2 // enum.cs: Enum handling.
4 // Author: Miguel de Icaza (miguel@gnu.org)
5 // Ravi Pratap (ravi@ximian.com)
7 // Licensed under the terms of the GNU GPL
9 // (C) 2001 Ximian, Inc (http://www.ximian.com)
13 using System.Collections;
14 using System.Reflection;
15 using System.Reflection.Emit;
17 namespace Mono.CSharp {
20 /// Enumeration container
22 public class Enum : DeclSpace {
23 ArrayList ordered_enums;
25 public Expression BaseType;
27 public Type UnderlyingType;
29 Hashtable member_to_location;
30 Hashtable member_to_attributes;
33 // This is for members that have been defined
35 Hashtable member_to_value;
38 // This is used to mark members we're currently defining
42 ArrayList field_builders;
44 public const int AllowedModifiers =
51 public Enum (NamespaceEntry ns, TypeContainer parent, Expression type, int mod_flags,
52 string name, Attributes attrs, Location l)
53 : base (ns, parent, name, attrs, l)
56 ModFlags = Modifiers.Check (AllowedModifiers, mod_flags,
57 IsTopLevel ? Modifiers.INTERNAL : Modifiers.PRIVATE, l);
59 ordered_enums = new ArrayList ();
60 member_to_location = new Hashtable ();
61 member_to_value = new Hashtable ();
62 in_transit = new Hashtable ();
63 field_builders = new ArrayList ();
67 /// Adds @name to the enumeration space, with @expr
68 /// being its definition.
70 public AdditionResult AddEnumMember (string name, Expression expr, Location loc,
73 if (defined_names.Contains (name))
74 return AdditionResult.NameExists;
76 if (name == "value__") {
77 Report.Error (76, loc, "An item in an enumeration can't have an identifier `value__'");
78 return AdditionResult.Error;
81 DefineName (name, expr);
83 ordered_enums.Add (name);
84 member_to_location.Add (name, loc);
86 if (member_to_attributes == null)
87 member_to_attributes = new Hashtable ();
89 member_to_attributes.Add (name, opt_attrs);
91 return AdditionResult.Success;
95 // This is used by corlib compilation: we map from our
96 // type to a type that is consumable by the DefineField
98 Type MapToInternalType (Type t)
100 if (t == TypeManager.int32_type)
102 if (t == TypeManager.int64_type)
103 return typeof (long);
104 if (t == TypeManager.uint32_type)
105 return typeof (uint);
106 if (t == TypeManager.uint64_type)
107 return typeof (ulong);
108 if (t == TypeManager.float_type)
109 return typeof (float);
110 if (t == TypeManager.double_type)
111 return typeof (double);
112 if (t == TypeManager.byte_type)
113 return typeof (byte);
114 if (t == TypeManager.sbyte_type)
115 return typeof (sbyte);
116 if (t == TypeManager.char_type)
117 return typeof (char);
118 if (t == TypeManager.short_type)
119 return typeof (short);
120 if (t == TypeManager.ushort_type)
121 return typeof (ushort);
123 throw new Exception ();
126 public override TypeBuilder DefineType ()
128 if (TypeBuilder != null)
131 TypeAttributes attr = Modifiers.TypeAttr (ModFlags, IsTopLevel);
133 attr |= TypeAttributes.Class | TypeAttributes.Sealed;
135 UnderlyingType = ResolveType (BaseType, false, Location);
137 if (UnderlyingType != TypeManager.int32_type &&
138 UnderlyingType != TypeManager.uint32_type &&
139 UnderlyingType != TypeManager.int64_type &&
140 UnderlyingType != TypeManager.uint64_type &&
141 UnderlyingType != TypeManager.short_type &&
142 UnderlyingType != TypeManager.ushort_type &&
143 UnderlyingType != TypeManager.byte_type &&
144 UnderlyingType != TypeManager.char_type &&
145 UnderlyingType != TypeManager.sbyte_type) {
146 Report.Error (1008, Location,
147 "Type byte, sbyte, short, char, ushort, int, uint, " +
148 "long, or ulong expected (got: " +
149 TypeManager.CSharpName (UnderlyingType) + ")");
154 if (TypeManager.NamespaceClash (Name, Location))
157 ModuleBuilder builder = CodeGen.Module.Builder;
159 TypeBuilder = builder.DefineType (Name, attr, TypeManager.enum_type);
161 TypeBuilder builder = Parent.TypeBuilder;
163 TypeBuilder = builder.DefineNestedType (
164 Basename, attr, TypeManager.enum_type);
168 // Call MapToInternalType for corlib
170 TypeBuilder.DefineField ("value__", UnderlyingType,
171 FieldAttributes.Public | FieldAttributes.SpecialName
172 | FieldAttributes.RTSpecialName);
174 TypeManager.AddEnumType (Name, TypeBuilder, this);
179 bool IsValidEnumConstant (Expression e)
181 if (!(e is Constant))
184 if (e is IntConstant || e is UIntConstant || e is LongConstant ||
185 e is ByteConstant || e is SByteConstant || e is ShortConstant ||
186 e is UShortConstant || e is ULongConstant || e is EnumConstant ||
193 object GetNextDefaultValue (object default_value)
195 if (UnderlyingType == TypeManager.int32_type) {
196 int i = (int) default_value;
198 if (i < System.Int32.MaxValue)
202 } else if (UnderlyingType == TypeManager.uint32_type) {
203 uint i = (uint) default_value;
205 if (i < System.UInt32.MaxValue)
209 } else if (UnderlyingType == TypeManager.int64_type) {
210 long i = (long) default_value;
212 if (i < System.Int64.MaxValue)
216 } else if (UnderlyingType == TypeManager.uint64_type) {
217 ulong i = (ulong) default_value;
219 if (i < System.UInt64.MaxValue)
223 } else if (UnderlyingType == TypeManager.short_type) {
224 short i = (short) default_value;
226 if (i < System.Int16.MaxValue)
230 } else if (UnderlyingType == TypeManager.ushort_type) {
231 ushort i = (ushort) default_value;
233 if (i < System.UInt16.MaxValue)
237 } else if (UnderlyingType == TypeManager.byte_type) {
238 byte i = (byte) default_value;
240 if (i < System.Byte.MaxValue)
244 } else if (UnderlyingType == TypeManager.sbyte_type) {
245 sbyte i = (sbyte) default_value;
247 if (i < System.SByte.MaxValue)
256 void Error_ConstantValueCannotBeConverted (object val, Location loc)
259 Report.Error (31, loc, "Constant value '" + ((Constant) val).AsString () +
260 "' cannot be converted" +
261 " to a " + TypeManager.CSharpName (UnderlyingType));
263 Report.Error (31, loc, "Constant value '" + val +
264 "' cannot be converted" +
265 " to a " + TypeManager.CSharpName (UnderlyingType));
270 /// Determines if a standard implicit conversion exists from
271 /// expr_type to target_type
273 public static bool ImplicitConversionExists (Type expr_type, Type target_type)
275 expr_type = TypeManager.TypeToCoreType (expr_type);
277 if (expr_type == TypeManager.void_type)
280 if (expr_type == target_type)
283 // First numeric conversions
285 if (expr_type == TypeManager.sbyte_type){
287 // From sbyte to short, int, long, float, double.
289 if ((target_type == TypeManager.int32_type) ||
290 (target_type == TypeManager.int64_type) ||
291 (target_type == TypeManager.double_type) ||
292 (target_type == TypeManager.float_type) ||
293 (target_type == TypeManager.short_type) ||
294 (target_type == TypeManager.decimal_type))
297 } else if (expr_type == TypeManager.byte_type){
299 // From byte to short, ushort, int, uint, long, ulong, float, double
301 if ((target_type == TypeManager.short_type) ||
302 (target_type == TypeManager.ushort_type) ||
303 (target_type == TypeManager.int32_type) ||
304 (target_type == TypeManager.uint32_type) ||
305 (target_type == TypeManager.uint64_type) ||
306 (target_type == TypeManager.int64_type) ||
307 (target_type == TypeManager.float_type) ||
308 (target_type == TypeManager.double_type) ||
309 (target_type == TypeManager.decimal_type))
312 } else if (expr_type == TypeManager.short_type){
314 // From short to int, long, float, double
316 if ((target_type == TypeManager.int32_type) ||
317 (target_type == TypeManager.int64_type) ||
318 (target_type == TypeManager.double_type) ||
319 (target_type == TypeManager.float_type) ||
320 (target_type == TypeManager.decimal_type))
323 } else if (expr_type == TypeManager.ushort_type){
325 // From ushort to int, uint, long, ulong, float, double
327 if ((target_type == TypeManager.uint32_type) ||
328 (target_type == TypeManager.uint64_type) ||
329 (target_type == TypeManager.int32_type) ||
330 (target_type == TypeManager.int64_type) ||
331 (target_type == TypeManager.double_type) ||
332 (target_type == TypeManager.float_type) ||
333 (target_type == TypeManager.decimal_type))
336 } else if (expr_type == TypeManager.int32_type){
338 // From int to long, float, double
340 if ((target_type == TypeManager.int64_type) ||
341 (target_type == TypeManager.double_type) ||
342 (target_type == TypeManager.float_type) ||
343 (target_type == TypeManager.decimal_type))
346 } else if (expr_type == TypeManager.uint32_type){
348 // From uint to long, ulong, float, double
350 if ((target_type == TypeManager.int64_type) ||
351 (target_type == TypeManager.uint64_type) ||
352 (target_type == TypeManager.double_type) ||
353 (target_type == TypeManager.float_type) ||
354 (target_type == TypeManager.decimal_type))
357 } else if ((expr_type == TypeManager.uint64_type) ||
358 (expr_type == TypeManager.int64_type)) {
360 // From long/ulong to float, double
362 if ((target_type == TypeManager.double_type) ||
363 (target_type == TypeManager.float_type) ||
364 (target_type == TypeManager.decimal_type))
367 } else if (expr_type == TypeManager.char_type){
369 // From char to ushort, int, uint, long, ulong, float, double
371 if ((target_type == TypeManager.ushort_type) ||
372 (target_type == TypeManager.int32_type) ||
373 (target_type == TypeManager.uint32_type) ||
374 (target_type == TypeManager.uint64_type) ||
375 (target_type == TypeManager.int64_type) ||
376 (target_type == TypeManager.float_type) ||
377 (target_type == TypeManager.double_type) ||
378 (target_type == TypeManager.decimal_type))
381 } else if (expr_type == TypeManager.float_type){
385 if (target_type == TypeManager.double_type)
393 // Horrible, horrible. But there is no other way we can pass the EmitContext
394 // to the recursive definition triggered by the evaluation of a forward
397 static EmitContext current_ec = null;
400 /// This is used to lookup the value of an enum member. If the member is undefined,
401 /// it attempts to define it and return its value
403 public object LookupEnumValue (EmitContext ec, string name, Location loc)
406 object default_value = null;
409 default_value = member_to_value [name];
411 if (default_value != null)
412 return default_value;
415 // This may happen if we're calling a method in System.Enum, for instance
418 if (!defined_names.Contains (name))
421 if (in_transit.Contains (name)) {
422 Report.Error (110, loc, "The evaluation of the constant value for `" +
423 Name + "." + name + "' involves a circular definition.");
428 // So if the above doesn't happen, we have a member that is undefined
429 // We now proceed to define it
431 Expression val = this [name];
435 int idx = ordered_enums.IndexOf (name);
440 for (int i = 0; i < idx; ++i) {
441 string n = (string) ordered_enums [i];
442 Location m_loc = (Mono.CSharp.Location)
443 member_to_location [n];
444 in_transit.Add (name, true);
446 EmitContext old_ec = current_ec;
449 default_value = LookupEnumValue (ec, n, m_loc);
453 in_transit.Remove (name);
454 if (default_value == null)
458 default_value = GetNextDefaultValue (default_value);
462 bool old = ec.InEnumContext;
463 ec.InEnumContext = true;
464 in_transit.Add (name, true);
466 EmitContext old_ec = current_ec;
468 val = val.Resolve (ec);
471 in_transit.Remove (name);
472 ec.InEnumContext = old;
477 if (!IsValidEnumConstant (val)) {
480 "Type byte, sbyte, short, ushort, int, uint, long, or " +
481 "ulong expected (have: " + val + ")");
486 default_value = c.GetValue ();
488 if (default_value == null) {
489 Error_ConstantValueCannotBeConverted (c, loc);
493 if (val is EnumConstant){
494 Type etype = TypeManager.EnumToUnderlying (c.Type);
496 if (!ImplicitConversionExists (etype, UnderlyingType)){
497 Convert.Error_CannotImplicitConversion (
498 loc, c.Type, UnderlyingType);
504 FieldAttributes attr = FieldAttributes.Public | FieldAttributes.Static
505 | FieldAttributes.Literal;
507 FieldBuilder fb = TypeBuilder.DefineField (name, TypeBuilder, attr);
510 default_value = TypeManager.ChangeType (default_value, UnderlyingType, out fail);
512 Error_ConstantValueCannotBeConverted (c, loc);
516 fb.SetConstant (default_value);
517 field_builders.Add (fb);
518 member_to_value [name] = default_value;
520 if (!TypeManager.RegisterFieldValue (fb, default_value))
524 // Now apply attributes
526 Attribute.ApplyAttributes (ec, fb, fb, (Attributes) member_to_attributes [name]);
528 return default_value;
531 public override bool DefineMembers (TypeContainer parent)
536 public override bool Define (TypeContainer parent)
539 // If there was an error during DefineEnum, return
541 if (TypeBuilder == null)
544 EmitContext ec = new EmitContext (this, this, Location, null,
545 UnderlyingType, ModFlags, false);
548 object default_value = 0;
550 FieldAttributes attr = FieldAttributes.Public | FieldAttributes.Static
551 | FieldAttributes.Literal;
554 foreach (string name in ordered_enums) {
556 // Have we already been defined, thanks to some cross-referencing ?
558 if (member_to_value.Contains (name))
561 Location loc = (Mono.CSharp.Location) member_to_location [name];
563 if (this [name] != null) {
564 default_value = LookupEnumValue (ec, name, loc);
566 if (default_value == null)
569 if (name == "value__"){
570 Report.Error (76, loc, "The name `value__' is reserved for enumerations");
574 FieldBuilder fb = TypeBuilder.DefineField (
575 name, TypeBuilder, attr);
577 if (default_value == null) {
578 Report.Error (543, loc, "Enumerator value for '" + name + "' is too large to " +
584 default_value = TypeManager.ChangeType (default_value, UnderlyingType, out fail);
586 Error_ConstantValueCannotBeConverted (default_value, loc);
590 fb.SetConstant (default_value);
591 field_builders.Add (fb);
592 member_to_value [name] = default_value;
594 if (!TypeManager.RegisterFieldValue (fb, default_value))
598 // Apply attributes on the enum member
600 Attribute.ApplyAttributes (ec, fb, fb, (Attributes) member_to_attributes [name]);
603 default_value = GetNextDefaultValue (default_value);
606 Attribute.ApplyAttributes (ec, TypeBuilder, this, OptAttributes);
614 public override MemberList FindMembers (MemberTypes mt, BindingFlags bf,
615 MemberFilter filter, object criteria)
617 ArrayList members = new ArrayList ();
619 if ((mt & MemberTypes.Field) != 0) {
620 if (criteria is string){
621 if (member_to_value [criteria] == null && current_ec != null){
622 LookupEnumValue (current_ec, (string) criteria, Location.Null);
626 foreach (FieldBuilder fb in field_builders)
627 if (filter (fb, criteria) == true)
631 return new MemberList (members);
634 public override MemberCache MemberCache {
640 public ArrayList ValueNames {
642 return ordered_enums;
647 public Expression this [string name] {
649 return (Expression) defined_names [name];