mcs/mcs/enum.cs

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