2 // generic.cs: Generics support
4 // Authors: Martin Baulig (martin@ximian.com)
5 // Miguel de Icaza (miguel@ximian.com)
7 // Licensed under the terms of the GNU GPL
9 // (C) 2001, 2002, 2003 Ximian, Inc (http://www.ximian.com)
10 // (C) 2004 Novell, Inc
13 using System.Reflection;
14 using System.Reflection.Emit;
15 using System.Globalization;
16 using System.Collections;
18 using System.Text.RegularExpressions;
20 namespace Mono.CSharp {
23 /// Abstract base class for type parameter constraints.
24 /// The type parameter can come from a generic type definition or from reflection.
26 public abstract class GenericConstraints {
27 public abstract string TypeParameter {
31 public abstract GenericParameterAttributes Attributes {
35 public bool HasConstructorConstraint {
36 get { return (Attributes & GenericParameterAttributes.DefaultConstructorConstraint) != 0; }
39 public bool HasReferenceTypeConstraint {
40 get { return (Attributes & GenericParameterAttributes.ReferenceTypeConstraint) != 0; }
43 public bool HasValueTypeConstraint {
44 get { return (Attributes & GenericParameterAttributes.NotNullableValueTypeConstraint) != 0; }
47 public virtual bool HasClassConstraint {
48 get { return ClassConstraint != null; }
51 public abstract Type ClassConstraint {
55 public abstract Type[] InterfaceConstraints {
59 public abstract Type EffectiveBaseClass {
64 // Returns whether the type parameter is "known to be a reference type".
66 public virtual bool IsReferenceType {
68 if (HasReferenceTypeConstraint)
70 if (HasValueTypeConstraint)
73 if (ClassConstraint != null) {
74 if (ClassConstraint.IsValueType)
77 if (ClassConstraint != TypeManager.object_type)
81 foreach (Type t in InterfaceConstraints) {
82 if (!t.IsGenericParameter)
85 GenericConstraints gc = TypeManager.GetTypeParameterConstraints (t);
86 if ((gc != null) && gc.IsReferenceType)
95 // Returns whether the type parameter is "known to be a value type".
97 public virtual bool IsValueType {
99 if (HasValueTypeConstraint)
101 if (HasReferenceTypeConstraint)
104 if (ClassConstraint != null) {
105 if (!ClassConstraint.IsValueType)
108 if (ClassConstraint != TypeManager.value_type)
112 foreach (Type t in InterfaceConstraints) {
113 if (!t.IsGenericParameter)
116 GenericConstraints gc = TypeManager.GetTypeParameterConstraints (t);
117 if ((gc != null) && gc.IsValueType)
126 public enum SpecialConstraint
134 /// Tracks the constraints for a type parameter from a generic type definition.
136 public class Constraints : GenericConstraints {
138 ArrayList constraints;
142 // name is the identifier, constraints is an arraylist of
143 // Expressions (with types) or `true' for the constructor constraint.
145 public Constraints (string name, ArrayList constraints,
149 this.constraints = constraints;
153 public override string TypeParameter {
159 GenericParameterAttributes attrs;
160 TypeExpr class_constraint;
161 ArrayList iface_constraints;
162 ArrayList type_param_constraints;
164 Type class_constraint_type;
165 Type[] iface_constraint_types;
166 Type effective_base_type;
171 /// Resolve the constraints - but only resolve things into Expression's, not
172 /// into actual types.
174 public bool Resolve (EmitContext ec)
179 iface_constraints = new ArrayList ();
180 type_param_constraints = new ArrayList ();
182 foreach (object obj in constraints) {
183 if (HasConstructorConstraint) {
184 Report.Error (401, loc,
185 "The new() constraint must be last.");
189 if (obj is SpecialConstraint) {
190 SpecialConstraint sc = (SpecialConstraint) obj;
192 if (sc == SpecialConstraint.Constructor) {
193 if (!HasValueTypeConstraint) {
194 attrs |= GenericParameterAttributes.DefaultConstructorConstraint;
199 451, loc, "The new () constraint " +
200 "cannot be used with the `struct' " +
205 if ((num_constraints > 0) || HasReferenceTypeConstraint || HasValueTypeConstraint) {
206 Report.Error (449, loc,
207 "The `class' or `struct' " +
208 "constraint must be first");
212 if (sc == SpecialConstraint.ReferenceType)
213 attrs |= GenericParameterAttributes.ReferenceTypeConstraint;
215 attrs |= GenericParameterAttributes.NotNullableValueTypeConstraint;
219 int errors = Report.Errors;
220 FullNamedExpression fn = ((Expression) obj).ResolveAsTypeStep (ec);
223 if (errors != Report.Errors)
226 Report.Error (246, loc, "Cannot find type '{0}'", ((Expression) obj).GetSignatureForError ());
231 ConstructedType cexpr = fn as ConstructedType;
233 if (!cexpr.ResolveConstructedType (ec))
238 expr = fn.ResolveAsTypeTerminal (ec);
240 if ((expr == null) || (expr.Type == null))
243 TypeParameterExpr texpr = expr as TypeParameterExpr;
245 type_param_constraints.Add (expr);
246 else if (expr.IsInterface)
247 iface_constraints.Add (expr);
248 else if (class_constraint != null) {
249 Report.Error (406, loc,
250 "`{0}': the class constraint for `{1}' " +
251 "must come before any other constraints.",
254 } else if (HasReferenceTypeConstraint || HasValueTypeConstraint) {
255 Report.Error (450, loc, "`{0}': cannot specify both " +
256 "a constraint class and the `class' " +
257 "or `struct' constraint.", expr.Name);
260 class_constraint = expr;
265 ArrayList list = new ArrayList ();
266 foreach (TypeExpr iface_constraint in iface_constraints) {
267 foreach (Type type in list) {
268 if (!type.Equals (iface_constraint.Type))
271 Report.Error (405, loc,
272 "Duplicate constraint `{0}' for type " +
273 "parameter `{1}'.", iface_constraint.GetSignatureForError (),
278 list.Add (iface_constraint.Type);
281 foreach (TypeParameterExpr expr in type_param_constraints) {
282 foreach (Type type in list) {
283 if (!type.Equals (expr.Type))
286 Report.Error (405, loc,
287 "Duplicate constraint `{0}' for type " +
288 "parameter `{1}'.", expr.GetSignatureForError (), name);
292 list.Add (expr.Type);
295 iface_constraint_types = new Type [list.Count];
296 list.CopyTo (iface_constraint_types, 0);
298 if (class_constraint != null) {
299 class_constraint_type = class_constraint.Type;
300 if (class_constraint_type == null)
303 if (class_constraint_type.IsSealed) {
304 Report.Error (701, loc,
305 "`{0}' is not a valid bound. Bounds " +
306 "must be interfaces or non sealed " +
307 "classes", TypeManager.CSharpName (class_constraint_type));
311 if ((class_constraint_type == TypeManager.array_type) ||
312 (class_constraint_type == TypeManager.delegate_type) ||
313 (class_constraint_type == TypeManager.enum_type) ||
314 (class_constraint_type == TypeManager.value_type) ||
315 (class_constraint_type == TypeManager.object_type)) {
316 Report.Error (702, loc,
317 "Bound cannot be special class `{0}'",
318 TypeManager.CSharpName (class_constraint_type));
323 if (class_constraint_type != null)
324 effective_base_type = class_constraint_type;
325 else if (HasValueTypeConstraint)
326 effective_base_type = TypeManager.value_type;
328 effective_base_type = TypeManager.object_type;
334 bool CheckTypeParameterConstraints (TypeParameter tparam, Hashtable seen)
336 seen.Add (tparam, true);
338 Constraints constraints = tparam.Constraints;
339 if (constraints == null)
342 if (constraints.HasValueTypeConstraint) {
343 Report.Error (456, loc, "Type parameter `{0}' has " +
344 "the `struct' constraint, so it cannot " +
345 "be used as a constraint for `{1}'",
350 if (constraints.type_param_constraints == null)
353 foreach (TypeParameterExpr expr in constraints.type_param_constraints) {
354 if (seen.Contains (expr.TypeParameter)) {
355 Report.Error (454, loc, "Circular constraint " +
356 "dependency involving `{0}' and `{1}'",
357 tparam.Name, expr.Name);
361 if (!CheckTypeParameterConstraints (expr.TypeParameter, seen))
369 /// Resolve the constraints into actual types.
371 public bool ResolveTypes (EmitContext ec)
376 resolved_types = true;
378 foreach (object obj in constraints) {
379 ConstructedType cexpr = obj as ConstructedType;
383 if (!cexpr.CheckConstraints (ec))
387 foreach (TypeParameterExpr expr in type_param_constraints) {
388 Hashtable seen = new Hashtable ();
389 if (!CheckTypeParameterConstraints (expr.TypeParameter, seen))
393 foreach (TypeExpr iface_constraint in iface_constraints) {
394 if (iface_constraint.ResolveType (ec) == null)
398 if (class_constraint != null) {
399 if (class_constraint.ResolveType (ec) == null)
407 /// Check whether there are no conflicts in our type parameter constraints.
409 /// This is an example:
413 /// where U : T, struct
415 public bool CheckDependencies (EmitContext ec)
417 foreach (TypeParameterExpr expr in type_param_constraints) {
418 if (!CheckDependencies (expr.TypeParameter, ec))
425 bool CheckDependencies (TypeParameter tparam, EmitContext ec)
427 Constraints constraints = tparam.Constraints;
428 if (constraints == null)
431 if (HasValueTypeConstraint && constraints.HasClassConstraint) {
432 Report.Error (455, loc, "Type parameter `{0}' inherits " +
433 "conflicting constraints `{1}' and `{2}'",
434 name, TypeManager.CSharpName (constraints.ClassConstraint),
439 if (HasClassConstraint && constraints.HasClassConstraint) {
440 Type t1 = ClassConstraint;
441 TypeExpr e1 = class_constraint;
442 Type t2 = constraints.ClassConstraint;
443 TypeExpr e2 = constraints.class_constraint;
445 if (!Convert.ImplicitReferenceConversionExists (ec, e1, t2) &&
446 !Convert.ImplicitReferenceConversionExists (ec, e2, t1)) {
447 Report.Error (455, loc,
448 "Type parameter `{0}' inherits " +
449 "conflicting constraints `{1}' and `{2}'",
450 name, TypeManager.CSharpName (t1), TypeManager.CSharpName (t2));
455 if (constraints.type_param_constraints == null)
458 foreach (TypeParameterExpr expr in constraints.type_param_constraints) {
459 if (!CheckDependencies (expr.TypeParameter, ec))
466 public override GenericParameterAttributes Attributes {
467 get { return attrs; }
470 public override bool HasClassConstraint {
471 get { return class_constraint != null; }
474 public override Type ClassConstraint {
475 get { return class_constraint_type; }
478 public override Type[] InterfaceConstraints {
479 get { return iface_constraint_types; }
482 public override Type EffectiveBaseClass {
483 get { return effective_base_type; }
486 public bool IsSubclassOf (Type t)
488 if ((class_constraint_type != null) &&
489 class_constraint_type.IsSubclassOf (t))
492 if (iface_constraint_types == null)
495 foreach (Type iface in iface_constraint_types) {
496 if (TypeManager.IsSubclassOf (iface, t))
504 /// This is used when we're implementing a generic interface method.
505 /// Each method type parameter in implementing method must have the same
506 /// constraints than the corresponding type parameter in the interface
507 /// method. To do that, we're called on each of the implementing method's
510 public bool CheckInterfaceMethod (EmitContext ec, GenericConstraints gc)
512 if (gc.Attributes != attrs)
515 if (HasClassConstraint != gc.HasClassConstraint)
517 if (HasClassConstraint && !TypeManager.IsEqual (gc.ClassConstraint, ClassConstraint))
520 int gc_icount = gc.InterfaceConstraints != null ?
521 gc.InterfaceConstraints.Length : 0;
522 int icount = InterfaceConstraints != null ?
523 InterfaceConstraints.Length : 0;
525 if (gc_icount != icount)
528 foreach (Type iface in gc.InterfaceConstraints) {
530 foreach (Type check in InterfaceConstraints) {
531 if (TypeManager.IsEqual (iface, check)) {
546 /// A type parameter from a generic type definition.
548 public class TypeParameter : MemberCore, IMemberContainer {
551 GenericConstraints gc;
552 Constraints constraints;
554 GenericTypeParameterBuilder type;
556 public TypeParameter (TypeContainer parent, DeclSpace decl, string name,
557 Constraints constraints, Attributes attrs, Location loc)
558 : base (parent, new MemberName (name, loc), attrs)
562 this.constraints = constraints;
566 public GenericConstraints GenericConstraints {
568 return gc != null ? gc : constraints;
572 public Constraints Constraints {
578 public bool HasConstructorConstraint {
580 if (constraints != null)
581 return constraints.HasConstructorConstraint;
587 public DeclSpace DeclSpace {
600 /// This is the first method which is called during the resolving
601 /// process; we're called immediately after creating the type parameters
602 /// with SRE (by calling `DefineGenericParameters()' on the TypeBuilder /
605 /// We're either called from TypeContainer.DefineType() or from
606 /// GenericMethod.Define() (called from Method.Define()).
608 public void Define (GenericTypeParameterBuilder type)
610 if (this.type != null)
611 throw new InvalidOperationException ();
614 TypeManager.AddTypeParameter (type, this);
618 /// This is the second method which is called during the resolving
619 /// process - in case of class type parameters, we're called from
620 /// TypeContainer.ResolveType() - after it resolved the class'es
621 /// base class and interfaces. For method type parameters, we're
622 /// called immediately after Define().
624 /// We're just resolving the constraints into expressions here, we
625 /// don't resolve them into actual types.
627 /// Note that in the special case of partial generic classes, we may be
628 /// called _before_ Define() and we may also be called multiple types.
630 public bool Resolve (DeclSpace ds)
632 if (constraints != null) {
633 if (!constraints.Resolve (ds.EmitContext)) {
643 /// This is the third method which is called during the resolving
644 /// process. We're called immediately after calling DefineConstraints()
645 /// on all of the current class'es type parameters.
647 /// Our job is to resolve the constraints to actual types.
649 /// Note that we may have circular dependencies on type parameters - this
650 /// is why Resolve() and ResolveType() are separate.
652 public bool ResolveType (EmitContext ec)
654 if (constraints != null) {
655 if (!constraints.ResolveTypes (ec)) {
665 /// This is the fourth and last method which is called during the resolving
666 /// process. We're called after everything is fully resolved and actually
667 /// register the constraints with SRE and the TypeManager.
669 public bool DefineType (EmitContext ec)
671 return DefineType (ec, null, null, false);
675 /// This is the fith and last method which is called during the resolving
676 /// process. We're called after everything is fully resolved and actually
677 /// register the constraints with SRE and the TypeManager.
679 /// The `builder', `implementing' and `is_override' arguments are only
680 /// applicable to method type parameters.
682 public bool DefineType (EmitContext ec, MethodBuilder builder,
683 MethodInfo implementing, bool is_override)
685 if (!ResolveType (ec))
688 if (implementing != null) {
689 if (is_override && (constraints != null)) {
691 460, loc, "Constraints for override and " +
692 "explicit interface implementation methods " +
693 "are inherited from the base method so they " +
694 "cannot be specified directly");
698 MethodBase mb = implementing;
699 if (mb.Mono_IsInflatedMethod)
700 mb = mb.GetGenericMethodDefinition ();
702 int pos = type.GenericParameterPosition;
703 Type mparam = mb.GetGenericArguments () [pos];
704 GenericConstraints temp_gc = ReflectionConstraints.GetConstraints (mparam);
707 gc = new InflatedConstraints (temp_gc, implementing.DeclaringType);
708 else if (constraints != null)
709 gc = new InflatedConstraints (constraints, implementing.DeclaringType);
712 if (constraints != null) {
715 else if (!constraints.CheckInterfaceMethod (ec, gc))
718 if (!is_override && (temp_gc != null))
723 Report.SymbolRelatedToPreviousError (implementing);
726 425, loc, "The constraints for type " +
727 "parameter `{0}' of method `{1}' must match " +
728 "the constraints for type parameter `{2}' " +
729 "of interface method `{3}'. Consider using " +
730 "an explicit interface implementation instead",
731 Name, TypeManager.CSharpSignature (builder),
732 TypeManager.CSharpName (mparam), TypeManager.CSharpSignature (mb));
735 } else if (DeclSpace is Iterator) {
736 TypeParameter[] tparams = DeclSpace.TypeParameters;
737 Type[] types = new Type [tparams.Length];
738 for (int i = 0; i < tparams.Length; i++)
739 types [i] = tparams [i].Type;
741 if (constraints != null)
742 gc = new InflatedConstraints (constraints, types);
744 gc = (GenericConstraints) constraints;
750 if (gc.HasClassConstraint)
751 type.SetBaseTypeConstraint (gc.ClassConstraint);
753 type.SetInterfaceConstraints (gc.InterfaceConstraints);
754 type.SetGenericParameterAttributes (gc.Attributes);
755 TypeManager.RegisterBuilder (type, gc.InterfaceConstraints);
761 /// Check whether there are no conflicts in our type parameter constraints.
763 /// This is an example:
767 /// where U : T, struct
769 public bool CheckDependencies (EmitContext ec)
771 if (constraints != null)
772 return constraints.CheckDependencies (ec);
778 /// This is called for each part of a partial generic type definition.
780 /// If `new_constraints' is not null and we don't already have constraints,
781 /// they become our constraints. If we already have constraints, we must
782 /// check that they're the same.
785 public bool UpdateConstraints (EmitContext ec, Constraints new_constraints)
788 throw new InvalidOperationException ();
790 if (constraints == null) {
791 new_constraints = constraints;
793 } else if (new_constraints == null)
796 if (!new_constraints.Resolve (ec))
798 if (!new_constraints.ResolveTypes (ec))
801 return constraints.CheckInterfaceMethod (ec, new_constraints);
804 public void EmitAttributes (EmitContext ec)
806 if (OptAttributes != null)
807 OptAttributes.Emit (ec, this);
810 public override string DocCommentHeader {
812 throw new InvalidOperationException (
813 "Unexpected attempt to get doc comment from " + this.GetType () + ".");
821 public override bool Define ()
826 public override void ApplyAttributeBuilder (Attribute a,
827 CustomAttributeBuilder cb)
829 type.SetCustomAttribute (cb);
832 public override AttributeTargets AttributeTargets {
834 return (AttributeTargets) AttributeTargets.GenericParameter;
838 public override string[] ValidAttributeTargets {
840 return new string [] { "type parameter" };
848 string IMemberContainer.Name {
852 MemberCache IMemberContainer.BaseCache {
856 bool IMemberContainer.IsInterface {
860 MemberList IMemberContainer.GetMembers (MemberTypes mt, BindingFlags bf)
862 return FindMembers (mt, bf, null, null);
865 MemberCache IMemberContainer.MemberCache {
869 public MemberList FindMembers (MemberTypes mt, BindingFlags bf,
870 MemberFilter filter, object criteria)
872 if (constraints == null)
873 return MemberList.Empty;
875 ArrayList members = new ArrayList ();
877 GenericConstraints gc = (GenericConstraints) constraints;
879 if (gc.HasClassConstraint) {
880 MemberList list = TypeManager.FindMembers (
881 gc.ClassConstraint, mt, bf, filter, criteria);
883 members.AddRange (list);
886 Type[] ifaces = TypeManager.ExpandInterfaces (gc.InterfaceConstraints);
887 foreach (Type t in ifaces) {
888 MemberList list = TypeManager.FindMembers (
889 t, mt, bf, filter, criteria);
891 members.AddRange (list);
894 return new MemberList (members);
897 public bool IsSubclassOf (Type t)
902 if (constraints != null)
903 return constraints.IsSubclassOf (t);
908 public override string ToString ()
910 return "TypeParameter[" + name + "]";
913 public static string GetSignatureForError (TypeParameter[] tp)
915 if (tp == null || tp.Length == 0)
918 StringBuilder sb = new StringBuilder ("<");
919 for (int i = 0; i < tp.Length; ++i) {
922 sb.Append (tp[i].GetSignatureForError ());
925 return sb.ToString ();
928 protected class InflatedConstraints : GenericConstraints
930 GenericConstraints gc;
932 Type class_constraint;
933 Type[] iface_constraints;
936 public InflatedConstraints (GenericConstraints gc, Type declaring)
937 : this (gc, TypeManager.GetTypeArguments (declaring))
940 public InflatedConstraints (GenericConstraints gc, Type[] dargs)
945 ArrayList list = new ArrayList ();
946 if (gc.HasClassConstraint)
947 list.Add (inflate (gc.ClassConstraint));
948 foreach (Type iface in gc.InterfaceConstraints)
949 list.Add (inflate (iface));
951 bool has_class_constr = false;
952 if (list.Count > 0) {
953 Type first = (Type) list [0];
954 has_class_constr = !first.IsInterface && !first.IsGenericParameter;
957 if ((list.Count > 0) && has_class_constr) {
958 class_constraint = (Type) list [0];
959 iface_constraints = new Type [list.Count - 1];
960 list.CopyTo (1, iface_constraints, 0, list.Count - 1);
962 iface_constraints = new Type [list.Count];
963 list.CopyTo (iface_constraints, 0);
966 if (HasValueTypeConstraint)
967 base_type = TypeManager.value_type;
968 else if (class_constraint != null)
969 base_type = class_constraint;
971 base_type = TypeManager.object_type;
974 Type inflate (Type t)
978 if (t.IsGenericParameter)
979 return dargs [t.GenericParameterPosition];
980 if (t.IsGenericInstance) {
981 t = t.GetGenericTypeDefinition ();
982 t = t.MakeGenericType (dargs);
988 public override string TypeParameter {
989 get { return gc.TypeParameter; }
992 public override GenericParameterAttributes Attributes {
993 get { return gc.Attributes; }
996 public override Type ClassConstraint {
997 get { return class_constraint; }
1000 public override Type EffectiveBaseClass {
1001 get { return base_type; }
1004 public override Type[] InterfaceConstraints {
1005 get { return iface_constraints; }
1011 /// A TypeExpr which already resolved to a type parameter.
1013 public class TypeParameterExpr : TypeExpr {
1014 TypeParameter type_parameter;
1016 public override string Name {
1018 return type_parameter.Name;
1022 public override string FullName {
1024 return type_parameter.Name;
1028 public TypeParameter TypeParameter {
1030 return type_parameter;
1034 public TypeParameterExpr (TypeParameter type_parameter, Location loc)
1036 this.type_parameter = type_parameter;
1040 protected override TypeExpr DoResolveAsTypeStep (EmitContext ec)
1042 type = type_parameter.Type;
1047 public override bool IsInterface {
1048 get { return false; }
1051 public override bool CheckAccessLevel (DeclSpace ds)
1056 public void Error_CannotUseAsUnmanagedType (Location loc)
1058 Report.Error (-203, loc, "Can not use type parameter as unamanged type");
1063 /// Tracks the type arguments when instantiating a generic type. We're used in
1064 /// ConstructedType.
1066 public class TypeArguments {
1067 public readonly Location Location;
1074 public TypeArguments (Location loc)
1076 args = new ArrayList ();
1077 this.Location = loc;
1080 public TypeArguments (int dimension, Location loc)
1082 this.dimension = dimension;
1083 this.Location = loc;
1086 public void Add (Expression type)
1089 throw new InvalidOperationException ();
1094 public void Add (TypeArguments new_args)
1097 throw new InvalidOperationException ();
1099 args.AddRange (new_args.args);
1103 /// We're used during the parsing process: the parser can't distinguish
1104 /// between type parameters and type arguments. Because of that, the
1105 /// parser creates a `MemberName' with `TypeArguments' for both cases and
1106 /// in case of a generic type definition, we call GetDeclarations().
1108 public TypeParameterName[] GetDeclarations ()
1110 TypeParameterName[] ret = new TypeParameterName [args.Count];
1111 for (int i = 0; i < args.Count; i++) {
1112 TypeParameterName name = args [i] as TypeParameterName;
1117 SimpleName sn = args [i] as SimpleName;
1119 ret [i] = new TypeParameterName (sn.Name, null, sn.Location);
1123 Report.Error (81, Location, "Type parameter declaration " +
1124 "must be an identifier not a type");
1131 /// We may only be used after Resolve() is called and return the fully
1134 public Type[] Arguments {
1140 public bool HasTypeArguments {
1142 return has_type_args;
1155 public bool IsUnbound {
1157 return dimension > 0;
1161 public override string ToString ()
1163 StringBuilder s = new StringBuilder ();
1166 for (int i = 0; i < count; i++){
1168 // FIXME: Use TypeManager.CSharpname once we have the type
1171 s.Append (args [i].ToString ());
1175 return s.ToString ();
1179 /// Resolve the type arguments.
1181 public bool Resolve (EmitContext ec)
1183 int count = args.Count;
1186 atypes = new Type [count];
1188 for (int i = 0; i < count; i++){
1189 TypeExpr te = ((Expression) args [i]).ResolveAsTypeTerminal (ec);
1194 if (te is TypeParameterExpr)
1195 has_type_args = true;
1197 if (te.Type.IsPointer) {
1198 Report.Error (306, Location, "The type `{0}' may not be used " +
1199 "as a type argument.", TypeManager.CSharpName (te.Type));
1201 } else if (te.Type == TypeManager.void_type) {
1202 Report.Error (1547, Location,
1203 "Keyword `void' cannot be used in this context");
1207 atypes [i] = te.Type;
1213 public class TypeParameterName : SimpleName
1215 Attributes attributes;
1217 public TypeParameterName (string name, Attributes attrs, Location loc)
1223 public Attributes OptAttributes {
1231 /// An instantiation of a generic type.
1233 public class ConstructedType : TypeExpr {
1235 FullNamedExpression name;
1237 Type[] gen_params, atypes;
1241 /// Instantiate the generic type `fname' with the type arguments `args'.
1243 public ConstructedType (FullNamedExpression fname, TypeArguments args, Location l)
1249 eclass = ExprClass.Type;
1250 full_name = name + "<" + args.ToString () + ">";
1253 protected ConstructedType (TypeArguments args, Location l)
1258 eclass = ExprClass.Type;
1261 protected ConstructedType (TypeParameter[] type_params, Location l)
1265 args = new TypeArguments (l);
1266 foreach (TypeParameter type_param in type_params)
1267 args.Add (new TypeParameterExpr (type_param, l));
1269 eclass = ExprClass.Type;
1273 /// This is used to construct the `this' type inside a generic type definition.
1275 public ConstructedType (Type t, TypeParameter[] type_params, Location l)
1276 : this (type_params, l)
1278 gt = t.GetGenericTypeDefinition ();
1280 this.name = new TypeExpression (gt, l);
1281 full_name = gt.FullName + "<" + args.ToString () + ">";
1285 /// Instantiate the generic type `t' with the type arguments `args'.
1286 /// Use this constructor if you already know the fully resolved
1289 public ConstructedType (Type t, TypeArguments args, Location l)
1292 gt = t.GetGenericTypeDefinition ();
1294 this.name = new TypeExpression (gt, l);
1295 full_name = gt.FullName + "<" + args.ToString () + ">";
1298 public TypeArguments TypeArguments {
1299 get { return args; }
1302 public override string GetSignatureForError ()
1304 return TypeManager.CSharpName (gt);
1307 protected override TypeExpr DoResolveAsTypeStep (EmitContext ec)
1309 if (!ResolveConstructedType (ec))
1316 /// Check the constraints; we're called from ResolveAsTypeTerminal()
1317 /// after fully resolving the constructed type.
1319 public bool CheckConstraints (EmitContext ec)
1321 return ConstraintChecker.CheckConstraints (ec, gt, gen_params, atypes, loc);
1325 /// Resolve the constructed type, but don't check the constraints.
1327 public bool ResolveConstructedType (EmitContext ec)
1331 // If we already know the fully resolved generic type.
1333 return DoResolveType (ec);
1339 Report.Error (246, loc, "Cannot find type `{0}'<...>", Name);
1343 num_args = TypeManager.GetNumberOfTypeArguments (t);
1344 if (num_args == 0) {
1345 Report.Error (308, loc,
1346 "The non-generic type `{0}' cannot " +
1347 "be used with type arguments.",
1348 TypeManager.CSharpName (t));
1352 gt = t.GetGenericTypeDefinition ();
1353 return DoResolveType (ec);
1356 bool DoResolveType (EmitContext ec)
1359 // Resolve the arguments.
1361 if (args.Resolve (ec) == false)
1364 gen_params = gt.GetGenericArguments ();
1365 atypes = args.Arguments;
1367 if (atypes.Length != gen_params.Length) {
1368 Report.Error (305, loc,
1369 "Using the generic type `{0}' " +
1370 "requires {1} type arguments",
1371 TypeManager.CSharpName (gt),
1372 gen_params.Length.ToString ());
1377 // Now bind the parameters.
1379 type = gt.MakeGenericType (atypes);
1383 public Expression GetSimpleName (EmitContext ec)
1388 public override bool CheckAccessLevel (DeclSpace ds)
1390 return ds.CheckAccessLevel (gt);
1393 public override bool AsAccessible (DeclSpace ds, int flags)
1395 return ds.AsAccessible (gt, flags);
1398 public override bool IsClass {
1399 get { return gt.IsClass; }
1402 public override bool IsValueType {
1403 get { return gt.IsValueType; }
1406 public override bool IsInterface {
1407 get { return gt.IsInterface; }
1410 public override bool IsSealed {
1411 get { return gt.IsSealed; }
1414 public override bool Equals (object obj)
1416 ConstructedType cobj = obj as ConstructedType;
1420 if ((type == null) || (cobj.type == null))
1423 return type == cobj.type;
1426 public override int GetHashCode ()
1428 return base.GetHashCode ();
1431 public override string Name {
1438 public override string FullName {
1445 public abstract class ConstraintChecker
1447 protected readonly Type[] gen_params;
1448 protected readonly Type[] atypes;
1449 protected readonly Location loc;
1451 protected ConstraintChecker (Type[] gen_params, Type[] atypes, Location loc)
1453 this.gen_params = gen_params;
1454 this.atypes = atypes;
1459 /// Check the constraints; we're called from ResolveAsTypeTerminal()
1460 /// after fully resolving the constructed type.
1462 public bool CheckConstraints (EmitContext ec)
1464 for (int i = 0; i < gen_params.Length; i++) {
1465 if (!CheckConstraints (ec, i))
1472 protected bool CheckConstraints (EmitContext ec, int index)
1474 Type atype = atypes [index];
1475 Type ptype = gen_params [index];
1480 Expression aexpr = new EmptyExpression (atype);
1482 GenericConstraints gc = TypeManager.GetTypeParameterConstraints (ptype);
1486 bool is_class, is_struct;
1487 if (atype.IsGenericParameter) {
1488 GenericConstraints agc = TypeManager.GetTypeParameterConstraints (atype);
1490 is_class = agc.HasReferenceTypeConstraint;
1491 is_struct = agc.HasValueTypeConstraint;
1493 is_class = is_struct = false;
1496 is_class = atype.IsClass;
1497 is_struct = atype.IsValueType;
1501 // First, check the `class' and `struct' constraints.
1503 if (gc.HasReferenceTypeConstraint && !is_class) {
1504 Report.Error (452, loc, "The type `{0}' must be " +
1505 "a reference type in order to use it " +
1506 "as type parameter `{1}' in the " +
1507 "generic type or method `{2}'.",
1508 TypeManager.CSharpName (atype),
1509 TypeManager.CSharpName (ptype),
1510 GetSignatureForError ());
1512 } else if (gc.HasValueTypeConstraint && !is_struct) {
1513 Report.Error (453, loc, "The type `{0}' must be " +
1514 "a value type in order to use it " +
1515 "as type parameter `{1}' in the " +
1516 "generic type or method `{2}'.",
1517 TypeManager.CSharpName (atype),
1518 TypeManager.CSharpName (ptype),
1519 GetSignatureForError ());
1524 // The class constraint comes next.
1526 if (gc.HasClassConstraint) {
1527 if (!CheckConstraint (ec, ptype, aexpr, gc.ClassConstraint)) {
1528 Error_TypeMustBeConvertible (atype, gc.ClassConstraint, ptype);
1534 // Now, check the interface constraints.
1536 foreach (Type it in gc.InterfaceConstraints) {
1538 if (it.IsGenericParameter)
1539 itype = atypes [it.GenericParameterPosition];
1543 if (!CheckConstraint (ec, ptype, aexpr, itype)) {
1544 Error_TypeMustBeConvertible (atype, itype, ptype);
1550 // Finally, check the constructor constraint.
1553 if (!gc.HasConstructorConstraint)
1556 if (TypeManager.IsBuiltinType (atype) || atype.IsValueType)
1559 if (HasDefaultConstructor (ec, atype))
1562 Report_SymbolRelatedToPreviousError ();
1563 Report.SymbolRelatedToPreviousError (atype);
1564 Report.Error (310, loc, "The type `{0}' must have a public " +
1565 "parameterless constructor in order to use it " +
1566 "as parameter `{1}' in the generic type or " +
1568 TypeManager.CSharpName (atype),
1569 TypeManager.CSharpName (ptype),
1570 GetSignatureForError ());
1574 protected bool CheckConstraint (EmitContext ec, Type ptype, Expression expr,
1577 if (TypeManager.HasGenericArguments (ctype)) {
1578 Type[] types = TypeManager.GetTypeArguments (ctype);
1580 TypeArguments new_args = new TypeArguments (loc);
1582 for (int i = 0; i < types.Length; i++) {
1585 if (t.IsGenericParameter) {
1586 int pos = t.GenericParameterPosition;
1589 new_args.Add (new TypeExpression (t, loc));
1592 TypeExpr ct = new ConstructedType (ctype, new_args, loc);
1593 if (ct.ResolveAsTypeStep (ec) == null)
1598 return Convert.ImplicitStandardConversionExists (ec, expr, ctype);
1601 bool HasDefaultConstructor (EmitContext ec, Type atype)
1603 if (atype is TypeBuilder) {
1604 if (atype.IsAbstract)
1607 TypeContainer tc = TypeManager.LookupTypeContainer (atype);
1608 foreach (Constructor c in tc.InstanceConstructors) {
1609 if ((c.ModFlags & Modifiers.PUBLIC) == 0)
1611 if ((c.Parameters.FixedParameters != null) &&
1612 (c.Parameters.FixedParameters.Length != 0))
1614 if (c.Parameters.HasArglist || c.Parameters.HasParams)
1621 MethodGroupExpr mg = Expression.MemberLookup (
1622 ec, atype, ".ctor", MemberTypes.Constructor,
1623 BindingFlags.Public | BindingFlags.Instance |
1624 BindingFlags.DeclaredOnly, loc)
1627 if (!atype.IsAbstract && (mg != null) && mg.IsInstance) {
1628 foreach (MethodBase mb in mg.Methods) {
1629 ParameterData pd = TypeManager.GetParameterData (mb);
1638 protected abstract string GetSignatureForError ();
1639 protected abstract void Report_SymbolRelatedToPreviousError ();
1641 void Error_TypeMustBeConvertible (Type atype, Type gc, Type ptype)
1643 Report_SymbolRelatedToPreviousError ();
1644 Report.SymbolRelatedToPreviousError (atype);
1645 Report.Error (309, loc,
1646 "The type `{0}' must be convertible to `{1}' in order to " +
1647 "use it as parameter `{2}' in the generic type or method `{3}'",
1648 TypeManager.CSharpName (atype), TypeManager.CSharpName (gc),
1649 TypeManager.CSharpName (ptype), GetSignatureForError ());
1652 public static bool CheckConstraints (EmitContext ec, MethodBase definition,
1653 MethodBase instantiated, Location loc)
1655 MethodConstraintChecker checker = new MethodConstraintChecker (
1656 definition, definition.GetGenericArguments (),
1657 instantiated.GetGenericArguments (), loc);
1659 return checker.CheckConstraints (ec);
1662 public static bool CheckConstraints (EmitContext ec, Type gt, Type[] gen_params,
1663 Type[] atypes, Location loc)
1665 TypeConstraintChecker checker = new TypeConstraintChecker (
1666 gt, gen_params, atypes, loc);
1668 return checker.CheckConstraints (ec);
1671 protected class MethodConstraintChecker : ConstraintChecker
1673 MethodBase definition;
1675 public MethodConstraintChecker (MethodBase definition, Type[] gen_params,
1676 Type[] atypes, Location loc)
1677 : base (gen_params, atypes, loc)
1679 this.definition = definition;
1682 protected override string GetSignatureForError ()
1684 return TypeManager.CSharpSignature (definition);
1687 protected override void Report_SymbolRelatedToPreviousError ()
1689 Report.SymbolRelatedToPreviousError (definition);
1693 protected class TypeConstraintChecker : ConstraintChecker
1697 public TypeConstraintChecker (Type gt, Type[] gen_params, Type[] atypes,
1699 : base (gen_params, atypes, loc)
1704 protected override string GetSignatureForError ()
1706 return TypeManager.CSharpName (gt);
1709 protected override void Report_SymbolRelatedToPreviousError ()
1711 Report.SymbolRelatedToPreviousError (gt);
1717 /// A generic method definition.
1719 public class GenericMethod : DeclSpace
1721 Expression return_type;
1722 Parameters parameters;
1724 public GenericMethod (NamespaceEntry ns, TypeContainer parent, MemberName name,
1725 Expression return_type, Parameters parameters)
1726 : base (ns, parent, name, null)
1728 this.return_type = return_type;
1729 this.parameters = parameters;
1732 public override TypeBuilder DefineType ()
1734 throw new Exception ();
1737 public override bool Define ()
1739 ec = new EmitContext (this, this, Location, null, null, ModFlags, false);
1741 for (int i = 0; i < TypeParameters.Length; i++)
1742 if (!TypeParameters [i].Resolve (this))
1749 /// Define and resolve the type parameters.
1750 /// We're called from Method.Define().
1752 public bool Define (MethodBuilder mb)
1754 GenericTypeParameterBuilder[] gen_params;
1755 TypeParameterName[] names = MemberName.TypeArguments.GetDeclarations ();
1756 string[] snames = new string [names.Length];
1757 for (int i = 0; i < names.Length; i++)
1758 snames [i] = names [i].Name;
1759 gen_params = mb.DefineGenericParameters (snames);
1760 for (int i = 0; i < TypeParameters.Length; i++)
1761 TypeParameters [i].Define (gen_params [i]);
1766 for (int i = 0; i < TypeParameters.Length; i++) {
1767 if (!TypeParameters [i].ResolveType (ec))
1775 /// We're called from MethodData.Define() after creating the MethodBuilder.
1777 public bool DefineType (EmitContext ec, MethodBuilder mb,
1778 MethodInfo implementing, bool is_override)
1780 for (int i = 0; i < TypeParameters.Length; i++)
1781 if (!TypeParameters [i].DefineType (
1782 ec, mb, implementing, is_override))
1786 foreach (Parameter p in parameters.FixedParameters){
1787 if (!p.Resolve (ec))
1790 if ((return_type != null) && (return_type.ResolveAsTypeTerminal (ec) == null))
1796 public void EmitAttributes (EmitContext ec)
1798 for (int i = 0; i < TypeParameters.Length; i++)
1799 TypeParameters [i].EmitAttributes (ec);
1801 if (OptAttributes != null)
1802 OptAttributes.Emit (ec, this);
1805 public override bool DefineMembers (TypeContainer parent)
1810 public override MemberList FindMembers (MemberTypes mt, BindingFlags bf,
1811 MemberFilter filter, object criteria)
1813 throw new Exception ();
1816 public override MemberCache MemberCache {
1822 public override void ApplyAttributeBuilder (Attribute a, CustomAttributeBuilder cb)
1824 base.ApplyAttributeBuilder (a, cb);
1827 public override AttributeTargets AttributeTargets {
1829 return AttributeTargets.Method | AttributeTargets.ReturnValue;
1833 public override string DocCommentHeader {
1834 get { return "M:"; }
1838 public class DefaultValueExpression : Expression
1842 public DefaultValueExpression (Expression expr, Location loc)
1848 public override Expression DoResolve (EmitContext ec)
1850 TypeExpr texpr = expr.ResolveAsTypeTerminal (ec);
1856 eclass = ExprClass.Variable;
1860 public override void Emit (EmitContext ec)
1862 if (type.IsGenericParameter || TypeManager.IsValueType (type)) {
1863 LocalTemporary temp_storage = new LocalTemporary (ec, type);
1865 temp_storage.AddressOf (ec, AddressOp.LoadStore);
1866 ec.ig.Emit (OpCodes.Initobj, type);
1867 temp_storage.Emit (ec);
1869 ec.ig.Emit (OpCodes.Ldnull);
1873 public class NullableType : TypeExpr
1875 Expression underlying;
1877 public NullableType (Expression underlying, Location l)
1879 this.underlying = underlying;
1882 eclass = ExprClass.Type;
1885 public NullableType (Type type, Location loc)
1886 : this (new TypeExpression (type, loc), loc)
1889 public override string Name {
1890 get { return underlying.ToString () + "?"; }
1893 public override string FullName {
1894 get { return underlying.ToString () + "?"; }
1897 protected override TypeExpr DoResolveAsTypeStep (EmitContext ec)
1899 TypeArguments args = new TypeArguments (loc);
1900 args.Add (underlying);
1902 ConstructedType ctype = new ConstructedType (TypeManager.generic_nullable_type, args, loc);
1903 return ctype.ResolveAsTypeTerminal (ec);
1907 public partial class TypeManager
1910 // A list of core types that the compiler requires or uses
1912 static public Type activator_type;
1913 static public Type generic_ienumerator_type;
1914 static public Type generic_ienumerable_type;
1915 static public Type generic_nullable_type;
1918 // Tracks the generic parameters.
1920 static PtrHashtable builder_to_type_param;
1923 // These methods are called by code generated by the compiler
1925 static public MethodInfo activator_create_instance;
1927 static void InitGenerics ()
1929 builder_to_type_param = new PtrHashtable ();
1932 static void CleanUpGenerics ()
1934 builder_to_type_param = null;
1937 static void InitGenericCoreTypes ()
1939 activator_type = CoreLookupType ("System", "Activator");
1941 generic_ienumerator_type = CoreLookupType (
1942 "System.Collections.Generic", "IEnumerator", 1);
1943 generic_ienumerable_type = CoreLookupType (
1944 "System.Collections.Generic", "IEnumerable", 1);
1945 generic_nullable_type = CoreLookupType (
1946 "System", "Nullable", 1);
1949 static void InitGenericCodeHelpers ()
1952 Type [] type_arg = { type_type };
1953 activator_create_instance = GetMethod (
1954 activator_type, "CreateInstance", type_arg);
1957 static Type CoreLookupType (string ns, string name, int arity)
1959 return CoreLookupType (ns, MemberName.MakeName (name, arity));
1962 public static void AddTypeParameter (Type t, TypeParameter tparam)
1964 if (!builder_to_type_param.Contains (t))
1965 builder_to_type_param.Add (t, tparam);
1968 public static TypeContainer LookupGenericTypeContainer (Type t)
1970 t = DropGenericTypeArguments (t);
1971 return LookupTypeContainer (t);
1974 public static TypeParameter LookupTypeParameter (Type t)
1976 return (TypeParameter) builder_to_type_param [t];
1979 public static GenericConstraints GetTypeParameterConstraints (Type t)
1981 if (!t.IsGenericParameter)
1982 throw new InvalidOperationException ();
1984 TypeParameter tparam = LookupTypeParameter (t);
1986 return tparam.GenericConstraints;
1988 return ReflectionConstraints.GetConstraints (t);
1991 public static bool IsGeneric (Type t)
1993 DeclSpace ds = (DeclSpace) builder_to_declspace [t];
1995 return ds.IsGeneric;
1998 public static bool HasGenericArguments (Type t)
2000 return GetNumberOfTypeArguments (t) > 0;
2003 public static int GetNumberOfTypeArguments (Type t)
2005 if (t.IsGenericParameter)
2007 DeclSpace tc = LookupDeclSpace (t);
2009 return tc.IsGeneric ? tc.CountTypeParameters : 0;
2011 return t.IsGenericType ? t.GetGenericArguments ().Length : 0;
2014 public static Type[] GetTypeArguments (Type t)
2016 DeclSpace tc = LookupDeclSpace (t);
2019 return Type.EmptyTypes;
2021 TypeParameter[] tparam = tc.TypeParameters;
2022 Type[] ret = new Type [tparam.Length];
2023 for (int i = 0; i < tparam.Length; i++) {
2024 ret [i] = tparam [i].Type;
2025 if (ret [i] == null)
2026 throw new InternalErrorException ();
2031 return t.GetGenericArguments ();
2034 public static Type DropGenericTypeArguments (Type t)
2036 if (!t.IsGenericType)
2038 // Micro-optimization: a generic typebuilder is always a generic type definition
2039 if (t is TypeBuilder)
2041 return t.GetGenericTypeDefinition ();
2045 // Whether `array' is an array of T and `enumerator' is `IEnumerable<T>'.
2046 // For instance "string[]" -> "IEnumerable<string>".
2048 public static bool IsIEnumerable (Type array, Type enumerator)
2050 if (!array.IsArray || !enumerator.IsGenericInstance)
2053 if (enumerator.GetGenericTypeDefinition () != generic_ienumerable_type)
2056 Type[] args = GetTypeArguments (enumerator);
2057 return args [0] == GetElementType (array);
2060 public static bool IsEqual (Type a, Type b)
2065 if ((a is TypeBuilder) && a.IsGenericTypeDefinition && b.IsGenericInstance) {
2067 // `a' is a generic type definition's TypeBuilder and `b' is a
2068 // generic instance of the same type.
2074 // void Test (Stack<T> stack) { }
2077 // The first argument of `Test' will be the generic instance
2078 // "Stack<!0>" - which is the same type than the "Stack" TypeBuilder.
2081 // We hit this via Closure.Filter() for gen-82.cs.
2083 if (a != b.GetGenericTypeDefinition ())
2086 Type[] aparams = a.GetGenericArguments ();
2087 Type[] bparams = b.GetGenericArguments ();
2089 if (aparams.Length != bparams.Length)
2092 for (int i = 0; i < aparams.Length; i++)
2093 if (!IsEqual (aparams [i], bparams [i]))
2099 if ((b is TypeBuilder) && b.IsGenericTypeDefinition && a.IsGenericInstance)
2100 return IsEqual (b, a);
2102 if (a.IsGenericParameter && b.IsGenericParameter) {
2103 if (a.DeclaringMethod != b.DeclaringMethod &&
2104 (a.DeclaringMethod == null || b.DeclaringMethod == null))
2106 return a.GenericParameterPosition == b.GenericParameterPosition;
2109 if (a.IsArray && b.IsArray) {
2110 if (a.GetArrayRank () != b.GetArrayRank ())
2112 return IsEqual (a.GetElementType (), b.GetElementType ());
2115 if (a.IsGenericInstance && b.IsGenericInstance) {
2116 if (a.GetGenericTypeDefinition () != b.GetGenericTypeDefinition ())
2119 Type[] aargs = a.GetGenericArguments ();
2120 Type[] bargs = b.GetGenericArguments ();
2122 if (aargs.Length != bargs.Length)
2125 for (int i = 0; i < aargs.Length; i++) {
2126 if (!IsEqual (aargs [i], bargs [i]))
2137 /// Check whether `a' and `b' may become equal generic types.
2138 /// The algorithm to do that is a little bit complicated.
2140 public static bool MayBecomeEqualGenericTypes (Type a, Type b, Type[] class_infered,
2141 Type[] method_infered)
2143 if (a.IsGenericParameter) {
2145 // If a is an array of a's type, they may never
2149 b = b.GetElementType ();
2155 // If b is a generic parameter or an actual type,
2156 // they may become equal:
2158 // class X<T,U> : I<T>, I<U>
2159 // class X<T> : I<T>, I<float>
2161 if (b.IsGenericParameter || !b.IsGenericInstance) {
2162 int pos = a.GenericParameterPosition;
2163 Type[] args = a.DeclaringMethod != null ? method_infered : class_infered;
2164 if (args [pos] == null) {
2169 return args [pos] == a;
2173 // We're now comparing a type parameter with a
2174 // generic instance. They may become equal unless
2175 // the type parameter appears anywhere in the
2176 // generic instance:
2178 // class X<T,U> : I<T>, I<X<U>>
2179 // -> error because you could instanciate it as
2182 // class X<T> : I<T>, I<X<T>> -> ok
2185 Type[] bargs = GetTypeArguments (b);
2186 for (int i = 0; i < bargs.Length; i++) {
2187 if (a.Equals (bargs [i]))
2194 if (b.IsGenericParameter)
2195 return MayBecomeEqualGenericTypes (b, a, class_infered, method_infered);
2198 // At this point, neither a nor b are a type parameter.
2200 // If one of them is a generic instance, let
2201 // MayBecomeEqualGenericInstances() compare them (if the
2202 // other one is not a generic instance, they can never
2206 if (a.IsGenericInstance || b.IsGenericInstance)
2207 return MayBecomeEqualGenericInstances (a, b, class_infered, method_infered);
2210 // If both of them are arrays.
2213 if (a.IsArray && b.IsArray) {
2214 if (a.GetArrayRank () != b.GetArrayRank ())
2217 a = a.GetElementType ();
2218 b = b.GetElementType ();
2220 return MayBecomeEqualGenericTypes (a, b, class_infered, method_infered);
2224 // Ok, two ordinary types.
2227 return a.Equals (b);
2231 // Checks whether two generic instances may become equal for some
2232 // particular instantiation (26.3.1).
2234 public static bool MayBecomeEqualGenericInstances (Type a, Type b,
2235 Type[] class_infered,
2236 Type[] method_infered)
2238 if (!a.IsGenericInstance || !b.IsGenericInstance)
2240 if (a.GetGenericTypeDefinition () != b.GetGenericTypeDefinition ())
2243 return MayBecomeEqualGenericInstances (
2244 GetTypeArguments (a), GetTypeArguments (b), class_infered, method_infered);
2247 public static bool MayBecomeEqualGenericInstances (Type[] aargs, Type[] bargs,
2248 Type[] class_infered,
2249 Type[] method_infered)
2251 if (aargs.Length != bargs.Length)
2254 for (int i = 0; i < aargs.Length; i++) {
2255 if (!MayBecomeEqualGenericTypes (aargs [i], bargs [i], class_infered, method_infered))
2263 /// Check whether `type' and `parent' are both instantiations of the same
2264 /// generic type. Note that we do not check the type parameters here.
2266 public static bool IsInstantiationOfSameGenericType (Type type, Type parent)
2268 int tcount = GetNumberOfTypeArguments (type);
2269 int pcount = GetNumberOfTypeArguments (parent);
2271 if (tcount != pcount)
2274 type = DropGenericTypeArguments (type);
2275 parent = DropGenericTypeArguments (parent);
2277 return type.Equals (parent);
2281 /// Whether `mb' is a generic method definition.
2283 public static bool IsGenericMethod (MethodBase mb)
2285 if (mb.DeclaringType is TypeBuilder) {
2286 IMethodData method = (IMethodData) builder_to_method [mb];
2290 return method.GenericMethod != null;
2293 return mb.IsGenericMethodDefinition;
2300 static bool InferType (Type pt, Type at, Type[] infered)
2302 if (pt.IsGenericParameter && (pt.DeclaringMethod != null)) {
2303 int pos = pt.GenericParameterPosition;
2305 if (infered [pos] == null) {
2307 while (check.IsArray)
2308 check = check.GetElementType ();
2317 if (infered [pos] != at)
2323 if (!pt.ContainsGenericParameters) {
2324 if (at.ContainsGenericParameters)
2325 return InferType (at, pt, infered);
2332 (at.GetArrayRank () != pt.GetArrayRank ()))
2335 return InferType (pt.GetElementType (), at.GetElementType (), infered);
2340 (pt.GetArrayRank () != at.GetArrayRank ()))
2343 return InferType (pt.GetElementType (), at.GetElementType (), infered);
2346 if (pt.IsByRef && at.IsByRef)
2347 return InferType (pt.GetElementType (), at.GetElementType (), infered);
2348 ArrayList list = new ArrayList ();
2349 if (at.IsGenericInstance)
2351 for (Type bt = at.BaseType; bt != null; bt = bt.BaseType)
2354 list.AddRange (TypeManager.GetInterfaces (at));
2356 bool found_one = false;
2358 foreach (Type type in list) {
2359 if (!type.IsGenericInstance)
2362 Type[] infered_types = new Type [infered.Length];
2364 if (!InferGenericInstance (pt, type, infered_types))
2367 for (int i = 0; i < infered_types.Length; i++) {
2368 if (infered [i] == null) {
2369 infered [i] = infered_types [i];
2373 if (infered [i] != infered_types [i])
2383 static bool InferGenericInstance (Type pt, Type at, Type[] infered_types)
2385 Type[] at_args = at.GetGenericArguments ();
2386 Type[] pt_args = pt.GetGenericArguments ();
2388 if (at_args.Length != pt_args.Length)
2391 for (int i = 0; i < at_args.Length; i++) {
2392 if (!InferType (pt_args [i], at_args [i], infered_types))
2396 for (int i = 0; i < infered_types.Length; i++) {
2397 if (infered_types [i] == null)
2405 /// Type inference. Try to infer the type arguments from the params method
2406 /// `method', which is invoked with the arguments `arguments'. This is used
2407 /// when resolving an Invocation or a DelegateInvocation and the user
2408 /// did not explicitly specify type arguments.
2410 public static bool InferParamsTypeArguments (EmitContext ec, ArrayList arguments,
2411 ref MethodBase method)
2413 if ((arguments == null) || !TypeManager.IsGenericMethod (method))
2418 if (arguments == null)
2421 arg_count = arguments.Count;
2423 ParameterData pd = TypeManager.GetParameterData (method);
2425 int pd_count = pd.Count;
2430 if (pd.ParameterModifier (pd_count - 1) != Parameter.Modifier.PARAMS)
2433 if (pd_count - 1 > arg_count)
2436 if (pd_count == 1 && arg_count == 0)
2439 Type[] method_args = method.GetGenericArguments ();
2440 Type[] infered_types = new Type [method_args.Length];
2443 // If we have come this far, the case which
2444 // remains is when the number of parameters is
2445 // less than or equal to the argument count.
2447 for (int i = 0; i < pd_count - 1; ++i) {
2448 Argument a = (Argument) arguments [i];
2450 if ((a.Expr is NullLiteral) || (a.Expr is MethodGroupExpr))
2453 Type pt = pd.ParameterType (i);
2456 if (!InferType (pt, at, infered_types))
2460 Type element_type = TypeManager.GetElementType (pd.ParameterType (pd_count - 1));
2462 for (int i = pd_count - 1; i < arg_count; i++) {
2463 Argument a = (Argument) arguments [i];
2465 if ((a.Expr is NullLiteral) || (a.Expr is MethodGroupExpr))
2468 if (!InferType (element_type, a.Type, infered_types))
2472 for (int i = 0; i < infered_types.Length; i++)
2473 if (infered_types [i] == null)
2476 method = ((MethodInfo)method).MakeGenericMethod (infered_types);
2480 static bool InferTypeArguments (Type[] param_types, Type[] arg_types,
2481 Type[] infered_types)
2483 if (infered_types == null)
2486 for (int i = 0; i < arg_types.Length; i++) {
2487 if (arg_types [i] == null)
2490 if (!InferType (param_types [i], arg_types [i], infered_types))
2494 for (int i = 0; i < infered_types.Length; i++)
2495 if (infered_types [i] == null)
2502 /// Type inference. Try to infer the type arguments from `method',
2503 /// which is invoked with the arguments `arguments'. This is used
2504 /// when resolving an Invocation or a DelegateInvocation and the user
2505 /// did not explicitly specify type arguments.
2507 public static bool InferTypeArguments (EmitContext ec, ArrayList arguments,
2508 ref MethodBase method)
2510 if (!TypeManager.IsGenericMethod (method))
2514 if (arguments != null)
2515 arg_count = arguments.Count;
2519 ParameterData pd = TypeManager.GetParameterData (method);
2520 if (arg_count != pd.Count)
2523 Type[] method_args = method.GetGenericArguments ();
2525 bool is_open = false;
2526 for (int i = 0; i < method_args.Length; i++) {
2527 if (method_args [i].IsGenericParameter) {
2535 Type[] infered_types = new Type [method_args.Length];
2537 Type[] param_types = new Type [pd.Count];
2538 Type[] arg_types = new Type [pd.Count];
2540 for (int i = 0; i < arg_count; i++) {
2541 param_types [i] = pd.ParameterType (i);
2543 Argument a = (Argument) arguments [i];
2544 if ((a.Expr is NullLiteral) || (a.Expr is MethodGroupExpr) ||
2545 (a.Expr is AnonymousMethod))
2548 arg_types [i] = a.Type;
2551 if (!InferTypeArguments (param_types, arg_types, infered_types))
2554 method = ((MethodInfo)method).MakeGenericMethod (infered_types);
2561 public static bool InferTypeArguments (EmitContext ec, ParameterData apd,
2562 ref MethodBase method)
2564 if (!TypeManager.IsGenericMethod (method))
2567 ParameterData pd = TypeManager.GetParameterData (method);
2568 if (apd.Count != pd.Count)
2571 Type[] method_args = method.GetGenericArguments ();
2572 Type[] infered_types = new Type [method_args.Length];
2574 Type[] param_types = new Type [pd.Count];
2575 Type[] arg_types = new Type [pd.Count];
2577 for (int i = 0; i < apd.Count; i++) {
2578 param_types [i] = pd.ParameterType (i);
2579 arg_types [i] = apd.ParameterType (i);
2582 if (!InferTypeArguments (param_types, arg_types, infered_types))
2585 method = ((MethodInfo)method).MakeGenericMethod (infered_types);
2589 public static bool IsNullableType (Type t)
2591 return generic_nullable_type == DropGenericTypeArguments (t);
2595 public abstract class Nullable
2597 protected sealed class NullableInfo
2599 public readonly Type Type;
2600 public readonly Type UnderlyingType;
2601 public readonly MethodInfo HasValue;
2602 public readonly MethodInfo Value;
2603 public readonly ConstructorInfo Constructor;
2605 public NullableInfo (Type type)
2608 UnderlyingType = TypeManager.GetTypeArguments (type) [0];
2610 PropertyInfo has_value_pi = TypeManager.GetProperty (type, "HasValue");
2611 PropertyInfo value_pi = TypeManager.GetProperty (type, "Value");
2613 HasValue = has_value_pi.GetGetMethod (false);
2614 Value = value_pi.GetGetMethod (false);
2615 Constructor = type.GetConstructor (new Type[] { UnderlyingType });
2619 protected class Unwrap : Expression, IMemoryLocation, IAssignMethod
2624 LocalTemporary temp;
2627 public Unwrap (Expression expr, Location loc)
2633 public override Expression DoResolve (EmitContext ec)
2635 expr = expr.Resolve (ec);
2639 if (!(expr is IMemoryLocation))
2640 temp = new LocalTemporary (ec, expr.Type);
2642 info = new NullableInfo (expr.Type);
2643 type = info.UnderlyingType;
2644 eclass = expr.eclass;
2648 public override void Emit (EmitContext ec)
2650 AddressOf (ec, AddressOp.LoadStore);
2651 ec.ig.EmitCall (OpCodes.Call, info.Value, null);
2654 public void EmitCheck (EmitContext ec)
2656 AddressOf (ec, AddressOp.LoadStore);
2657 ec.ig.EmitCall (OpCodes.Call, info.HasValue, null);
2660 void create_temp (EmitContext ec)
2662 if ((temp != null) && !has_temp) {
2669 public void AddressOf (EmitContext ec, AddressOp mode)
2673 temp.AddressOf (ec, AddressOp.LoadStore);
2675 ((IMemoryLocation) expr).AddressOf (ec, AddressOp.LoadStore);
2678 public void Emit (EmitContext ec, bool leave_copy)
2691 public void EmitAssign (EmitContext ec, Expression source,
2692 bool leave_copy, bool prepare_for_load)
2695 ec.ig.Emit (OpCodes.Newobj, info.Constructor);
2698 ec.ig.Emit (OpCodes.Dup);
2700 Expression empty = new EmptyExpression (expr.Type);
2701 ((IAssignMethod) expr).EmitAssign (ec, empty, false, prepare_for_load);
2705 protected class Wrap : Expression
2710 public Wrap (Expression expr, Location loc)
2716 public override Expression DoResolve (EmitContext ec)
2718 expr = expr.Resolve (ec);
2722 TypeExpr target_type = new NullableType (expr.Type, loc);
2723 target_type = target_type.ResolveAsTypeTerminal (ec);
2724 if (target_type == null)
2727 type = target_type.Type;
2728 info = new NullableInfo (type);
2729 eclass = ExprClass.Value;
2733 public override void Emit (EmitContext ec)
2736 ec.ig.Emit (OpCodes.Newobj, info.Constructor);
2740 public class NullableLiteral : Expression, IMemoryLocation {
2741 public NullableLiteral (Type target_type, Location loc)
2743 this.type = target_type;
2746 eclass = ExprClass.Value;
2749 public override Expression DoResolve (EmitContext ec)
2754 public override void Emit (EmitContext ec)
2756 LocalTemporary value_target = new LocalTemporary (ec, type);
2758 value_target.AddressOf (ec, AddressOp.Store);
2759 ec.ig.Emit (OpCodes.Initobj, type);
2760 value_target.Emit (ec);
2763 public void AddressOf (EmitContext ec, AddressOp Mode)
2765 LocalTemporary value_target = new LocalTemporary (ec, type);
2767 value_target.AddressOf (ec, AddressOp.Store);
2768 ec.ig.Emit (OpCodes.Initobj, type);
2769 ((IMemoryLocation) value_target).AddressOf (ec, Mode);
2773 public abstract class Lifted : Expression, IMemoryLocation
2775 Expression expr, underlying, wrap, null_value;
2778 protected Lifted (Expression expr, Location loc)
2784 public override Expression DoResolve (EmitContext ec)
2786 expr = expr.Resolve (ec);
2790 unwrap = (Unwrap) new Unwrap (expr, loc).Resolve (ec);
2794 underlying = ResolveUnderlying (unwrap, ec);
2795 if (underlying == null)
2798 wrap = new Wrap (underlying, loc).Resolve (ec);
2802 null_value = new NullableLiteral (wrap.Type, loc).Resolve (ec);
2803 if (null_value == null)
2807 eclass = ExprClass.Value;
2811 protected abstract Expression ResolveUnderlying (Expression unwrap, EmitContext ec);
2813 public override void Emit (EmitContext ec)
2815 ILGenerator ig = ec.ig;
2816 Label is_null_label = ig.DefineLabel ();
2817 Label end_label = ig.DefineLabel ();
2819 unwrap.EmitCheck (ec);
2820 ig.Emit (OpCodes.Brfalse, is_null_label);
2823 ig.Emit (OpCodes.Br, end_label);
2825 ig.MarkLabel (is_null_label);
2826 null_value.Emit (ec);
2828 ig.MarkLabel (end_label);
2831 public void AddressOf (EmitContext ec, AddressOp mode)
2833 unwrap.AddressOf (ec, mode);
2837 public class LiftedConversion : Lifted
2839 public readonly bool IsUser;
2840 public readonly bool IsExplicit;
2841 public readonly Type TargetType;
2843 public LiftedConversion (Expression expr, Type target_type, bool is_user,
2844 bool is_explicit, Location loc)
2847 this.IsUser = is_user;
2848 this.IsExplicit = is_explicit;
2849 this.TargetType = target_type;
2852 protected override Expression ResolveUnderlying (Expression unwrap, EmitContext ec)
2854 Type type = TypeManager.GetTypeArguments (TargetType) [0];
2857 return Convert.UserDefinedConversion (ec, unwrap, type, loc, IsExplicit);
2860 return Convert.ExplicitConversion (ec, unwrap, type, loc);
2862 return Convert.ImplicitConversion (ec, unwrap, type, loc);
2867 public class LiftedUnaryOperator : Lifted
2869 public readonly Unary.Operator Oper;
2871 public LiftedUnaryOperator (Unary.Operator op, Expression expr, Location loc)
2877 protected override Expression ResolveUnderlying (Expression unwrap, EmitContext ec)
2879 return new Unary (Oper, unwrap, loc);
2883 public class LiftedConditional : Lifted
2885 Expression true_expr, false_expr;
2887 public LiftedConditional (Expression expr, Expression true_expr, Expression false_expr,
2891 this.true_expr = true_expr;
2892 this.false_expr = false_expr;
2895 protected override Expression ResolveUnderlying (Expression unwrap, EmitContext ec)
2897 return new Conditional (unwrap, true_expr, false_expr);
2901 public class LiftedBinaryOperator : Expression
2903 public readonly Binary.Operator Oper;
2905 Expression left, right, underlying, null_value, bool_wrap;
2906 Unwrap left_unwrap, right_unwrap;
2907 bool is_equality, is_comparision, is_boolean;
2909 public LiftedBinaryOperator (Binary.Operator op, Expression left, Expression right,
2918 public override Expression DoResolve (EmitContext ec)
2920 if (TypeManager.IsNullableType (left.Type)) {
2921 left_unwrap = new Unwrap (left, loc);
2922 left = left_unwrap.Resolve (ec);
2927 if (TypeManager.IsNullableType (right.Type)) {
2928 right_unwrap = new Unwrap (right, loc);
2929 right = right_unwrap.Resolve (ec);
2934 if (((Oper == Binary.Operator.BitwiseAnd) || (Oper == Binary.Operator.BitwiseOr) ||
2935 (Oper == Binary.Operator.LogicalAnd) || (Oper == Binary.Operator.LogicalOr)) &&
2936 ((left.Type == TypeManager.bool_type) && (right.Type == TypeManager.bool_type))) {
2937 Expression empty = new EmptyExpression (TypeManager.bool_type);
2938 bool_wrap = new Wrap (empty, loc).Resolve (ec);
2939 null_value = new NullableLiteral (bool_wrap.Type, loc).Resolve (ec);
2941 type = bool_wrap.Type;
2943 } else if ((Oper == Binary.Operator.Equality) || (Oper == Binary.Operator.Inequality)) {
2944 if (!(left is NullLiteral) && !(right is NullLiteral)) {
2945 underlying = new Binary (Oper, left, right).Resolve (ec);
2946 if (underlying == null)
2950 type = TypeManager.bool_type;
2952 } else if ((Oper == Binary.Operator.LessThan) ||
2953 (Oper == Binary.Operator.GreaterThan) ||
2954 (Oper == Binary.Operator.LessThanOrEqual) ||
2955 (Oper == Binary.Operator.GreaterThanOrEqual)) {
2956 underlying = new Binary (Oper, left, right).Resolve (ec);
2957 if (underlying == null)
2960 type = TypeManager.bool_type;
2961 is_comparision = true;
2963 underlying = new Binary (Oper, left, right).Resolve (ec);
2964 if (underlying == null)
2967 underlying = new Wrap (underlying, loc).Resolve (ec);
2968 if (underlying == null)
2971 type = underlying.Type;
2972 null_value = new NullableLiteral (type, loc).Resolve (ec);
2975 eclass = ExprClass.Value;
2979 void EmitBoolean (EmitContext ec)
2981 ILGenerator ig = ec.ig;
2983 Label left_is_null_label = ig.DefineLabel ();
2984 Label right_is_null_label = ig.DefineLabel ();
2985 Label is_null_label = ig.DefineLabel ();
2986 Label wrap_label = ig.DefineLabel ();
2987 Label end_label = ig.DefineLabel ();
2989 if (left_unwrap != null) {
2990 left_unwrap.EmitCheck (ec);
2991 ig.Emit (OpCodes.Brfalse, left_is_null_label);
2995 ig.Emit (OpCodes.Dup);
2996 if ((Oper == Binary.Operator.BitwiseOr) || (Oper == Binary.Operator.LogicalOr))
2997 ig.Emit (OpCodes.Brtrue, wrap_label);
2999 ig.Emit (OpCodes.Brfalse, wrap_label);
3001 if (right_unwrap != null) {
3002 right_unwrap.EmitCheck (ec);
3003 ig.Emit (OpCodes.Brfalse, right_is_null_label);
3006 if ((Oper == Binary.Operator.LogicalAnd) || (Oper == Binary.Operator.LogicalOr))
3007 ig.Emit (OpCodes.Pop);
3010 if (Oper == Binary.Operator.BitwiseOr)
3011 ig.Emit (OpCodes.Or);
3012 else if (Oper == Binary.Operator.BitwiseAnd)
3013 ig.Emit (OpCodes.And);
3014 ig.Emit (OpCodes.Br, wrap_label);
3016 ig.MarkLabel (left_is_null_label);
3017 if (right_unwrap != null) {
3018 right_unwrap.EmitCheck (ec);
3019 ig.Emit (OpCodes.Brfalse, is_null_label);
3023 ig.Emit (OpCodes.Dup);
3024 if ((Oper == Binary.Operator.BitwiseOr) || (Oper == Binary.Operator.LogicalOr))
3025 ig.Emit (OpCodes.Brtrue, wrap_label);
3027 ig.Emit (OpCodes.Brfalse, wrap_label);
3029 ig.MarkLabel (right_is_null_label);
3030 ig.Emit (OpCodes.Pop);
3031 ig.MarkLabel (is_null_label);
3032 null_value.Emit (ec);
3033 ig.Emit (OpCodes.Br, end_label);
3035 ig.MarkLabel (wrap_label);
3036 ig.Emit (OpCodes.Nop);
3037 bool_wrap.Emit (ec);
3038 ig.Emit (OpCodes.Nop);
3040 ig.MarkLabel (end_label);
3043 void EmitEquality (EmitContext ec)
3045 ILGenerator ig = ec.ig;
3047 Label left_not_null_label = ig.DefineLabel ();
3048 Label false_label = ig.DefineLabel ();
3049 Label true_label = ig.DefineLabel ();
3050 Label end_label = ig.DefineLabel ();
3052 bool false_label_used = false;
3053 bool true_label_used = false;
3055 if (left_unwrap != null) {
3056 left_unwrap.EmitCheck (ec);
3057 if (right is NullLiteral) {
3058 if (Oper == Binary.Operator.Equality) {
3059 true_label_used = true;
3060 ig.Emit (OpCodes.Brfalse, true_label);
3062 false_label_used = true;
3063 ig.Emit (OpCodes.Brfalse, false_label);
3065 } else if (right_unwrap != null) {
3066 ig.Emit (OpCodes.Dup);
3067 ig.Emit (OpCodes.Brtrue, left_not_null_label);
3068 right_unwrap.EmitCheck (ec);
3069 ig.Emit (OpCodes.Ceq);
3070 if (Oper == Binary.Operator.Inequality) {
3071 ig.Emit (OpCodes.Ldc_I4_0);
3072 ig.Emit (OpCodes.Ceq);
3074 ig.Emit (OpCodes.Br, end_label);
3076 ig.MarkLabel (left_not_null_label);
3077 ig.Emit (OpCodes.Pop);
3079 if (Oper == Binary.Operator.Equality) {
3080 false_label_used = true;
3081 ig.Emit (OpCodes.Brfalse, false_label);
3083 true_label_used = true;
3084 ig.Emit (OpCodes.Brfalse, true_label);
3089 if (right_unwrap != null) {
3090 right_unwrap.EmitCheck (ec);
3091 if (left is NullLiteral) {
3092 if (Oper == Binary.Operator.Equality) {
3093 true_label_used = true;
3094 ig.Emit (OpCodes.Brfalse, true_label);
3096 false_label_used = true;
3097 ig.Emit (OpCodes.Brfalse, false_label);
3100 if (Oper == Binary.Operator.Equality) {
3101 false_label_used = true;
3102 ig.Emit (OpCodes.Brfalse, false_label);
3104 true_label_used = true;
3105 ig.Emit (OpCodes.Brfalse, true_label);
3110 bool left_is_null = left is NullLiteral;
3111 bool right_is_null = right is NullLiteral;
3112 if (left_is_null || right_is_null) {
3113 if (((Oper == Binary.Operator.Equality) && (left_is_null == right_is_null)) ||
3114 ((Oper == Binary.Operator.Inequality) && (left_is_null != right_is_null))) {
3115 true_label_used = true;
3116 ig.Emit (OpCodes.Br, true_label);
3118 false_label_used = true;
3119 ig.Emit (OpCodes.Br, false_label);
3122 underlying.Emit (ec);
3123 ig.Emit (OpCodes.Br, end_label);
3126 ig.MarkLabel (false_label);
3127 if (false_label_used) {
3128 ig.Emit (OpCodes.Ldc_I4_0);
3129 if (true_label_used)
3130 ig.Emit (OpCodes.Br, end_label);
3133 ig.MarkLabel (true_label);
3134 if (true_label_used)
3135 ig.Emit (OpCodes.Ldc_I4_1);
3137 ig.MarkLabel (end_label);
3140 void EmitComparision (EmitContext ec)
3142 ILGenerator ig = ec.ig;
3144 Label is_null_label = ig.DefineLabel ();
3145 Label end_label = ig.DefineLabel ();
3147 if (left_unwrap != null) {
3148 left_unwrap.EmitCheck (ec);
3149 ig.Emit (OpCodes.Brfalse, is_null_label);
3152 if (right_unwrap != null) {
3153 right_unwrap.EmitCheck (ec);
3154 ig.Emit (OpCodes.Brfalse, is_null_label);
3157 underlying.Emit (ec);
3158 ig.Emit (OpCodes.Br, end_label);
3160 ig.MarkLabel (is_null_label);
3161 ig.Emit (OpCodes.Ldc_I4_0);
3163 ig.MarkLabel (end_label);
3166 public override void Emit (EmitContext ec)
3171 } else if (is_equality) {
3174 } else if (is_comparision) {
3175 EmitComparision (ec);
3179 ILGenerator ig = ec.ig;
3181 Label is_null_label = ig.DefineLabel ();
3182 Label end_label = ig.DefineLabel ();
3184 if (left_unwrap != null) {
3185 left_unwrap.EmitCheck (ec);
3186 ig.Emit (OpCodes.Brfalse, is_null_label);
3189 if (right_unwrap != null) {
3190 right_unwrap.EmitCheck (ec);
3191 ig.Emit (OpCodes.Brfalse, is_null_label);
3194 underlying.Emit (ec);
3195 ig.Emit (OpCodes.Br, end_label);
3197 ig.MarkLabel (is_null_label);
3198 null_value.Emit (ec);
3200 ig.MarkLabel (end_label);
3204 public class OperatorTrueOrFalse : Expression
3206 public readonly bool IsTrue;
3211 public OperatorTrueOrFalse (Expression expr, bool is_true, Location loc)
3213 this.IsTrue = is_true;
3218 public override Expression DoResolve (EmitContext ec)
3220 unwrap = new Unwrap (expr, loc);
3221 expr = unwrap.Resolve (ec);
3225 if (unwrap.Type != TypeManager.bool_type)
3228 type = TypeManager.bool_type;
3229 eclass = ExprClass.Value;
3233 public override void Emit (EmitContext ec)
3235 ILGenerator ig = ec.ig;
3237 Label is_null_label = ig.DefineLabel ();
3238 Label end_label = ig.DefineLabel ();
3240 unwrap.EmitCheck (ec);
3241 ig.Emit (OpCodes.Brfalse, is_null_label);
3245 ig.Emit (OpCodes.Ldc_I4_0);
3246 ig.Emit (OpCodes.Ceq);
3248 ig.Emit (OpCodes.Br, end_label);
3250 ig.MarkLabel (is_null_label);
3251 ig.Emit (OpCodes.Ldc_I4_0);
3253 ig.MarkLabel (end_label);
3257 public class NullCoalescingOperator : Expression
3259 Expression left, right;
3263 public NullCoalescingOperator (Expression left, Expression right, Location loc)
3269 eclass = ExprClass.Value;
3272 public override Expression DoResolve (EmitContext ec)
3277 left = left.Resolve (ec);
3281 right = right.Resolve (ec);
3285 Type ltype = left.Type, rtype = right.Type;
3287 if (!TypeManager.IsNullableType (ltype) && ltype.IsValueType) {
3288 Binary.Error_OperatorCannotBeApplied (loc, "??", ltype, rtype);
3292 if (TypeManager.IsNullableType (ltype)) {
3293 NullableInfo info = new NullableInfo (ltype);
3295 unwrap = (Unwrap) new Unwrap (left, loc).Resolve (ec);
3299 expr = Convert.ImplicitConversion (ec, right, info.UnderlyingType, loc);
3307 expr = Convert.ImplicitConversion (ec, right, ltype, loc);
3313 if (unwrap != null) {
3314 expr = Convert.ImplicitConversion (ec, unwrap, rtype, loc);
3323 Binary.Error_OperatorCannotBeApplied (loc, "??", ltype, rtype);
3327 public override void Emit (EmitContext ec)
3329 ILGenerator ig = ec.ig;
3331 Label is_null_label = ig.DefineLabel ();
3332 Label end_label = ig.DefineLabel ();
3334 if (unwrap != null) {
3335 unwrap.EmitCheck (ec);
3336 ig.Emit (OpCodes.Brfalse, is_null_label);
3339 ig.Emit (OpCodes.Br, end_label);
3341 ig.MarkLabel (is_null_label);
3344 ig.MarkLabel (end_label);
3347 ig.Emit (OpCodes.Dup);
3348 ig.Emit (OpCodes.Brtrue, end_label);
3350 ig.MarkLabel (is_null_label);
3352 ig.Emit (OpCodes.Pop);
3355 ig.MarkLabel (end_label);
3360 public class LiftedUnaryMutator : ExpressionStatement
3362 public readonly UnaryMutator.Mode Mode;
3363 Expression expr, null_value;
3364 UnaryMutator underlying;
3367 public LiftedUnaryMutator (UnaryMutator.Mode mode, Expression expr, Location loc)
3373 eclass = ExprClass.Value;
3376 public override Expression DoResolve (EmitContext ec)
3378 expr = expr.Resolve (ec);
3382 unwrap = (Unwrap) new Unwrap (expr, loc).Resolve (ec);
3386 underlying = (UnaryMutator) new UnaryMutator (Mode, unwrap, loc).Resolve (ec);
3387 if (underlying == null)
3390 null_value = new NullableLiteral (expr.Type, loc).Resolve (ec);
3391 if (null_value == null)
3398 void DoEmit (EmitContext ec, bool is_expr)
3400 ILGenerator ig = ec.ig;
3401 Label is_null_label = ig.DefineLabel ();
3402 Label end_label = ig.DefineLabel ();
3404 unwrap.EmitCheck (ec);
3405 ig.Emit (OpCodes.Brfalse, is_null_label);
3408 underlying.Emit (ec);
3410 underlying.EmitStatement (ec);
3411 ig.Emit (OpCodes.Br, end_label);
3413 ig.MarkLabel (is_null_label);
3415 null_value.Emit (ec);
3417 ig.MarkLabel (end_label);
3420 public override void Emit (EmitContext ec)
3425 public override void EmitStatement (EmitContext ec)