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: Attributable {
  21                 string name;
  22                 Enum parent;
  23                 Location loc;
  24
  25                 static string[] attribute_targets = new string [] { "field" };
  26
  27                 public FieldBuilder builder;
  28
  29                 public EnumMember (string name, Enum parent, Location loc, Attributes attrs):
  30                         base (attrs)
  31                 {
  32                         this.name = name;
  33                         this.parent = parent;
  34                         this.loc = loc;
  35                 }
  36
  37                 public override void ApplyAttributeBuilder(Attribute a, CustomAttributeBuilder cb)
  38                 {
  39                         if (a.Type == TypeManager.marshal_as_attr_type) {
  40                                 UnmanagedMarshal marshal = a.GetMarshal ();
  41                                 if (marshal != null) {
  42                                         builder.SetMarshal (marshal);
  43                                         return;
  44                                 }
  45                                 Report.Warning_T (-24, a.Location);
  46                                 return;
  47                         }
  48
  49                         builder.SetCustomAttribute (cb);
  50                 }
  51
  52                 public override AttributeTargets AttributeTargets {
  53                         get {
  54                                 return AttributeTargets.Field;
  55                         }
  56                 }
  57
  58                 public override bool IsClsCompliaceRequired(DeclSpace ds)
  59                 {
  60                         return parent.IsClsCompliaceRequired (ds);
  61                 }
  62
  63                 public void DefineMember (TypeBuilder tb)
  64                 {
  65                         FieldAttributes attr = FieldAttributes.Public | FieldAttributes.Static
  66                                 | FieldAttributes.Literal;
  67
  68                         builder = tb.DefineField (name, tb, attr);
  69                 }
  70
  71                 public void Emit (EmitContext ec)
  72                 {
  73                         if (OptAttributes != null)
  74                                 OptAttributes.Emit (ec, this);
  75                 }
  76
  77                 protected override string[] ValidAttributeTargets {
  78                         get {
  79                                 return attribute_targets;
  80                         }
  81                 }
  82         }
  83
  84         /// <summary>
  85         ///   Enumeration container
  86         /// </summary>
  87         public class Enum : DeclSpace {
  88                 ArrayList ordered_enums;
  89
  90                 public Expression BaseType;
  91
  92                 public Type UnderlyingType;
  93
  94                 Hashtable member_to_location;
  95                 Hashtable member_to_attributes;
  96
  97                 //
  98                 // This is for members that have been defined
  99                 //
 100                 Hashtable member_to_value;
 101
 102                 //
 103                 // This is used to mark members we're currently defining
 104                 //
 105                 Hashtable in_transit;
 106
 107                 ArrayList field_builders;
 108
 109
 110                 Hashtable name_to_member;
 111
 112                 public const int AllowedModifiers =
 113                         Modifiers.NEW |
 114                         Modifiers.PUBLIC |
 115                         Modifiers.PROTECTED |
 116                         Modifiers.INTERNAL |
 117                         Modifiers.PRIVATE;
 118
 119                 public Enum (NamespaceEntry ns, TypeContainer parent, Expression type, int mod_flags,
 120                              string name, Attributes attrs, Location l)
 121                         : base (ns, parent, name, attrs, l)
 122                 {
 123                         this.BaseType = type;
 124                         ModFlags = Modifiers.Check (AllowedModifiers, mod_flags,
 125                                                     IsTopLevel ? Modifiers.INTERNAL : Modifiers.PRIVATE, l);
 126
 127                         ordered_enums = new ArrayList ();
 128                         member_to_location = new Hashtable ();
 129                         member_to_value = new Hashtable ();
 130                         in_transit = new Hashtable ();
 131                         field_builders = new ArrayList ();
 132
 133                         name_to_member = new Hashtable ();
 134                 }
 135
 136                 /// <summary>
 137                 ///   Adds @name to the enumeration space, with @expr
 138                 ///   being its definition.
 139                 /// </summary>
 140                 public AdditionResult AddEnumMember (string name, Expression expr, Location loc,
 141                                                      Attributes opt_attrs)
 142                 {
 143                         if (defined_names.Contains (name))
 144                                 return AdditionResult.NameExists;
 145
 146                         if (name == "value__") {
 147                                 Report.Error (76, loc, "An item in an enumeration can't have an identifier `value__'");
 148                                 return AdditionResult.Error;
 149                         }
 150
 151                         DefineName (name, expr);
 152
 153                         ordered_enums.Add (name);
 154                         member_to_location.Add (name, loc);
 155
 156                         if (member_to_attributes == null)
 157                                 member_to_attributes = new Hashtable ();
 158
 159                         member_to_attributes.Add (name, opt_attrs);
 160
 161                         name_to_member.Add (name, new EnumMember (name, this, loc, opt_attrs));
 162
 163                         return AdditionResult.Success;
 164                 }
 165
 166                 //
 167                 // This is used by corlib compilation: we map from our
 168                 // type to a type that is consumable by the DefineField
 169                 //
 170                 Type MapToInternalType (Type t)
 171                 {
 172                         if (t == TypeManager.int32_type)
 173                                 return typeof (int);
 174                         if (t == TypeManager.int64_type)
 175                                 return typeof (long);
 176                         if (t == TypeManager.uint32_type)
 177                                 return typeof (uint);
 178                         if (t == TypeManager.uint64_type)
 179                                 return typeof (ulong);
 180                         if (t == TypeManager.float_type)
 181                                 return typeof (float);
 182                         if (t == TypeManager.double_type)
 183                                 return typeof (double);
 184                         if (t == TypeManager.byte_type)
 185                                 return typeof (byte);
 186                         if (t == TypeManager.sbyte_type)
 187                                 return typeof (sbyte);
 188                         if (t == TypeManager.char_type)
 189                                 return typeof (char);
 190                         if (t == TypeManager.short_type)
 191                                 return typeof (short);
 192                         if (t == TypeManager.ushort_type)
 193                                 return typeof (ushort);
 194
 195                         throw new Exception ();
 196                 }
 197
 198                 public override TypeBuilder DefineType ()
 199                 {
 200                         if (TypeBuilder != null)
 201                                 return TypeBuilder;
 202
 203                         TypeAttributes attr = Modifiers.TypeAttr (ModFlags, IsTopLevel);
 204
 205                         attr |= TypeAttributes.Class | TypeAttributes.Sealed;
 206
 207                         if (!(BaseType is TypeLookupExpression)) {
 208                                 Report.Error (1008, Location,
 209                                               "Type byte, sbyte, short, ushort, int, uint, " +
 210                                               "long, or ulong expected (got: `{0}')", BaseType);
 211                                 return null;
 212                         }
 213
 214                         UnderlyingType = ResolveType (BaseType, false, Location);
 215
 216                         if (UnderlyingType != TypeManager.int32_type &&
 217                             UnderlyingType != TypeManager.uint32_type &&
 218                             UnderlyingType != TypeManager.int64_type &&
 219                             UnderlyingType != TypeManager.uint64_type &&
 220                             UnderlyingType != TypeManager.short_type &&
 221                             UnderlyingType != TypeManager.ushort_type &&
 222                             UnderlyingType != TypeManager.byte_type  &&
 223                             UnderlyingType != TypeManager.sbyte_type) {
 224                                 Report.Error (1008, Location,
 225                                               "Type byte, sbyte, short, ushort, int, uint, " +
 226                                               "long, or ulong expected (got: " +
 227                                               TypeManager.CSharpName (UnderlyingType) + ")");
 228                                 return null;
 229                         }
 230
 231                         if (IsTopLevel) {
 232                                 if (TypeManager.NamespaceClash (Name, Location))
 233                                         return null;
 234
 235                                 ModuleBuilder builder = CodeGen.Module.Builder;
 236
 237                                 TypeBuilder = builder.DefineType (Name, attr, TypeManager.enum_type);
 238                         } else {
 239                                 TypeBuilder builder = Parent.TypeBuilder;
 240
 241                                 TypeBuilder = builder.DefineNestedType (
 242                                         Basename, attr, TypeManager.enum_type);
 243                         }
 244
 245                         //
 246                         // Call MapToInternalType for corlib
 247                         //
 248                         TypeBuilder.DefineField ("value__", UnderlyingType,
 249                                                  FieldAttributes.Public | FieldAttributes.SpecialName
 250                                                  | FieldAttributes.RTSpecialName);
 251
 252                         TypeManager.AddEnumType (Name, TypeBuilder, this);
 253
 254                         return TypeBuilder;
 255                 }
 256
 257                 bool IsValidEnumConstant (Expression e)
 258                 {
 259                         if (!(e is Constant))
 260                                 return false;
 261
 262                         if (e is IntConstant || e is UIntConstant || e is LongConstant ||
 263                             e is ByteConstant || e is SByteConstant || e is ShortConstant ||
 264                             e is UShortConstant || e is ULongConstant || e is EnumConstant ||
 265                             e is CharConstant)
 266                                 return true;
 267                         else
 268                                 return false;
 269                 }
 270
 271                 object GetNextDefaultValue (object default_value)
 272                 {
 273                         if (UnderlyingType == TypeManager.int32_type) {
 274                                 int i = (int) default_value;
 275
 276                                 if (i < System.Int32.MaxValue)
 277                                         return ++i;
 278                                 else
 279                                         return null;
 280                         } else if (UnderlyingType == TypeManager.uint32_type) {
 281                                 uint i = (uint) default_value;
 282
 283                                 if (i < System.UInt32.MaxValue)
 284                                         return ++i;
 285                                 else
 286                                         return null;
 287                         } else if (UnderlyingType == TypeManager.int64_type) {
 288                                 long i = (long) default_value;
 289
 290                                 if (i < System.Int64.MaxValue)
 291                                         return ++i;
 292                                 else
 293                                         return null;
 294                         } else if (UnderlyingType == TypeManager.uint64_type) {
 295                                 ulong i = (ulong) default_value;
 296
 297                                 if (i < System.UInt64.MaxValue)
 298                                         return ++i;
 299                                 else
 300                                         return null;
 301                         } else if (UnderlyingType == TypeManager.short_type) {
 302                                 short i = (short) default_value;
 303
 304                                 if (i < System.Int16.MaxValue)
 305                                         return ++i;
 306                                 else
 307                                         return null;
 308                         } else if (UnderlyingType == TypeManager.ushort_type) {
 309                                 ushort i = (ushort) default_value;
 310
 311                                 if (i < System.UInt16.MaxValue)
 312                                         return ++i;
 313                                 else
 314                                         return null;
 315                         } else if (UnderlyingType == TypeManager.byte_type) {
 316                                 byte i = (byte) default_value;
 317
 318                                 if (i < System.Byte.MaxValue)
 319                                         return ++i;
 320                                 else
 321                                         return null;
 322                         } else if (UnderlyingType == TypeManager.sbyte_type) {
 323                                 sbyte i = (sbyte) default_value;
 324
 325                                 if (i < System.SByte.MaxValue)
 326                                         return ++i;
 327                                 else
 328                                         return null;
 329                         }
 330
 331                         return null;
 332                 }
 333
 334                 void Error_ConstantValueCannotBeConverted (object val, Location loc)
 335                 {
 336                         if (val is Constant)
 337                                 Report.Error (31, loc, "Constant value '" + ((Constant) val).AsString () +
 338                                               "' cannot be converted" +
 339                                               " to a " + TypeManager.CSharpName (UnderlyingType));
 340                         else
 341                                 Report.Error (31, loc, "Constant value '" + val +
 342                                               "' cannot be converted" +
 343                                               " to a " + TypeManager.CSharpName (UnderlyingType));
 344                         return;
 345                 }
 346
 347                 /// <summary>
 348                 ///  Determines if a standard implicit conversion exists from
 349                 ///  expr_type to target_type
 350                 /// </summary>
 351                 public static bool ImplicitConversionExists (Type expr_type, Type target_type)
 352                 {
 353                         expr_type = TypeManager.TypeToCoreType (expr_type);
 354
 355                         if (expr_type == TypeManager.void_type)
 356                                 return false;
 357
 358                         if (expr_type == target_type)
 359                                 return true;
 360
 361                         // First numeric conversions
 362
 363                         if (expr_type == TypeManager.sbyte_type){
 364                                 //
 365                                 // From sbyte to short, int, long, float, double.
 366                                 //
 367                                 if ((target_type == TypeManager.int32_type) ||
 368                                     (target_type == TypeManager.int64_type) ||
 369                                     (target_type == TypeManager.double_type) ||
 370                                     (target_type == TypeManager.float_type)  ||
 371                                     (target_type == TypeManager.short_type) ||
 372                                     (target_type == TypeManager.decimal_type))
 373                                         return true;
 374
 375                         } else if (expr_type == TypeManager.byte_type){
 376                                 //
 377                                 // From byte to short, ushort, int, uint, long, ulong, float, double
 378                                 //
 379                                 if ((target_type == TypeManager.short_type) ||
 380                                     (target_type == TypeManager.ushort_type) ||
 381                                     (target_type == TypeManager.int32_type) ||
 382                                     (target_type == TypeManager.uint32_type) ||
 383                                     (target_type == TypeManager.uint64_type) ||
 384                                     (target_type == TypeManager.int64_type) ||
 385                                     (target_type == TypeManager.float_type) ||
 386                                     (target_type == TypeManager.double_type) ||
 387                                     (target_type == TypeManager.decimal_type))
 388                                         return true;
 389
 390                         } else if (expr_type == TypeManager.short_type){
 391                                 //
 392                                 // From short to int, long, float, double
 393                                 //
 394                                 if ((target_type == TypeManager.int32_type) ||
 395                                     (target_type == TypeManager.int64_type) ||
 396                                     (target_type == TypeManager.double_type) ||
 397                                     (target_type == TypeManager.float_type) ||
 398                                     (target_type == TypeManager.decimal_type))
 399                                         return true;
 400
 401                         } else if (expr_type == TypeManager.ushort_type){
 402                                 //
 403                                 // From ushort to int, uint, long, ulong, float, double
 404                                 //
 405                                 if ((target_type == TypeManager.uint32_type) ||
 406                                     (target_type == TypeManager.uint64_type) ||
 407                                     (target_type == TypeManager.int32_type) ||
 408                                     (target_type == TypeManager.int64_type) ||
 409                                     (target_type == TypeManager.double_type) ||
 410                                     (target_type == TypeManager.float_type) ||
 411                                     (target_type == TypeManager.decimal_type))
 412                                         return true;
 413
 414                         } else if (expr_type == TypeManager.int32_type){
 415                                 //
 416                                 // From int to long, float, double
 417                                 //
 418                                 if ((target_type == TypeManager.int64_type) ||
 419                                     (target_type == TypeManager.double_type) ||
 420                                     (target_type == TypeManager.float_type) ||
 421                                     (target_type == TypeManager.decimal_type))
 422                                         return true;
 423
 424                         } else if (expr_type == TypeManager.uint32_type){
 425                                 //
 426                                 // From uint to long, ulong, float, double
 427                                 //
 428                                 if ((target_type == TypeManager.int64_type) ||
 429                                     (target_type == TypeManager.uint64_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.uint64_type) ||
 436                                    (expr_type == TypeManager.int64_type)) {
 437                                 //
 438                                 // From long/ulong to float, double
 439                                 //
 440                                 if ((target_type == TypeManager.double_type) ||
 441                                     (target_type == TypeManager.float_type) ||
 442                                     (target_type == TypeManager.decimal_type))
 443                                         return true;
 444
 445                         } else if (expr_type == TypeManager.char_type){
 446                                 //
 447                                 // From char to ushort, int, uint, long, ulong, float, double
 448                                 //
 449                                 if ((target_type == TypeManager.ushort_type) ||
 450                                     (target_type == TypeManager.int32_type) ||
 451                                     (target_type == TypeManager.uint32_type) ||
 452                                     (target_type == TypeManager.uint64_type) ||
 453                                     (target_type == TypeManager.int64_type) ||
 454                                     (target_type == TypeManager.float_type) ||
 455                                     (target_type == TypeManager.double_type) ||
 456                                     (target_type == TypeManager.decimal_type))
 457                                         return true;
 458
 459                         } else if (expr_type == TypeManager.float_type){
 460                                 //
 461                                 // float to double
 462                                 //
 463                                 if (target_type == TypeManager.double_type)
 464                                         return true;
 465                         }
 466
 467                         return false;
 468                 }
 469
 470                 //
 471                 // Horrible, horrible.  But there is no other way we can pass the EmitContext
 472                 // to the recursive definition triggered by the evaluation of a forward
 473                 // expression
 474                 //
 475                 static EmitContext current_ec = null;
 476
 477                 /// <summary>
 478                 ///  This is used to lookup the value of an enum member. If the member is undefined,
 479                 ///  it attempts to define it and return its value
 480                 /// </summary>
 481                 public object LookupEnumValue (EmitContext ec, string name, Location loc)
 482                 {
 483
 484                         object default_value = null;
 485                         Constant c = null;
 486
 487                         default_value = member_to_value [name];
 488
 489                         if (default_value != null)
 490                                 return default_value;
 491
 492                         //
 493                         // This may happen if we're calling a method in System.Enum, for instance
 494                         // Enum.IsDefined().
 495                         //
 496                         if (!defined_names.Contains (name))
 497                                 return null;
 498
 499                         if (in_transit.Contains (name)) {
 500                                 Report.Error (110, loc, "The evaluation of the constant value for `" +
 501                                               Name + "." + name + "' involves a circular definition.");
 502                                 return null;
 503                         }
 504
 505                         //
 506                         // So if the above doesn't happen, we have a member that is undefined
 507                         // We now proceed to define it
 508                         //
 509                         Expression val = this [name];
 510
 511                         if (val == null) {
 512
 513                                 int idx = ordered_enums.IndexOf (name);
 514
 515                                 if (idx == 0)
 516                                         default_value = 0;
 517                                 else {
 518                                         for (int i = 0; i < idx; ++i) {
 519                                                 string n = (string) ordered_enums [i];
 520                                                 Location m_loc = (Mono.CSharp.Location)
 521                                                         member_to_location [n];
 522                                                 in_transit.Add (name, true);
 523
 524                                                 EmitContext old_ec = current_ec;
 525                                                 current_ec = ec;
 526
 527                                                 default_value = LookupEnumValue (ec, n, m_loc);
 528
 529                                                 current_ec = old_ec;
 530
 531                                                 in_transit.Remove (name);
 532                                                 if (default_value == null)
 533                                                         return null;
 534                                         }
 535
 536                                         default_value = GetNextDefaultValue (default_value);
 537                                 }
 538
 539                         } else {
 540                                 bool old = ec.InEnumContext;
 541                                 ec.InEnumContext = true;
 542                                 in_transit.Add (name, true);
 543
 544                                 EmitContext old_ec = current_ec;
 545                                 current_ec = ec;
 546                                 val = val.Resolve (ec);
 547                                 current_ec = old_ec;
 548
 549                                 in_transit.Remove (name);
 550                                 ec.InEnumContext = old;
 551
 552                                 if (val == null)
 553                                         return null;
 554
 555                                 if (!IsValidEnumConstant (val)) {
 556                                         Report.Error (
 557                                                 1008, loc,
 558                                                 "Type byte, sbyte, short, ushort, int, uint, long, or " +
 559                                                 "ulong expected (have: " + val + ")");
 560                                         return null;
 561                                 }
 562
 563                                 c = (Constant) val;
 564                                 default_value = c.GetValue ();
 565
 566                                 if (default_value == null) {
 567                                         Error_ConstantValueCannotBeConverted (c, loc);
 568                                         return null;
 569                                 }
 570
 571                                 if (val is EnumConstant){
 572                                         Type etype = TypeManager.EnumToUnderlying (c.Type);
 573
 574                                         if (!ImplicitConversionExists (etype, UnderlyingType)){
 575                                                 Convert.Error_CannotImplicitConversion (
 576                                                         loc, c.Type, UnderlyingType);
 577                                                 return null;
 578                                         }
 579                                 }
 580                         }
 581
 582                         EnumMember em = name_to_member [name] as EnumMember;
 583                         em.DefineMember (TypeBuilder);
 584
 585                         bool fail;
 586                         default_value = TypeManager.ChangeType (default_value, UnderlyingType, out fail);
 587                         if (fail){
 588                                 Error_ConstantValueCannotBeConverted (c, loc);
 589                                 return null;
 590                         }
 591
 592                         em.builder.SetConstant (default_value);
 593                         field_builders.Add (em.builder);
 594                         member_to_value [name] = default_value;
 595
 596                         if (!TypeManager.RegisterFieldValue (em.builder, default_value))
 597                                 return null;
 598
 599                         return default_value;
 600                 }
 601
 602                 public override bool DefineMembers (TypeContainer parent)
 603                 {
 604                         return true;
 605                 }
 606
 607                 public override bool Define (TypeContainer parent)
 608                 {
 609                         //
 610                         // If there was an error during DefineEnum, return
 611                         //
 612                         if (TypeBuilder == null)
 613                                 return false;
 614
 615                         EmitContext ec = new EmitContext (this, this, Location, null,
 616                                                           UnderlyingType, ModFlags, false);
 617
 618
 619                         object default_value = 0;
 620
 621
 622                         foreach (string name in ordered_enums) {
 623                                 //
 624                                 // Have we already been defined, thanks to some cross-referencing ?
 625                                 //
 626                                 if (member_to_value.Contains (name))
 627                                         continue;
 628
 629                                 Location loc = (Mono.CSharp.Location) member_to_location [name];
 630
 631                                 if (this [name] != null) {
 632                                         default_value = LookupEnumValue (ec, name, loc);
 633
 634                                         if (default_value == null)
 635                                                 return true;
 636                                 } else {
 637                                         if (name == "value__"){
 638                                                 Report.Error (76, loc, "The name `value__' is reserved for enumerations");
 639                                                 return false;
 640                                         }
 641
 642                                         EnumMember em = name_to_member [name] as EnumMember;
 643
 644                                         em.DefineMember (TypeBuilder);
 645                                         FieldBuilder fb = em.builder;
 646
 647                                         if (default_value == null) {
 648                                            Report.Error (543, loc, "Enumerator value for '" + name + "' is too large to " +
 649                                                               "fit in its type");
 650                                                 return false;
 651                                         }
 652
 653                                         bool fail;
 654                                         default_value = TypeManager.ChangeType (default_value, UnderlyingType, out fail);
 655                                         if (fail){
 656                                                 Error_ConstantValueCannotBeConverted (default_value, loc);
 657                                                 return false;
 658                                         }
 659
 660                                         fb.SetConstant (default_value);
 661                                         field_builders.Add (fb);
 662                                         member_to_value [name] = default_value;
 663
 664                                         if (!TypeManager.RegisterFieldValue (fb, default_value))
 665                                                 return false;
 666                                 }
 667
 668                                 default_value = GetNextDefaultValue (default_value);
 669                         }
 670                         return true;
 671                 }
 672
 673                 public override void Emit (TypeContainer tc)
 674                 {
 675                         EmitContext ec = new EmitContext (tc, this, Location, null, null, ModFlags, false);
 676
 677                         if (OptAttributes != null) {
 678                                 OptAttributes.Emit (ec, this);
 679                         }
 680
 681                         foreach (EnumMember em in name_to_member.Values) {
 682                                 em.Emit (ec);
 683                         }
 684
 685                         base.Emit (tc);
 686                 }
 687
 688                 protected override bool IsIdentifierClsCompliant (DeclSpace ds)
 689                 {
 690                         if (!base.IsIdentifierClsCompliant (ds))
 691                                 return false;
 692
 693                         for (int i = 1; i < ordered_enums.Count; ++i) {
 694                                 string checked_name = ordered_enums [i] as string;
 695                                 for (int ii = 0; ii < ordered_enums.Count; ++ii) {
 696                                         if (ii == i)
 697                                                 continue;
 698
 699                                         string enumerator_name = ordered_enums [ii] as string;
 700                                         if (String.Compare (checked_name, enumerator_name, true, CultureInfo.InvariantCulture) == 0) {
 701                                                 Report.SymbolRelatedToPreviousError ((Location)member_to_location [enumerator_name], enumerator_name);
 702                                                 Report.Error_T (3005, (Location)member_to_location [checked_name], GetEnumeratorName (checked_name));
 703                                                 break;
 704                                         }
 705                                 }
 706                         }
 707                         return true;
 708                 }
 709
 710                 protected override bool VerifyClsCompliance (DeclSpace ds)
 711                 {
 712                         if (!base.VerifyClsCompliance (ds))
 713                                 return false;
 714
 715                         if (!AttributeTester.IsClsCompliant (UnderlyingType)) {
 716                                 Report.Error_T (3009, Location, GetSignatureForError (), TypeManager.CSharpName (UnderlyingType));
 717                         }
 718
 719                         return true;
 720                 }
 721
 722                 /// <summary>
 723                 /// Returns full enum name.
 724                 /// </summary>
 725                 string GetEnumeratorName (string valueName)
 726                 {
 727                         return String.Concat (Name, ".", valueName);
 728                 }
 729
 730                 //
 731                 // IMemberFinder
 732                 //
 733                 public override MemberList FindMembers (MemberTypes mt, BindingFlags bf,
 734                                                         MemberFilter filter, object criteria)
 735                 {
 736                         ArrayList members = new ArrayList ();
 737
 738                         if ((mt & MemberTypes.Field) != 0) {
 739                                 if (criteria is string){
 740                                         if (member_to_value [criteria] == null && current_ec != null){
 741                                                 LookupEnumValue (current_ec, (string) criteria, Location.Null);
 742                                         }
 743                                 }
 744
 745                                 foreach (FieldBuilder fb in field_builders)
 746                                         if (filter (fb, criteria) == true)
 747                                                 members.Add (fb);
 748                         }
 749
 750                         return new MemberList (members);
 751                 }
 752
 753                 public override MemberCache MemberCache {
 754                         get {
 755                                 return null;
 756                         }
 757                 }
 758
 759                 public ArrayList ValueNames {
 760                         get {
 761                                 return ordered_enums;
 762                         }
 763                 }
 764
 765                 // indexer
 766                 public Expression this [string name] {
 767                         get {
 768                                 return (Expression) defined_names [name];
 769                         }
 770                 }
 771
 772                 public override AttributeTargets AttributeTargets {
 773                         get {
 774                                 return AttributeTargets.Enum;
 775                         }
 776                 }
 777
 778         }
 779 }