null;
 787                         }
 788
 789                         Type t = d.ResolveType (type_resolve_ec);
 790                         if (t == null)
 791                                 return null;
 792
 793                         if (d is UnboundTypeExpression)
 794                                 return t;
 795
 796                         TypeContainer tc = TypeManager.LookupTypeContainer (t);
 797                         if ((tc != null) && tc.IsGeneric) {
 798                                 if (!IsGeneric) {
 799                                         int tnum = TypeManager.GetNumberOfTypeArguments (t);
 800                                         Report.Error (305, loc,
 801                                                       "Using the generic type `{0}' " +
 802                                                       "requires {1} type arguments",
 803                                                       TypeManager.GetFullName (t), tnum);
 804                                         return null;
 805                                 }
 806
 807                                 ConstructedType ctype = new ConstructedType (
 808                                         t, TypeParameters, loc);
 809
 810                                 t = ctype.ResolveType (type_resolve_ec);
 811                         }
 812
 813                         return t;
 814                 }
 815
 816                 // <summary>
 817                 //    Resolves the expression `e' for a type, and will recursively define
 818                 //    types.
 819                 // </summary>
 820                 public TypeExpr ResolveTypeExpr (Expression e, bool silent, Location loc)
 821                 {
 822                         if (type_resolve_ec == null)
 823                                 type_resolve_ec = GetTypeResolveEmitContext (Parent, loc);
 824                         type_resolve_ec.loc = loc;
 825                         if (this is GenericMethod)
 826                                 type_resolve_ec.ContainerType = Parent.TypeBuilder;
 827                         else
 828                                 type_resolve_ec.ContainerType = TypeBuilder;
 829
 830                         int errors = Report.Errors;
 831
 832                         TypeExpr d = e.ResolveAsTypeTerminal (type_resolve_ec);
 833
 834                         if ((d != null) && (d.eclass == ExprClass.Type))
 835                                 return d;
 836
 837                         if (silent || (Report.Errors != errors))
 838                                 return null;
 839
 840                         if (e is SimpleName){
 841                                 SimpleName s = new SimpleName (((SimpleName) e).Name, loc);
 842                                 d = s.ResolveAsTypeTerminal (type_resolve_ec);
 843
 844                                 if ((d == null) || (d.Type == null)) {
 845                                         Report.Error (246, loc, "Cannot find type `{0}'", e);
 846                                         return null;
 847                                 }
 848
 849                                 int num_args = TypeManager.GetNumberOfTypeArguments (d.Type);
 850
 851                                 if (num_args == 0) {
 852                                         Report.Error (308, loc,
 853                                                       "The non-generic type `{0}' cannot " +
 854                                                       "be used with type arguments.",
 855                                                       TypeManager.CSharpName (d.Type));
 856                                         return null;
 857                                 }
 858
 859                                 Report.Error (305, loc,
 860                                               "Using the generic type `{0}' " +
 861                                               "requires {1} type arguments",
 862                                               TypeManager.GetFullName (d.Type), num_args);
 863                                 return null;
 864                         }
 865
 866                         Report.Error (246, loc, "Cannot find type `{0}'", e);
 867                         return null;
 868                 }
 869
 870                 public bool CheckAccessLevel (Type check_type)
 871                 {
 872                         TypeBuilder tb;
 873                         if (this is GenericMethod)
 874                                 tb = Parent.TypeBuilder;
 875                         else
 876                                 tb = TypeBuilder;
 877
 878                         if (check_type.IsGenericInstance)
 879                                 check_type = check_type.GetGenericTypeDefinition ();
 880
 881                         if (check_type == tb)
 882                                 return true;
 883
 884                         if (check_type.IsGenericParameter)
 885                                 return true; // FIXME
 886
 887                         TypeAttributes check_attr = check_type.Attributes & TypeAttributes.VisibilityMask;
 888
 889                         //
 890                         // Broken Microsoft runtime, return public for arrays, no matter what
 891                         // the accessibility is for their underlying class, and they return
 892                         // NonPublic visibility for pointers
 893                         //
 894                         if (check_type.IsArray || check_type.IsPointer)
 895                                 return CheckAccessLevel (TypeManager.GetElementType (check_type));
 896
 897                         switch (check_attr){
 898                         case TypeAttributes.Public:
 899                                 return true;
 900
 901                         case TypeAttributes.NotPublic:
 902
 903                                 // In same cases is null.
 904                                 if (TypeBuilder == null)
 905                                         return true;
 906
 907                                 //
 908                                 // This test should probably use the declaringtype.
 909                                 //
 910                                 return check_type.Assembly == TypeBuilder.Assembly;
 911
 912                         case TypeAttributes.NestedPublic:
 913                                 return true;
 914
 915                         case TypeAttributes.NestedPrivate:
 916                                 string check_type_name = check_type.FullName;
 917                                 string type_name = tb.FullName;
 918
 919                                 int cio = check_type_name.LastIndexOf ('+');
 920                                 string container = check_type_name.Substring (0, cio);
 921
 922                                 //
 923                                 // Check if the check_type is a nested class of the current type
 924                                 //
 925                                 if (check_type_name.StartsWith (type_name + "+")){
 926                                         return true;
 927                                 }
 928
 929                                 if (type_name.StartsWith (container)){
 930                                         return true;
 931                                 }
 932
 933                                 return false;
 934
 935                         case TypeAttributes.NestedFamily:
 936                                 //
 937                                 // Only accessible to methods in current type or any subtypes
 938                                 //
 939                                 return FamilyAccessible (tb, check_type);
 940
 941                         case TypeAttributes.NestedFamANDAssem:
 942                                 return (check_type.Assembly == tb.Assembly) &&
 943                                         FamilyAccessible (tb, check_type);
 944
 945                         case TypeAttributes.NestedFamORAssem:
 946                                 return (check_type.Assembly == tb.Assembly) ||
 947                                         FamilyAccessible (tb, check_type);
 948
 949                         case TypeAttributes.NestedAssembly:
 950                                 return check_type.Assembly == tb.Assembly;
 951                         }
 952
 953                         Console.WriteLine ("HERE: " + check_attr);
 954                         return false;
 955
 956                 }
 957
 958                 protected bool FamilyAccessible (TypeBuilder tb, Type check_type)
 959                 {
 960                         Type declaring = check_type.DeclaringType;
 961                         if (tb.IsSubclassOf (declaring))
 962                                 return true;
 963
 964                         string check_type_name = check_type.FullName;
 965
 966                         int cio = check_type_name.LastIndexOf ('+');
 967                         string container = check_type_name.Substring (0, cio);
 968
 969                         //
 970                         // Check if the check_type is a nested class of the current type
 971                         //
 972                         if (check_type_name.StartsWith (container + "+"))
 973                                 return true;
 974
 975                         return false;
 976                 }
 977
 978                 // Access level of a type.
 979                 const int X = 1;
 980                 enum AccessLevel { // Each column represents `is this scope larger or equal to Blah scope'
 981                         // Public    Assembly   Protected
 982                         Protected           = (0 << 0) | (0 << 1) | (X << 2),
 983                         Public              = (X << 0) | (X << 1) | (X << 2),
 984                         Private             = (0 << 0) | (0 << 1) | (0 << 2),
 985                         Internal            = (0 << 0) | (X << 1) | (0 << 2),
 986                         ProtectedOrInternal = (0 << 0) | (X << 1) | (X << 2),
 987                 }
 988
 989                 static AccessLevel GetAccessLevelFromModifiers (int flags)
 990                 {
 991                         if ((flags & Modifiers.INTERNAL) != 0) {
 992
 993                                 if ((flags & Modifiers.PROTECTED) != 0)
 994                                         return AccessLevel.ProtectedOrInternal;
 995                                 else
 996                                         return AccessLevel.Internal;
 997
 998                         } else if ((flags & Modifiers.PROTECTED) != 0)
 999                                 return AccessLevel.Protected;
1000                         else if ((flags & Modifiers.PRIVATE) != 0)
1001                                 return AccessLevel.Private;
1002                         else
1003                                 return AccessLevel.Public;
1004                 }
1005
1006                 // What is the effective access level of this?
1007                 // TODO: Cache this?
1008                 AccessLevel EffectiveAccessLevel {
1009                         get {
1010                                 AccessLevel myAccess = GetAccessLevelFromModifiers (ModFlags);
1011                                 if (!IsTopLevel && (Parent != null))
1012                                         return myAccess & Parent.EffectiveAccessLevel;
1013                                 return myAccess;
1014                         }
1015                 }
1016
1017                 // Return the access level for type `t'
1018                 static AccessLevel TypeEffectiveAccessLevel (Type t)
1019                 {
1020                         if (t.IsPublic)
1021                                 return AccessLevel.Public;
1022                         if (t.IsNestedPrivate)
1023                                 return AccessLevel.Private;
1024                         if (t.IsNotPublic)
1025                                 return AccessLevel.Internal;
1026
1027                         // By now, it must be nested
1028                         AccessLevel parentLevel = TypeEffectiveAccessLevel (t.DeclaringType);
1029
1030                         if (t.IsNestedPublic)
1031                                 return parentLevel;
1032                         if (t.IsNestedAssembly)
1033                                 return parentLevel & AccessLevel.Internal;
1034                         if (t.IsNestedFamily)
1035                                 return parentLevel & AccessLevel.Protected;
1036                         if (t.IsNestedFamORAssem)
1037                                 return parentLevel & AccessLevel.ProtectedOrInternal;
1038                         if (t.IsNestedFamANDAssem)
1039                                 throw new NotImplementedException ("NestedFamANDAssem not implemented, cant make this kind of type from c# anyways");
1040
1041                         // nested private is taken care of
1042
1043                         throw new Exception ("I give up, what are you?");
1044                 }
1045
1046                 //
1047                 // This answers `is the type P, as accessible as a member M which has the
1048                 // accessability @flags which is declared as a nested member of the type T, this declspace'
1049                 //
1050                 public bool AsAccessible (Type p, int flags)
1051                 {
1052                         if (p.IsGenericParameter)
1053                                 return true; // FIXME
1054
1055                         //
1056                         // 1) if M is private, its accessability is the same as this declspace.
1057                         // we already know that P is accessible to T before this method, so we
1058                         // may return true.
1059                         //
1060
1061                         if ((flags & Modifiers.PRIVATE) != 0)
1062                                 return true;
1063
1064                         while (p.IsArray || p.IsPointer || p.IsByRef)
1065                                 p = TypeManager.GetElementType (p);
1066
1067                         AccessLevel pAccess = TypeEffectiveAccessLevel (p);
1068                         AccessLevel mAccess = this.EffectiveAccessLevel &
1069                                 GetAccessLevelFromModifiers (flags);
1070
1071                         // for every place from which we can access M, we must
1072                         // be able to access P as well. So, we want
1073                         // For every bit in M and P, M_i -> P_1 == true
1074                         // or, ~ (M -> P) == 0 <-> ~ ( ~M | P) == 0
1075
1076                         return ~ (~ mAccess | pAccess) == 0;
1077                 }
1078
1079                 static DoubleHash dh = new DoubleHash (1000);
1080
1081                 Type DefineTypeAndParents (DeclSpace tc)
1082                 {
1083                         DeclSpace container = tc.Parent;
1084
1085                         if (container.TypeBuilder == null && container.Name != "")
1086                                 DefineTypeAndParents (container);
1087
1088                         return tc.DefineType ();
1089                 }
1090
1091                 Type LookupInterfaceOrClass (string ns, string name, out bool error)
1092                 {
1093                         DeclSpace parent;
1094                         Type t;
1095                         object r;
1096
1097                         error = false;
1098
1099                         if (dh.Lookup (ns, name, out r))
1100                                 return (Type) r;
1101                         else {
1102                                 if (ns != ""){
1103                                         if (Namespace.IsNamespace (ns)){
1104                                                 string fullname = (ns != "") ? ns + "." + name : name;
1105                                                 t = TypeManager.LookupType (fullname);
1106                                         } else
1107                                                 t = null;
1108                                 } else
1109                                         t = TypeManager.LookupType (name);
1110                         }
1111
1112                         if (t != null) {
1113                                 dh.Insert (ns, name, t);
1114                                 return t;
1115                         }
1116
1117                         //
1118                         // In case we are fed a composite name, normalize it.
1119                         //
1120                         int p = name.LastIndexOf ('.');
1121                         if (p != -1){
1122                                 ns = MakeFQN (ns, name.Substring (0, p));
1123                                 name = name.Substring (p+1);
1124                         }
1125
1126                         parent = RootContext.Tree.LookupByNamespace (ns, name);
1127                         if (parent == null) {
1128                                 dh.Insert (ns, name, null);
1129                                 return null;
1130                         }
1131
1132                         t = DefineTypeAndParents (parent);
1133                         if (t == null){
1134                                 error = true;
1135                                 return null;
1136                         }
1137
1138                         dh.Insert (ns, name, t);
1139                         return t;
1140                 }
1141
1142                 public static void Error_AmbiguousTypeReference (Location loc, string name, string t1, string t2)
1143                 {
1144                         Report.Error (104, loc,
1145                                       "`{0}' is an ambiguous reference ({1} or {2})",
1146                                       name, t1, t2);
1147                 }
1148
1149                 public Type FindNestedType (Location loc, string name,
1150                                             out DeclSpace containing_ds)
1151                 {
1152                         Type t;
1153                         bool error;
1154
1155                         containing_ds = this;
1156                         while (containing_ds != null){
1157                                 Type container_type = containing_ds.TypeBuilder;
1158                                 Type current_type = container_type;
1159
1160                                 while (current_type != null && current_type != TypeManager.object_type) {
1161                                         string pre = current_type.FullName;
1162
1163                                         t = LookupInterfaceOrClass (pre, name, out error);
1164                                         if (error)
1165                                                 return null;
1166
1167                                         if ((t != null) && containing_ds.CheckAccessLevel (t))
1168                                                 return t;
1169
1170                                         current_type = current_type.BaseType;
1171                                 }
1172                                 containing_ds = containing_ds.Parent;
1173                         }
1174
1175                         return null;
1176                 }
1177
1178                 /// <summary>
1179                 ///   GetType is used to resolve type names at the DeclSpace level.
1180                 ///   Use this to lookup class/struct bases, interface bases or
1181                 ///   delegate type references
1182                 /// </summary>
1183                 ///
1184                 /// <remarks>
1185                 ///   Contrast this to LookupType which is used inside method bodies to
1186                 ///   lookup types that have already been defined.  GetType is used
1187                 ///   during the tree resolution process and potentially define
1188                 ///   recursively the type
1189                 /// </remarks>
1190                 public Type FindType (Location loc, string name)
1191                 {
1192                         Type t;
1193                         bool error;
1194
1195                         //
1196                         // For the case the type we are looking for is nested within this one
1197                         // or is in any base class
1198                         //
1199                         DeclSpace containing_ds = this;
1200
1201                         while (containing_ds != null){
1202                                 Type container_type = containing_ds.TypeBuilder;
1203                                 Type current_type = container_type;
1204
1205                                 while (current_type != null && current_type != TypeManager.object_type) {
1206                                         string pre = current_type.FullName;
1207
1208                                         t = LookupInterfaceOrClass (pre, name, out error);
1209                                         if (error)
1210                                                 return null;
1211
1212                                         if ((t != null) && containing_ds.CheckAccessLevel (t))
1213                                                 return t;
1214
1215                                         current_type = current_type.BaseType;
1216                                 }
1217                                 containing_ds = containing_ds.Parent;
1218                         }
1219
1220                         //
1221                         // Attempt to lookup the class on our namespace and all it's implicit parents
1222                         //
1223                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.ImplicitParent) {
1224                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
1225                                 if (error)
1226                                         return null;
1227
1228                                 if (t != null)
1229                                         return t;
1230                         }
1231
1232                         //
1233                         // Attempt to do a direct unqualified lookup
1234                         //
1235                         t = LookupInterfaceOrClass ("", name, out error);
1236                         if (error)
1237                                 return null;
1238
1239                         if (t != null)
1240                                 return t;
1241
1242                         //
1243                         // Attempt to lookup the class on any of the `using'
1244                         // namespaces
1245                         //
1246
1247                         for (NamespaceEntry ns = NamespaceEntry; ns != null; ns = ns.Parent){
1248
1249                                 t = LookupInterfaceOrClass (ns.FullName, name, out error);
1250                                 if (error)
1251                                         return null;
1252
1253                                 if (t != null)
1254                                         return t;
1255
1256                                 if (name.IndexOf ('.') > 0)
1257                                         continue;
1258
1259                                 IAlias alias_value = ns.LookupAlias (name);
1260                                 if (alias_value != null) {
1261                                         t = LookupInterfaceOrClass ("", alias_value.Name, out error);
1262                                         if (error)
1263                                                 return null;
1264
1265                                         if (t != null)
1266                                                 return t;
1267                                 }
1268
1269                                 //
1270                                 // Now check the using clause list
1271                                 //
1272                                 Type match = null;
1273                                 foreach (Namespace using_ns in ns.GetUsingTable ()) {
1274                                         match = LookupInterfaceOrClass (using_ns.Name, name, out error);
1275                                         if (error)
1276                                                 return null;
1277
1278                                         if (match != null) {
1279                                                 if (t != null){
1280                                                         if (CheckAccessLevel (match)) {
1281                                                                 Error_AmbiguousTypeReference (loc, name, t.FullName, match.FullName);
1282                                                                 return null;
1283                                                         }
1284                                                         continue;
1285                                                 }
1286
1287                                                 t = match;
1288                                         }
1289                                 }
1290                                 if (t != null)
1291                                         return t;
1292                         }
1293
1294                         //Report.Error (246, Location, "Can not find type `"+name+"'");
1295                         return null;
1296                 }
1297
1298                 /// <remarks>
1299                 ///   This function is broken and not what you're looking for.  It should only
1300                 ///   be used while the type is still being created since it doesn't use the cache
1301                 ///   and relies on the filter doing the member name check.
1302                 /// </remarks>
1303                 public abstract MemberList FindMembers (MemberTypes mt, BindingFlags bf,
1304                                                         MemberFilter filter, object criteria);
1305
1306                 /// <remarks>
1307                 ///   If we have a MemberCache, return it.  This property may return null if the
1308                 ///   class doesn't have a member cache or while it's still being created.
1309                 /// </remarks>
1310                 public abstract MemberCache MemberCache {
1311                         get;
1312                 }
1313
1314                 public override void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder cb)
1315                 {
1316                         try {
1317                                 TypeBuilder.SetCustomAttribute (cb);
1318                         } catch (System.ArgumentException e) {
1319                                 Report.Warning (-21, a.Location,
1320                                                 "The CharSet named property on StructLayout\n"+
1321                                                 "\tdoes not work correctly on Microsoft.NET\n"+
1322                                                 "\tYou might want to remove the CharSet declaration\n"+
1323                                                 "\tor compile using the Mono runtime instead of the\n"+
1324                                                 "\tMicrosoft .NET runtime\n"+
1325                                                 "\tThe runtime gave the error: " + e);
1326                         }
1327                 }
1328
1329                 /// <summary>
1330                 /// Goes through class hierarchy and get value of first CLSCompliantAttribute that found.
1331                 /// If no is attribute exists then return assembly CLSCompliantAttribute.
1332                 /// </summary>
1333                 public bool GetClsCompliantAttributeValue ()
1334                 {
1335                         if ((caching_flags & Flags.HasCompliantAttribute_Undetected) == 0)
1336                                 return (caching_flags & Flags.ClsCompliantAttributeTrue) != 0;
1337
1338                         caching_flags &= ~Flags.HasCompliantAttribute_Undetected;
1339
1340                         if (OptAttributes != null) {
1341                                 EmitContext ec = new EmitContext (Parent, this, Location,
1342                                                                   null, null, ModFlags, false);
1343                                 Attribute cls_attribute = OptAttributes.GetClsCompliantAttribute (ec);
1344                                 if (cls_attribute != null) {
1345                                         caching_flags |= Flags.HasClsCompliantAttribute;
1346                                         if (cls_attribute.GetClsCompliantAttributeValue (this)) {
1347                                                 caching_flags |= Flags.ClsCompliantAttributeTrue;
1348                                                 return true;
1349                                         }
1350                                         return false;
1351                                 }
1352                         }
1353
1354                         if (Parent == null) {
1355                                 if (CodeGen.Assembly.IsClsCompliant) {
1356                                         caching_flags |= Flags.ClsCompliantAttributeTrue;
1357                                         return true;
1358                                 }
1359                                 return false;
1360                         }
1361
1362                         if (Parent.GetClsCompliantAttributeValue ()) {
1363                                 caching_flags |= Flags.ClsCompliantAttributeTrue;
1364                                 return true;
1365                         }
1366                         return false;
1367                 }
1368
1369
1370                 // Tests container name for CLS-Compliant name (differing only in case)
1371                 // Possible optimalization: search in same namespace only
1372                 protected override bool IsIdentifierClsCompliant (DeclSpace ds)
1373                 {
1374                         int l = Name.Length;
1375
1376                         if (Namespace.LookupNamespace (NamespaceEntry.FullName, false) != null) {
1377                                 // Seek through all imported types
1378                                 foreach (string type_name in TypeManager.all_imported_types.Keys)
1379                                 {
1380                                         if (l != type_name.Length)
1381                                                 continue;
1382
1383                                         if (String.Compare (Name, type_name, true, CultureInfo.InvariantCulture) == 0 &&
1384                                                 AttributeTester.IsClsCompliant (TypeManager.all_imported_types [type_name] as Type)) {
1385                                                 Report.SymbolRelatedToPreviousError ((Type)TypeManager.all_imported_types [type_name]);
1386                                                 return false;
1387                                 }
1388                         }
1389                         }
1390
1391                         // Seek through generated types
1392                         foreach (string name in RootContext.Tree.Decls.Keys) {
1393                                 if (l != name.Length)
1394                                         continue;
1395
1396                                 if (String.Compare (Name, name, true, CultureInfo.InvariantCulture) == 0) {
1397
1398                                         if (Name == name)
1399                                                 continue;
1400
1401                                         DeclSpace found_ds = RootContext.Tree.Decls[name] as DeclSpace;
1402                                         if (found_ds.IsClsCompliaceRequired (found_ds.Parent)) {
1403                                                 Report.SymbolRelatedToPreviousError (found_ds.Location, found_ds.GetSignatureForError ());
1404                                                 return false;
1405                                 }
1406                         }
1407                         }
1408
1409                         return true;
1410                 }
1411
1412                 //
1413                 // Extensions for generics
1414                 //
1415                 TypeParameter[] type_params;
1416                 TypeParameter[] type_param_list;
1417
1418                 protected string GetInstantiationName ()
1419                 {
1420                         StringBuilder sb = new StringBuilder (Name);
1421                         sb.Append ("<");
1422                         for (int i = 0; i < type_param_list.Length; i++) {
1423                                 if (i > 0)
1424                                         sb.Append (",");
1425                                 sb.Append (type_param_list [i].Name);
1426                         }
1427                         sb.Append (">");
1428                         return sb.ToString ();
1429                 }
1430
1431                 bool check_type_parameter (ArrayList list, int start, string name)
1432                 {
1433                         for (int i = 0; i < start; i++) {
1434                                 TypeParameter param = (TypeParameter) list [i];
1435
1436                                 if (param.Name != name)
1437                                         continue;
1438
1439                                 if (RootContext.WarningLevel >= 3)
1440                                         Report.Warning (
1441                                                 693, Location,
1442                                                 "Type parameter `{0}' has same name " +
1443                                                 "as type parameter from outer type `{1}'",
1444                                                 name, Parent.GetInstantiationName ());
1445
1446                                 return false;
1447                         }
1448
1449                         return true;
1450                 }
1451
1452                 TypeParameter[] initialize_type_params ()
1453                 {
1454                         if (type_param_list != null)
1455                                 return type_param_list;
1456
1457                         DeclSpace the_parent = Parent;
1458                         if (this is GenericMethod)
1459                                 the_parent = null;
1460
1461                         int start = 0;
1462                         TypeParameter[] parent_params = null;
1463                         if ((the_parent != null) && the_parent.IsGeneric) {
1464                                 parent_params = the_parent.initialize_type_params ();
1465                                 start = parent_params != null ? parent_params.Length : 0;
1466                         }
1467
1468                         ArrayList list = new ArrayList ();
1469                         if (parent_params != null)
1470                                 list.AddRange (parent_params);
1471
1472                         int count = type_params != null ? type_params.Length : 0;
1473                         for (int i = 0; i < count; i++) {
1474                                 TypeParameter param = type_params [i];
1475                                 check_type_parameter (list, start, param.Name);
1476                                 list.Add (param);
1477                         }
1478
1479                         type_param_list = new TypeParameter [list.Count];
1480                         list.CopyTo (type_param_list, 0);
1481                         return type_param_list;
1482                 }
1483
1484                 public AdditionResult SetParameterInfo (ArrayList constraints_list)
1485                 {
1486                         if (!is_generic) {
1487                                 if (constraints_list != null) {
1488                                         Report.Error (
1489                                                 80, Location, "Contraints are not allowed " +
1490                                                 "on non-generic declarations");
1491                                         return AdditionResult.Error;
1492                                 }
1493
1494                                 return AdditionResult.Success;
1495                         }
1496
1497                         string[] names = MemberName.TypeArguments.GetDeclarations ();
1498                         type_params = new TypeParameter [names.Length];
1499
1500                         //
1501                         // Register all the names
1502                         //
1503                         for (int i = 0; i < type_params.Length; i++) {
1504                                 string name = names [i];
1505
1506                                 AdditionResult res = IsValid (name, name);
1507
1508                                 if (res != AdditionResult.Success)
1509                                         return res;
1510
1511                                 Constraints constraints = null;
1512                                 if (constraints_list != null) {
1513                                         foreach (Constraints constraint in constraints_list) {
1514                                                 if (constraint.TypeParameter == name) {
1515                                                         constraints = constraint;
1516                                                         break;
1517                                                 }
1518                                         }
1519                                 }
1520
1521                                 type_params [i] = new TypeParameter (name, constraints, Location);
1522
1523                                 DefineName (name, type_params [i]);
1524                         }
1525
1526                         return AdditionResult.Success;
1527                 }
1528
1529                 public TypeParameter[] TypeParameters {
1530                         get {
1531                                 if (!IsGeneric)
1532                                         throw new InvalidOperationException ();
1533                                 if (type_param_list == null)
1534                                         initialize_type_params ();
1535
1536                                 return type_param_list;
1537                         }
1538                 }
1539
1540                 protected TypeParameter[] CurrentTypeParameters {
1541                         get {
1542                                 if (!IsGeneric)
1543                                         throw new InvalidOperationException ();
1544                                 if (type_params != null)
1545                                         return type_params;
1546                                 else
1547                                         return new TypeParameter [0];
1548                         }
1549                 }
1550
1551                 public int CountTypeParameters {
1552                         get {
1553                                 return count_type_params;
1554                         }
1555                 }
1556
1557                 public TypeParameterExpr LookupGeneric (string name, Location loc)
1558                 {
1559                         if (!IsGeneric)
1560                                 return null;
1561
1562                         foreach (TypeParameter type_param in CurrentTypeParameters) {
1563                                 if (type_param.Name != name)
1564                                         continue;
1565
1566                                 return new TypeParameterExpr (type_param, loc);
1567                         }
1568
1569                         if (Parent != null)
1570                                 return Parent.LookupGeneric (name, loc);
1571
1572                         return null;
1573                 }
1574
1575                 bool IAlias.IsType {
1576                         get { return true; }
1577                 }
1578
1579                 string IAlias.Name {
1580                         get { return Name; }
1581                 }
1582
1583                 TypeExpr IAlias.Type
1584                 {
1585                         get {
1586                                 if (TypeBuilder == null)
1587                                         throw new InvalidOperationException ();
1588
1589                                 if (CurrentType != null)
1590                                         return CurrentType;
1591
1592                                 return new TypeExpression (TypeBuilder, Location);
1593                         }
1594                 }
1595
1596                 protected override string[] ValidAttributeTargets {
1597                         get {
1598                                 return attribute_targets;
1599                         }
1600                 }
1601         }
1602
1603         /// <summary>
1604         ///   This is a readonly list of MemberInfo's.
1605         /// </summary>
1606         public class MemberList : IList {
1607                 public readonly IList List;
1608                 int count;
1609
1610                 /// <summary>
1611                 ///   Create a new MemberList from the given IList.
1612                 /// </summary>
1613                 public MemberList (IList list)
1614                 {
1615                         if (list != null)
1616                                 this.List = list;
1617                         else
1618                                 this.List = new ArrayList ();
1619                         count = List.Count;
1620                 }
1621
1622                 /// <summary>
1623                 ///   Concatenate the ILists `first' and `second' to a new MemberList.
1624                 /// </summary>
1625                 public MemberList (IList first, IList second)
1626                 {
1627                         ArrayList list = new ArrayList ();
1628                         list.AddRange (first);
1629                         list.AddRange (second);
1630                         count = list.Count;
1631                         List = list;
1632                 }
1633
1634                 public static readonly MemberList Empty = new MemberList (new ArrayList ());
1635
1636                 /// <summary>
1637                 ///   Cast the MemberList into a MemberInfo[] array.
1638                 /// </summary>
1639                 /// <remarks>
1640                 ///   This is an expensive operation, only use it if it's really necessary.
1641                 /// </remarks>
1642                 public static explicit operator MemberInfo [] (MemberList list)
1643                 {
1644                         Timer.StartTimer (TimerType.MiscTimer);
1645                         MemberInfo [] result = new MemberInfo [list.Count];
1646                         list.CopyTo (result, 0);
1647                         Timer.StopTimer (TimerType.MiscTimer);
1648                         return result;
1649                 }
1650
1651                 // ICollection
1652
1653                 public int Count {
1654                         get {
1655                                 return count;
1656                         }
1657                 }
1658
1659                 public bool IsSynchronized {
1660                         get {
1661                                 return List.IsSynchronized;
1662                         }
1663                 }
1664
1665                 public object SyncRoot {
1666                         get {
1667                                 return List.SyncRoot;
1668                         }
1669                 }
1670
1671                 public void CopyTo (Array array, int index)
1672                 {
1673                         List.CopyTo (array, index);
1674                 }
1675
1676                 // IEnumerable
1677
1678                 public IEnumerator GetEnumerator ()
1679                 {
1680                         return List.GetEnumerator ();
1681                 }
1682
1683                 // IList
1684
1685                 public bool IsFixedSize {
1686                         get {
1687                                 return true;
1688                         }
1689                 }
1690
1691                 public bool IsReadOnly {
1692                         get {
1693                                 return true;
1694                         }
1695                 }
1696
1697                 object IList.this [int index] {
1698                         get {
1699                                 return List [index];
1700                         }
1701
1702                         set {
1703                                 throw new NotSupportedException ();
1704                         }
1705                 }
1706
1707                 // FIXME: try to find out whether we can avoid the cast in this indexer.
1708                 public MemberInfo this [int index] {
1709                         get {
1710                                 return (MemberInfo) List [index];
1711                         }
1712                 }
1713
1714                 public int Add (object value)
1715                 {
1716                         throw new NotSupportedException ();
1717                 }
1718
1719                 public void Clear ()
1720                 {
1721                         throw new NotSupportedException ();
1722                 }
1723
1724                 public bool Contains (object value)
1725                 {
1726                         return List.Contains (value);
1727                 }
1728
1729                 public int IndexOf (object value)
1730                 {
1731                         return List.IndexOf (value);
1732                 }
1733
1734                 public void Insert (int index, object value)
1735                 {
1736                         throw new NotSupportedException ();
1737                 }
1738
1739                 public void Remove (object value)
1740                 {
1741                         throw new NotSupportedException ();
1742                 }
1743
1744                 public void RemoveAt (int index)
1745                 {
1746                         throw new NotSupportedException ();
1747                 }
1748         }
1749
1750         /// <summary>
1751         ///   This interface is used to get all members of a class when creating the
1752         ///   member cache.  It must be implemented by all DeclSpace derivatives which
1753         ///   want to support the member cache and by TypeHandle to get caching of
1754         ///   non-dynamic types.
1755         /// </summary>
1756         public interface IMemberContainer {
1757                 /// <summary>
1758                 ///   The name of the IMemberContainer.  This is only used for
1759                 ///   debugging purposes.
1760                 /// </summary>
1761                 string Name {
1762                         get;
1763                 }
1764
1765                 /// <summary>
1766                 ///   The type of this IMemberContainer.
1767                 /// </summary>
1768                 Type Type {
1769                         get;
1770                 }
1771
1772                 /// <summary>
1773                 ///   Returns the IMemberContainer of the parent class or null if this
1774                 ///   is an interface or TypeManger.object_type.
1775                 ///   This is used when creating the member cache for a class to get all
1776                 ///   members from the parent class.
1777                 /// </summary>
1778                 IMemberContainer Parent {
1779                         get;
1780                 }
1781
1782                 /// <summary>
1783                 ///   Whether this is an interface.
1784                 /// </summary>
1785                 bool IsInterface {
1786                         get;
1787                 }
1788
1789                 /// <summary>
1790                 ///   Returns all members of this class with the corresponding MemberTypes
1791                 ///   and BindingFlags.
1792                 /// </summary>
1793                 /// <remarks>
1794                 ///   When implementing this method, make sure not to return any inherited
1795                 ///   members and check the MemberTypes and BindingFlags properly.
1796                 ///   Unfortunately, System.Reflection is lame and doesn't provide a way to
1797                 ///   get the BindingFlags (static/non-static,public/non-public) in the
1798                 ///   MemberInfo class, but the cache needs this information.  That's why
1799                 ///   this method is called multiple times with different BindingFlags.
1800                 /// </remarks>
1801                 MemberList GetMembers (MemberTypes mt, BindingFlags bf);
1802
1803                 /// <summary>
1804                 ///   Return the container's member cache.
1805                 /// </summary>
1806                 MemberCache MemberCache {
1807                         get;
1808                 }
1809         }
1810
1811         /// <summary>
1812         ///   The MemberCache is used by dynamic and non-dynamic types to speed up
1813         ///   member lookups.  It has a member name based hash table; it maps each member
1814         ///   name to a list of CacheEntry objects.  Each CacheEntry contains a MemberInfo
1815         ///   and the BindingFlags that were initially used to get it.  The cache contains
1816         ///   all members of the current class and all inherited members.  If this cache is
1817         ///   for an interface types, it also contains all inherited members.
1818         ///
1819         ///   There are two ways to get a MemberCache:
1820         ///   * if this is a dynamic type, lookup the corresponding DeclSpace and then
1821         ///     use the DeclSpace.MemberCache property.
1822         ///   * if this not a dynamic type, call TypeHandle.GetTypeHandle() to get a
1823         ///     TypeHandle instance for the type and then use TypeHandle.MemberCache.
1824         /// </summary>
1825         public class MemberCache {
1826                 public readonly IMemberContainer Container;
1827                 protected Hashtable member_hash;
1828                 protected Hashtable method_hash;
1829
1830                 /// <summary>
1831                 ///   Create a new MemberCache for the given IMemberContainer `container'.
1832                 /// </summary>
1833                 public MemberCache (IMemberContainer container)
1834                 {
1835                         this.Container = container;
1836
1837                         Timer.IncrementCounter (CounterType.MemberCache);
1838                         Timer.StartTimer (TimerType.CacheInit);
1839
1840
1841
1842                         // If we have a parent class (we have a parent class unless we're
1843                         // TypeManager.object_type), we deep-copy its MemberCache here.
1844                         if (Container.IsInterface) {
1845                                 MemberCache parent;
1846
1847                                 if (Container.Parent != null)
1848                                         parent = Container.Parent.MemberCache;
1849                                 else
1850                                         parent = TypeHandle.ObjectType.MemberCache;
1851                                 member_hash = SetupCacheForInterface (parent);
1852                         } else if (Container.Parent != null)
1853                                 member_hash = SetupCache (Container.Parent.MemberCache);
1854                         else
1855                                 member_hash = new Hashtable ();
1856
1857                         // If this is neither a dynamic type nor an interface, create a special
1858                         // method cache with all declared and inherited methods.
1859                         Type type = container.Type;
1860                         if (!(type is TypeBuilder) && !type.IsInterface && !type.IsGenericParameter) {
1861                                 method_hash = new Hashtable ();
1862                                 AddMethods (type);
1863                         }
1864
1865                         // Add all members from the current class.
1866                         AddMembers (Container);
1867
1868                         Timer.StopTimer (TimerType.CacheInit);
1869                 }
1870
1871                 /// <summary>
1872                 ///   Bootstrap this member cache by doing a deep-copy of our parent.
1873                 /// </summary>
1874                 Hashtable SetupCache (MemberCache parent)
1875                 {
1876                         Hashtable hash = new Hashtable ();
1877
1878                         IDictionaryEnumerator it = parent.member_hash.GetEnumerator ();
1879                         while (it.MoveNext ()) {
1880                                 hash [it.Key] = ((ArrayList) it.Value).Clone ();
1881                         }
1882
1883                         return hash;
1884                 }
1885
1886
1887                 /// <summary>
1888                 ///   Add the contents of `new_hash' to `hash'.
1889                 /// </summary>
1890                 void AddHashtable (Hashtable hash, MemberCache cache)
1891                 {
1892                         Hashtable new_hash = cache.member_hash;
1893                         IDictionaryEnumerator it = new_hash.GetEnumerator ();
1894                         while (it.MoveNext ()) {
1895                                 ArrayList list = (ArrayList) hash [it.Key];
1896                                 if (list == null)
1897                                         hash [it.Key] = list = new ArrayList ();
1898
1899                                 foreach (CacheEntry entry in (ArrayList) it.Value) {
1900                                         if (entry.Container != cache.Container)
1901                                                 break;
1902                                         list.Add (entry);
1903                                 }
1904                         }
1905                 }
1906
1907                 /// <summary>
1908                 ///   Bootstrap the member cache for an interface type.
1909                 ///   Type.GetMembers() won't return any inherited members for interface types,
1910                 ///   so we need to do this manually.  Interfaces also inherit from System.Object.
1911                 /// </summary>
1912                 Hashtable SetupCacheForInterface (MemberCache parent)
1913                 {
1914                         Hashtable hash = SetupCache (parent);
1915                         Type [] ifaces = TypeManager.GetInterfaces (Container.Type);
1916
1917                         foreach (Type itype in ifaces) {
1918                                 IMemberContainer iface_container =
1919                                         TypeManager.LookupMemberContainer (itype);
1920
1921                                 MemberCache iface_cache = iface_container.MemberCache;
1922
1923                                 AddHashtable (hash, iface_cache);
1924                         }
1925
1926                         return hash;
1927                 }
1928
1929                 /// <summary>
1930                 ///   Add all members from class `container' to the cache.
1931                 /// </summary>
1932                 void AddMembers (IMemberContainer container)
1933                 {
1934                         // We need to call AddMembers() with a single member type at a time
1935                         // to get the member type part of CacheEntry.EntryType right.
1936                         AddMembers (MemberTypes.Constructor, container);
1937                         AddMembers (MemberTypes.Field, container);
1938                         AddMembers (MemberTypes.Method, container);
1939                         AddMembers (MemberTypes.Property, container);
1940                         AddMembers (MemberTypes.Event, container);
1941                         // Nested types are returned by both Static and Instance searches.
1942                         AddMembers (MemberTypes.NestedType,
1943                                     BindingFlags.Static | BindingFlags.Public, container);
1944                         AddMembers (MemberTypes.NestedType,
1945                                     BindingFlags.Static | BindingFlags.NonPublic, container);
1946                 }
1947
1948                 void AddMembers (MemberTypes mt, IMemberContainer container)
1949                 {
1950                         AddMembers (mt, BindingFlags.Static | BindingFlags.Public, container);
1951                         AddMembers (mt, BindingFlags.Static | BindingFlags.NonPublic, container);
1952                         AddMembers (mt, BindingFlags.Instance | BindingFlags.Public, container);
1953                         AddMembers (mt, BindingFlags.Instance | BindingFlags.NonPublic, container);
1954                 }
1955
1956                 /// <summary>
1957                 ///   Add all members from class `container' with the requested MemberTypes and
1958                 ///   BindingFlags to the cache.  This method is called multiple times with different
1959                 ///   MemberTypes and BindingFlags.
1960                 /// </summary>
1961                 void AddMembers (MemberTypes mt, BindingFlags bf, IMemberContainer container)
1962                 {
1963                         MemberList members = container.GetMembers (mt, bf);
1964
1965                         foreach (MemberInfo member in members) {
1966                                 string name = member.Name;
1967
1968                                 int pos = name.IndexOf ('<');
1969                                 if (pos > 0)
1970                                         name = name.Substring (0, pos);
1971
1972                                 // We use a name-based hash table of ArrayList's.
1973                                 ArrayList list = (ArrayList) member_hash [name];
1974                                 if (list == null) {
1975                                         list = new ArrayList ();
1976                                         member_hash.Add (name, list);
1977                                 }
1978
1979                                 // When this method is called for the current class, the list will
1980                                 // already contain all inherited members from our parent classes.
1981                                 // We cannot add new members in front of the list since this'd be an
1982                                 // expensive operation, that's why the list is sorted in reverse order
1983                                 // (ie. members from the current class are coming last).
1984                                 list.Add (new CacheEntry (container, member, mt, bf));
1985                         }
1986                 }
1987
1988                 /// <summary>
1989                 ///   Add all declared and inherited methods from class `type' to the method cache.
1990                 /// </summary>
1991                 void AddMethods (Type type)
1992                 {
1993                         AddMethods (BindingFlags.Static | BindingFlags.Public |
1994                                     BindingFlags.FlattenHierarchy, type);
1995                         AddMethods (BindingFlags.Static | BindingFlags.NonPublic |
1996                                     BindingFlags.FlattenHierarchy, type);
1997                         AddMethods (BindingFlags.Instance | BindingFlags.Public, type);
1998                         AddMethods (BindingFlags.Instance | BindingFlags.NonPublic, type);
1999                 }
2000
2001                 void AddMethods (BindingFlags bf, Type type)
2002                 {
2003                         MemberInfo [] members = type.GetMethods (bf);
2004
2005                         Array.Reverse (members);
2006
2007                         foreach (MethodBase member in members) {
2008                                 string name = member.Name;
2009
2010                                 // We use a name-based hash table of ArrayList's.
2011                                 ArrayList list = (ArrayList) method_hash [name];
2012                                 if (list == null) {
2013                                         list = new ArrayList ();
2014                                         method_hash.Add (name, list);
2015                                 }
2016
2017                                 // Unfortunately, the elements returned by Type.GetMethods() aren't
2018                                 // sorted so we need to do this check for every member.
2019                                 BindingFlags new_bf = bf;
2020                                 if (member.DeclaringType == type)
2021                                         new_bf |= BindingFlags.DeclaredOnly;
2022
2023                                 list.Add (new CacheEntry (Container, member, MemberTypes.Method, new_bf));
2024                         }
2025                 }
2026
2027                 /// <summary>
2028                 ///   Compute and return a appropriate `EntryType' magic number for the given
2029                 ///   MemberTypes and BindingFlags.
2030                 /// </summary>
2031                 protected static EntryType GetEntryType (MemberTypes mt, BindingFlags bf)
2032                 {
2033                         EntryType type = EntryType.None;
2034
2035                         if ((mt & MemberTypes.Constructor) != 0)
2036                                 type |= EntryType.Constructor;
2037                         if ((mt & MemberTypes.Event) != 0)
2038                                 type |= EntryType.Event;
2039                         if ((mt & MemberTypes.Field) != 0)
2040                                 type |= EntryType.Field;
2041                         if ((mt & MemberTypes.Method) != 0)
2042                                 type |= EntryType.Method;
2043                         if ((mt & MemberTypes.Property) != 0)
2044                                 type |= EntryType.Property;
2045                         // Nested types are returned by static and instance searches.
2046                         if ((mt & MemberTypes.NestedType) != 0)
2047                                 type |= EntryType.NestedType | EntryType.Static | EntryType.Instance;
2048
2049                         if ((bf & BindingFlags.Instance) != 0)
2050                                 type |= EntryType.Instance;
2051                         if ((bf & BindingFlags.Static) != 0)
2052                                 type |= EntryType.Static;
2053                         if ((bf & BindingFlags.Public) != 0)
2054                                 type |= EntryType.Public;
2055                         if ((bf & BindingFlags.NonPublic) != 0)
2056                                 type |= EntryType.NonPublic;
2057                         if ((bf & BindingFlags.DeclaredOnly) != 0)
2058                                 type |= EntryType.Declared;
2059
2060                         return type;
2061                 }
2062
2063                 /// <summary>
2064                 ///   The `MemberTypes' enumeration type is a [Flags] type which means that it may
2065                 ///   denote multiple member types.  Returns true if the given flags value denotes a
2066                 ///   single member types.
2067                 /// </summary>
2068                 public static bool IsSingleMemberType (MemberTypes mt)
2069                 {
2070                         switch (mt) {
2071                         case MemberTypes.Constructor:
2072                         case MemberTypes.Event:
2073                         case MemberTypes.Field:
2074                         case MemberTypes.Method:
2075                         case MemberTypes.Property:
2076                         case MemberTypes.NestedType:
2077                                 return true;
2078
2079                         default:
2080                                 return false;
2081                         }
2082                 }
2083
2084                 /// <summary>
2085                 ///   We encode the MemberTypes and BindingFlags of each members in a "magic"
2086                 ///   number to speed up the searching process.
2087                 /// </summary>
2088                 [Flags]
2089                 protected enum EntryType {
2090                         None            = 0x000,
2091
2092                         Instance        = 0x001,
2093                         Static          = 0x002,
2094                         MaskStatic      = Instance|Static,
2095
2096                         Public          = 0x004,
2097                         NonPublic       = 0x008,
2098                         MaskProtection  = Public|NonPublic,
2099
2100                         Declared        = 0x010,
2101
2102                         Constructor     = 0x020,
2103                         Event           = 0x040,
2104                         Field           = 0x080,
2105                         Method          = 0x100,
2106                         Property        = 0x200,
2107                         NestedType      = 0x400,
2108
2109                         MaskType        = Constructor|Event|Field|Method|Property|NestedType
2110                 }
2111
2112                 protected struct CacheEntry {
2113                         public readonly IMemberContainer Container;
2114                         public readonly EntryType EntryType;
2115                         public readonly MemberInfo Member;
2116
2117                         public CacheEntry (IMemberContainer container, MemberInfo member,
2118                                            MemberTypes mt, BindingFlags bf)
2119                         {
2120                                 this.Container = container;
2121                                 this.Member = member;
2122                                 this.EntryType = GetEntryType (mt, bf);
2123                         }
2124                 }
2125
2126                 /// <summary>
2127                 ///   This is called each time we're walking up one level in the class hierarchy
2128                 ///   and checks whether we can abort the search since we've already found what
2129                 ///   we were looking for.
2130                 /// </summary>
2131                 protected bool DoneSearching (ArrayList list)
2132                 {
2133                         //
2134                         // We've found exactly one member in the current class and it's not
2135                         // a method or constructor.
2136                         //
2137                         if (list.Count == 1 && !(list [0] is MethodBase))
2138                                 return true;
2139
2140                         //
2141                         // Multiple properties: we query those just to find out the indexer
2142                         // name
2143                         //
2144                         if ((list.Count > 0) && (list [0] is PropertyInfo))
2145                                 return true;
2146
2147                         return false;
2148                 }
2149
2150                 /// <summary>
2151                 ///   Looks up members with name `name'.  If you provide an optional
2152                 ///   filter function, it'll only be called with members matching the
2153                 ///   requested member name.
2154                 ///
2155                 ///   This method will try to use the cache to do the lookup if possible.
2156                 ///
2157                 ///   Unlike other FindMembers implementations, this method will always
2158                 ///   check all inherited members - even when called on an interface type.
2159                 ///
2160                 ///   If you know that you're only looking for methods, you should use
2161                 ///   MemberTypes.Method alone since this speeds up the lookup a bit.
2162                 ///   When doing a method-only search, it'll try to use a special method
2163                 ///   cache (unless it's a dynamic type or an interface) and the returned
2164                 ///   MemberInfo's will have the correct ReflectedType for inherited methods.
2165                 ///   The lookup process will automatically restart itself in method-only
2166                 ///   search mode if it discovers that it's about to return methods.
2167                 /// </summary>
2168                 ArrayList global = new ArrayList ();
2169                 bool using_global = false;
2170
2171                 static MemberInfo [] emptyMemberInfo = new MemberInfo [0];
2172
2173                 public MemberInfo [] FindMembers (MemberTypes mt, BindingFlags bf, string name,
2174                                                MemberFilter filter, object criteria)
2175                 {
2176                         if (using_global)
2177                                 throw new Exception ();
2178
2179                         bool declared_only = (bf & BindingFlags.DeclaredOnly) != 0;
2180                         bool method_search = mt == MemberTypes.Method;
2181                         // If we have a method cache and we aren't already doing a method-only search,
2182                         // then we restart a method search if the first match is a method.
2183                         bool do_method_search = !method_search && (method_hash != null);
2184
2185                         ArrayList applicable;
2186
2187                         // If this is a method-only search, we try to use the method cache if
2188                         // possible; a lookup in the method cache will return a MemberInfo with
2189                         // the correct ReflectedType for inherited methods.
2190
2191                         if (method_search && (method_hash != null))
2192                                 applicable = (ArrayList) method_hash [name];
2193                         else
2194                                 applicable = (ArrayList) member_hash [name];
2195
2196                         if (applicable == null)
2197                                 return emptyMemberInfo;
2198
2199                         //
2200                         // 32  slots gives 53 rss/54 size
2201                         // 2/4 slots gives 55 rss
2202                         //
2203                         // Strange: from 25,000 calls, only 1,800
2204                         // are above 2.  Why does this impact it?
2205                         //
2206                         global.Clear ();
2207                         using_global = true;
2208
2209                         Timer.StartTimer (TimerType.CachedLookup);
2210
2211                         EntryType type = GetEntryType (mt, bf);
2212
2213                         IMemberContainer current = Container;
2214
2215
2216                         // `applicable' is a list of all members with the given member name `name'
2217                         // in the current class and all its parent classes.  The list is sorted in
2218                         // reverse order due to the way how the cache is initialy created (to speed
2219                         // things up, we're doing a deep-copy of our parent).
2220
2221                         for (int i = applicable.Count-1; i >= 0; i--) {
2222                                 CacheEntry entry = (CacheEntry) applicable [i];
2223
2224                                 // This happens each time we're walking one level up in the class
2225                                 // hierarchy.  If we're doing a DeclaredOnly search, we must abort
2226                                 // the first time this happens (this may already happen in the first
2227                                 // iteration of this loop if there are no members with the name we're
2228                                 // looking for in the current class).
2229                                 if (entry.Container != current) {
2230                                         if (declared_only || DoneSearching (global))
2231                                                 break;
2232
2233                                         current = entry.Container;
2234                                 }
2235
2236                                 // Is the member of the correct type ?
2237                                 if ((entry.EntryType & type & EntryType.MaskType) == 0)
2238                                         continue;
2239
2240                                 // Is the member static/non-static ?
2241                                 if ((entry.EntryType & type & EntryType.MaskStatic) == 0)
2242                                         continue;
2243
2244                                 // Apply the filter to it.
2245                                 if (filter (entry.Member, criteria)) {
2246                                         if ((entry.EntryType & EntryType.MaskType) != EntryType.Method)
2247                                                 do_method_search = false;
2248                                         global.Add (entry.Member);
2249                                 }
2250                         }
2251
2252                         Timer.StopTimer (TimerType.CachedLookup);
2253
2254                         // If we have a method cache and we aren't already doing a method-only
2255                         // search, we restart in method-only search mode if the first match is
2256                         // a method.  This ensures that we return a MemberInfo with the correct
2257                         // ReflectedType for inherited methods.
2258                         if (do_method_search && (global.Count > 0)){
2259                                 using_global = false;
2260
2261                                 return FindMembers (MemberTypes.Method, bf, name, filter, criteria);
2262                         }
2263
2264                         using_global = false;
2265                         MemberInfo [] copy = new MemberInfo [global.Count];
2266                         global.CopyTo (copy);
2267                         return copy;
2268                 }
2269
2270                 //
2271                 // This finds the method or property for us to override. invocationType is the type where
2272                 // the override is going to be declared, name is the name of the method/property, and
2273                 // paramTypes is the parameters, if any to the method or property
2274                 //
2275                 // Because the MemberCache holds members from this class and all the base classes,
2276                 // we can avoid tons of reflection stuff.
2277                 //
2278                 public MemberInfo FindMemberToOverride (Type invocationType, string name, Type [] paramTypes, bool is_property)
2279                 {
2280                         ArrayList applicable;
2281                         if (method_hash != null && !is_property)
2282                                 applicable = (ArrayList) method_hash [name];
2283                         else
2284                                 applicable = (ArrayList) member_hash [name];
2285
2286                         if (applicable == null)
2287                                 return null;
2288                         //
2289                         // Walk the chain of methods, starting from the top.
2290                         //
2291                         for (int i = applicable.Count - 1; i >= 0; i--) {
2292                                 CacheEntry entry = (CacheEntry) applicable [i];
2293
2294                                 if ((entry.EntryType & (is_property ? (EntryType.Property | EntryType.Field) : EntryType.Method)) == 0)
2295                                         continue;
2296
2297                                 PropertyInfo pi = null;
2298                                 MethodInfo mi = null;
2299                                 FieldInfo fi = null;
2300                                 Type [] cmpAttrs = null;
2301
2302                                 if (is_property) {
2303                                         if ((entry.EntryType & EntryType.Field) != 0) {
2304                                                 fi = (FieldInfo)entry.Member;
2305
2306                                                 // TODO: For this case we ignore member type
2307                                                 //fb = TypeManager.GetField (fi);
2308                                                 //cmpAttrs = new Type[] { fb.MemberType };
2309                                         } else {
2310                                                 pi = (PropertyInfo) entry.Member;
2311                                                 cmpAttrs = TypeManager.GetArgumentTypes (pi);
2312                                         }
2313                                 } else {
2314                                         mi = (MethodInfo) entry.Member;
2315                                         cmpAttrs = TypeManager.GetArgumentTypes (mi);
2316                                 }
2317
2318                                 if (fi != null) {
2319                                         // TODO: Almost duplicate !
2320                                         // Check visibility
2321                                         switch (fi.Attributes & FieldAttributes.FieldAccessMask) {
2322                                                 case FieldAttributes.Private:
2323                                                         //
2324                                                         // A private method is Ok if we are a nested subtype.
2325                                                         // The spec actually is not very clear about this, see bug 52458.
2326                                                         //
2327                                                         if (invocationType != entry.Container.Type &
2328                                                                 TypeManager.IsNestedChildOf (invocationType, entry.Container.Type))
2329                                                                 continue;
2330
2331                                                         break;
2332                                                 case FieldAttributes.FamANDAssem:
2333                                                 case FieldAttributes.Assembly:
2334                                                         //
2335                                                         // Check for assembly methods
2336                                                         //
2337                                                         if (mi.DeclaringType.Assembly != CodeGen.Assembly.Builder)
2338                                                                 continue;
2339                                                         break;
2340                                         }
2341                                         return entry.Member;
2342                                 }
2343
2344                                 //
2345                                 // Check the arguments
2346                                 //
2347                                 if (cmpAttrs.Length != paramTypes.Length)
2348                                         continue;
2349
2350                                 for (int j = cmpAttrs.Length - 1; j >= 0; j --) {
2351                                         if (!paramTypes [j].Equals (cmpAttrs [j]))
2352                                                 goto next;
2353                                 }
2354
2355                                 //
2356                                 // get one of the methods because this has the visibility info.
2357                                 //
2358                                 if (is_property) {
2359                                         mi = pi.GetGetMethod (true);
2360                                         if (mi == null)
2361                                                 mi = pi.GetSetMethod (true);
2362                                 }
2363
2364                                 //
2365                                 // Check visibility
2366                                 //
2367                                 switch (mi.Attributes & MethodAttributes.MemberAccessMask) {
2368                                 case MethodAttributes.Private:
2369                                         //
2370                                         // A private method is Ok if we are a nested subtype.
2371                                         // The spec actually is not very clear about this, see bug 52458.
2372                                         //
2373                                         if (invocationType == entry.Container.Type ||
2374                                             TypeManager.IsNestedChildOf (invocationType, entry.Container.Type))
2375                                                 return entry.Member;
2376
2377                                         break;
2378                                 case MethodAttributes.FamANDAssem:
2379                                 case MethodAttributes.Assembly:
2380                                         //
2381                                         // Check for assembly methods
2382                                         //
2383                                         if (mi.DeclaringType.Assembly == CodeGen.Assembly.Builder)
2384                                                 return entry.Member;
2385
2386                                         break;
2387                                 default:
2388                                         //
2389                                         // A protected method is ok, because we are overriding.
2390                                         // public is always ok.
2391                                         //
2392                                         return entry.Member;
2393                                 }
2394                         next:
2395                                 ;
2396                         }
2397
2398                         return null;
2399                 }
2400         }
2401 }