2 // ecore.cs: Core of the Expression representation for the intermediate tree.
5 // Miguel de Icaza (miguel@ximian.com)
6 // Marek Safar (marek.safar@gmail.com)
8 // Copyright 2001, 2002, 2003 Ximian, Inc.
9 // Copyright 2003-2008 Novell, Inc.
10 // Copyright 2011-2012 Xamarin Inc.
15 using System.Collections.Generic;
17 using SLE = System.Linq.Expressions;
21 using IKVM.Reflection;
22 using IKVM.Reflection.Emit;
24 using System.Reflection;
25 using System.Reflection.Emit;
28 namespace Mono.CSharp {
31 /// The ExprClass class contains the is used to pass the
32 /// classification of an expression (value, variable, namespace,
33 /// type, method group, property access, event access, indexer access,
36 public enum ExprClass : byte {
52 /// This is used to tell Resolve in which types of expressions we're
56 public enum ResolveFlags {
57 // Returns Value, Variable, PropertyAccess, EventAccess or IndexerAccess.
60 // Returns a type expression.
63 // Returns a method group.
66 TypeParameter = 1 << 3,
68 // Mask of all the expression class flags.
69 MaskExprClass = VariableOrValue | Type | MethodGroup | TypeParameter,
73 // This is just as a hint to AddressOf of what will be done with the
76 public enum AddressOp {
83 /// This interface is implemented by variables
85 public interface IMemoryLocation {
87 /// The AddressOf method should generate code that loads
88 /// the address of the object and leaves it on the stack.
90 /// The `mode' argument is used to notify the expression
91 /// of whether this will be used to read from the address or
92 /// write to the address.
94 /// This is just a hint that can be used to provide good error
95 /// reporting, and should have no other side effects.
97 void AddressOf (EmitContext ec, AddressOp mode);
101 // An expressions resolved as a direct variable reference
103 public interface IVariableReference : IFixedExpression
105 bool IsHoisted { get; }
107 VariableInfo VariableInfo { get; }
109 void SetHasAddressTaken ();
113 // Implemented by an expression which could be or is always
116 public interface IFixedExpression
118 bool IsFixed { get; }
121 public interface IExpressionCleanup
123 void EmitCleanup (EmitContext ec);
127 /// Base class for expressions
129 public abstract class Expression {
130 public ExprClass eclass;
131 protected TypeSpec type;
132 protected Location loc;
134 public TypeSpec Type {
136 set { type = value; }
139 public virtual bool IsSideEffectFree {
145 public Location Location {
149 public virtual bool IsNull {
156 // Used to workaround parser limitation where we cannot get
157 // start of statement expression location
159 public virtual Location StartLocation {
165 public virtual MethodGroupExpr CanReduceLambda (AnonymousMethodBody body)
168 // Return method-group expression when the expression can be used as
169 // lambda replacement. A good example is array sorting where instead of
172 // Array.Sort (s, (a, b) => String.Compare (a, b));
174 // we can use method group directly
176 // Array.Sort (s, String.Compare);
178 // Correct overload will be used because we do the reduction after
179 // best candidate was found.
185 // Returns true when the expression during Emit phase breaks stack
186 // by using await expression
188 public virtual bool ContainsEmitWithAwait ()
194 /// Performs semantic analysis on the Expression
198 /// The Resolve method is invoked to perform the semantic analysis
201 /// The return value is an expression (it can be the
202 /// same expression in some cases) or a new
203 /// expression that better represents this node.
205 /// For example, optimizations of Unary (LiteralInt)
206 /// would return a new LiteralInt with a negated
209 /// If there is an error during semantic analysis,
210 /// then an error should be reported (using Report)
211 /// and a null value should be returned.
213 /// There are two side effects expected from calling
214 /// Resolve(): the the field variable "eclass" should
215 /// be set to any value of the enumeration
216 /// `ExprClass' and the type variable should be set
217 /// to a valid type (this is the type of the
220 protected abstract Expression DoResolve (ResolveContext rc);
222 public virtual Expression DoResolveLValue (ResolveContext rc, Expression right_side)
228 // This is used if the expression should be resolved as a type or namespace name.
229 // the default implementation fails.
231 public virtual TypeSpec ResolveAsType (IMemberContext mc, bool allowUnboundTypeArguments = false)
233 var rc = mc as ResolveContext ?? new ResolveContext (mc);
234 Expression e = Resolve (rc);
236 e.Error_UnexpectedKind (rc, ResolveFlags.Type, loc);
241 public static void ErrorIsInaccesible (IMemberContext rc, string member, Location loc)
243 rc.Module.Compiler.Report.Error (122, loc, "`{0}' is inaccessible due to its protection level", member);
246 public void Error_ExpressionMustBeConstant (ResolveContext rc, Location loc, string e_name)
248 rc.Report.Error (133, loc, "The expression being assigned to `{0}' must be constant", e_name);
251 public void Error_ConstantCanBeInitializedWithNullOnly (ResolveContext rc, TypeSpec type, Location loc, string name)
253 rc.Report.Error (134, loc, "A constant `{0}' of reference type `{1}' can only be initialized with null",
254 name, type.GetSignatureForError ());
257 protected virtual void Error_InvalidExpressionStatement (Report report, Location loc)
259 report.Error (201, loc, "Only assignment, call, increment, decrement, await, and new object expressions can be used as a statement");
262 public void Error_InvalidExpressionStatement (BlockContext bc)
264 Error_InvalidExpressionStatement (bc.Report, loc);
267 public void Error_InvalidExpressionStatement (Report report)
269 Error_InvalidExpressionStatement (report, loc);
272 public static void Error_VoidInvalidInTheContext (Location loc, Report Report)
274 Report.Error (1547, loc, "Keyword `void' cannot be used in this context");
277 public virtual void Error_ValueCannotBeConverted (ResolveContext ec, TypeSpec target, bool expl)
279 Error_ValueCannotBeConvertedCore (ec, loc, target, expl);
282 protected void Error_ValueCannotBeConvertedCore (ResolveContext ec, Location loc, TypeSpec target, bool expl)
284 // The error was already reported as CS1660
285 if (type == InternalType.AnonymousMethod)
288 if (type == InternalType.ErrorType || target == InternalType.ErrorType)
291 string from_type = type.GetSignatureForError ();
292 string to_type = target.GetSignatureForError ();
293 if (from_type == to_type) {
294 from_type = type.GetSignatureForErrorIncludingAssemblyName ();
295 to_type = target.GetSignatureForErrorIncludingAssemblyName ();
299 ec.Report.Error (30, loc, "Cannot convert type `{0}' to `{1}'",
304 ec.Report.DisableReporting ();
305 bool expl_exists = Convert.ExplicitConversion (ec, this, target, Location.Null) != null;
306 ec.Report.EnableReporting ();
309 ec.Report.Error (266, loc,
310 "Cannot implicitly convert type `{0}' to `{1}'. An explicit conversion exists (are you missing a cast?)",
313 ec.Report.Error (29, loc, "Cannot implicitly convert type `{0}' to `{1}'",
318 public void Error_TypeArgumentsCannotBeUsed (IMemberContext context, MemberSpec member, Location loc)
320 // Better message for possible generic expressions
321 if (member != null && (member.Kind & MemberKind.GenericMask) != 0) {
322 var report = context.Module.Compiler.Report;
323 report.SymbolRelatedToPreviousError (member);
324 if (member is TypeSpec)
325 member = ((TypeSpec) member).GetDefinition ();
327 member = ((MethodSpec) member).GetGenericMethodDefinition ();
329 string name = member.Kind == MemberKind.Method ? "method" : "type";
330 if (member.IsGeneric) {
331 report.Error (305, loc, "Using the generic {0} `{1}' requires `{2}' type argument(s)",
332 name, member.GetSignatureForError (), member.Arity.ToString ());
334 report.Error (308, loc, "The non-generic {0} `{1}' cannot be used with the type arguments",
335 name, member.GetSignatureForError ());
338 Error_TypeArgumentsCannotBeUsed (context, ExprClassName, GetSignatureForError (), loc);
342 public static void Error_TypeArgumentsCannotBeUsed (IMemberContext context, string exprType, string name, Location loc)
344 context.Module.Compiler.Report.Error (307, loc, "The {0} `{1}' cannot be used with type arguments",
348 public virtual void Error_TypeDoesNotContainDefinition (ResolveContext ec, TypeSpec type, string name)
350 Error_TypeDoesNotContainDefinition (ec, loc, type, name);
353 public static void Error_TypeDoesNotContainDefinition (ResolveContext ec, Location loc, TypeSpec type, string name)
355 ec.Report.SymbolRelatedToPreviousError (type);
356 ec.Report.Error (117, loc, "`{0}' does not contain a definition for `{1}'",
357 type.GetSignatureForError (), name);
360 public virtual void Error_ValueAssignment (ResolveContext rc, Expression rhs)
362 if (rhs == EmptyExpression.LValueMemberAccess || rhs == EmptyExpression.LValueMemberOutAccess) {
363 // Already reported as CS1612
364 } else if (rhs == EmptyExpression.OutAccess) {
365 rc.Report.Error (1510, loc, "A ref or out argument must be an assignable variable");
367 rc.Report.Error (131, loc, "The left-hand side of an assignment must be a variable, a property or an indexer");
371 protected void Error_VoidPointerOperation (ResolveContext rc)
373 rc.Report.Error (242, loc, "The operation in question is undefined on void pointers");
376 public static void Warning_UnreachableExpression (ResolveContext rc, Location loc)
378 rc.Report.Warning (429, 4, loc, "Unreachable expression code detected");
381 public ResolveFlags ExprClassToResolveFlags {
385 case ExprClass.Namespace:
386 return ResolveFlags.Type;
388 case ExprClass.MethodGroup:
389 return ResolveFlags.MethodGroup;
391 case ExprClass.TypeParameter:
392 return ResolveFlags.TypeParameter;
394 case ExprClass.Value:
395 case ExprClass.Variable:
396 case ExprClass.PropertyAccess:
397 case ExprClass.EventAccess:
398 case ExprClass.IndexerAccess:
399 return ResolveFlags.VariableOrValue;
402 throw new InternalErrorException (loc.ToString () + " " + GetType () + " ExprClass is Invalid after resolve");
408 // Implements identical simple name and type-name resolution
410 public Expression ProbeIdenticalTypeName (ResolveContext rc, Expression left, SimpleName name)
413 if (t.Kind == MemberKind.InternalCompilerType || t is ElementTypeSpec || t.Arity > 0)
416 // In a member access of the form E.I, if E is a single identifier, and if the meaning of E as a simple-name is
417 // a constant, field, property, local variable, or parameter with the same type as the meaning of E as a type-name
419 if (left is MemberExpr || left is VariableReference) {
420 var identical_type = rc.LookupNamespaceOrType (name.Name, 0, LookupMode.Probing, loc) as TypeExpr;
421 if (identical_type != null && identical_type.Type == left.Type)
422 return identical_type;
428 public virtual string GetSignatureForError ()
430 return type.GetDefinition ().GetSignatureForError ();
433 public static bool IsNeverNull (Expression expr)
435 if (expr is This || expr is New || expr is ArrayCreation || expr is DelegateCreation || expr is ConditionalMemberAccess)
438 var c = expr as Constant;
442 var tc = expr as TypeCast;
444 return IsNeverNull (tc.Child);
449 protected static bool IsNullPropagatingValid (TypeSpec type)
452 case MemberKind.Struct:
453 return type.IsNullableType;
454 case MemberKind.Enum:
455 case MemberKind.Void:
456 case MemberKind.PointerType:
458 case MemberKind.InternalCompilerType:
459 return type.BuiltinType == BuiltinTypeSpec.Type.Dynamic;
460 case MemberKind.TypeParameter:
461 return !((TypeParameterSpec) type).IsValueType;
467 public virtual bool HasConditionalAccess ()
472 protected TypeSpec LiftMemberType (ResolveContext rc, TypeSpec type)
474 var tps = type as TypeParameterSpec;
475 if (tps != null && !(tps.IsReferenceType || tps.IsValueType)) {
476 Error_OperatorCannotBeApplied (rc, loc, "?", type);
479 return TypeSpec.IsValueType (type) && !type.IsNullableType ?
480 Nullable.NullableInfo.MakeType (rc.Module, type) :
485 /// Resolves an expression and performs semantic analysis on it.
489 /// Currently Resolve wraps DoResolve to perform sanity
490 /// checking and assertion checking on what we expect from Resolve.
492 public Expression Resolve (ResolveContext ec, ResolveFlags flags)
494 if (eclass != ExprClass.Unresolved) {
495 if ((flags & ExprClassToResolveFlags) == 0) {
496 Error_UnexpectedKind (ec, flags, loc);
510 if ((flags & e.ExprClassToResolveFlags) == 0) {
511 e.Error_UnexpectedKind (ec, flags, loc);
516 throw new InternalErrorException ("Expression `{0}' didn't set its type in DoResolve", e.GetType ());
519 } catch (Exception ex) {
520 if (loc.IsNull || ec.Module.Compiler.Settings.BreakOnInternalError || ex is CompletionResult || ec.Report.IsDisabled || ex is FatalException ||
521 ec.Report.Printer is NullReportPrinter)
524 ec.Report.Error (584, loc, "Internal compiler error: {0}", ex.Message);
525 return ErrorExpression.Instance; // TODO: Add location
530 /// Resolves an expression and performs semantic analysis on it.
532 public Expression Resolve (ResolveContext rc)
534 return Resolve (rc, ResolveFlags.VariableOrValue | ResolveFlags.MethodGroup);
538 /// Resolves an expression for LValue assignment
542 /// Currently ResolveLValue wraps DoResolveLValue to perform sanity
543 /// checking and assertion checking on what we expect from Resolve
545 public Expression ResolveLValue (ResolveContext ec, Expression right_side)
547 int errors = ec.Report.Errors;
548 bool out_access = right_side == EmptyExpression.OutAccess;
550 Expression e = DoResolveLValue (ec, right_side);
552 if (e != null && out_access && !(e is IMemoryLocation)) {
553 // FIXME: There's no problem with correctness, the 'Expr = null' handles that.
554 // Enabling this 'throw' will "only" result in deleting useless code elsewhere,
556 //throw new InternalErrorException ("ResolveLValue didn't return an IMemoryLocation: " +
557 // e.GetType () + " " + e.GetSignatureForError ());
562 if (errors == ec.Report.Errors) {
563 Error_ValueAssignment (ec, right_side);
568 if (e.eclass == ExprClass.Unresolved)
569 throw new Exception ("Expression " + e + " ExprClass is Invalid after resolve");
571 if ((e.type == null) && !(e is GenericTypeExpr))
572 throw new Exception ("Expression " + e + " did not set its type after Resolve");
577 public Constant ResolveLabelConstant (ResolveContext rc)
579 var expr = Resolve (rc);
583 Constant c = expr as Constant;
585 if (expr.type != InternalType.ErrorType)
586 rc.Report.Error (150, expr.StartLocation, "A constant value is expected");
594 public virtual void EncodeAttributeValue (IMemberContext rc, AttributeEncoder enc, TypeSpec targetType, TypeSpec parameterType)
596 if (Attribute.IsValidArgumentType (parameterType)) {
597 rc.Module.Compiler.Report.Error (182, loc,
598 "An attribute argument must be a constant expression, typeof expression or array creation expression");
600 rc.Module.Compiler.Report.Error (181, loc,
601 "Attribute constructor parameter has type `{0}', which is not a valid attribute parameter type",
602 targetType.GetSignatureForError ());
607 /// Emits the code for the expression
611 /// The Emit method is invoked to generate the code
612 /// for the expression.
614 public abstract void Emit (EmitContext ec);
617 // Emit code to branch to @target if this expression is equivalent to @on_true.
618 // The default implementation is to emit the value, and then emit a brtrue or brfalse.
619 // Subclasses can provide more efficient implementations, but those MUST be equivalent,
620 // including the use of conditional branches. Note also that a branch MUST be emitted
621 public virtual void EmitBranchable (EmitContext ec, Label target, bool on_true)
624 ec.Emit (on_true ? OpCodes.Brtrue : OpCodes.Brfalse, target);
627 // Emit this expression for its side effects, not for its value.
628 // The default implementation is to emit the value, and then throw it away.
629 // Subclasses can provide more efficient implementations, but those MUST be equivalent
630 public virtual void EmitSideEffect (EmitContext ec)
633 ec.Emit (OpCodes.Pop);
637 // Emits the expression into temporary field variable. The method
638 // should be used for await expressions only
640 public virtual Expression EmitToField (EmitContext ec)
643 // This is the await prepare Emit method. When emitting code like
644 // a + b we emit code like
650 // For await a + await b we have to interfere the flow to keep the
651 // stack clean because await yields from the expression. The emit
654 // a = a.EmitToField () // a is changed to temporary field access
655 // b = b.EmitToField ()
661 // The idea is to emit expression and leave the stack empty with
662 // result value still available.
664 // Expressions should override this default implementation when
665 // optimized version can be provided (e.g. FieldExpr)
668 // We can optimize for side-effect free expressions, they can be
669 // emitted out of order
671 if (IsSideEffectFree)
674 bool needs_temporary = ContainsEmitWithAwait ();
675 if (!needs_temporary)
678 // Emit original code
679 var field = EmitToFieldSource (ec);
682 // Store the result to temporary field when we
683 // cannot load `this' directly
685 field = ec.GetTemporaryField (type);
686 if (needs_temporary) {
688 // Create temporary local (we cannot load `this' before Emit)
690 var temp = ec.GetTemporaryLocal (type);
691 ec.Emit (OpCodes.Stloc, temp);
694 ec.Emit (OpCodes.Ldloc, temp);
695 field.EmitAssignFromStack (ec);
697 ec.FreeTemporaryLocal (temp, type);
699 field.EmitAssignFromStack (ec);
706 protected virtual FieldExpr EmitToFieldSource (EmitContext ec)
709 // Default implementation calls Emit method
715 protected static void EmitExpressionsList (EmitContext ec, List<Expression> expressions)
717 if (ec.HasSet (BuilderContext.Options.AsyncBody)) {
718 bool contains_await = false;
720 for (int i = 1; i < expressions.Count; ++i) {
721 if (expressions[i].ContainsEmitWithAwait ()) {
722 contains_await = true;
727 if (contains_await) {
728 for (int i = 0; i < expressions.Count; ++i) {
729 expressions[i] = expressions[i].EmitToField (ec);
734 for (int i = 0; i < expressions.Count; ++i) {
735 expressions[i].Emit (ec);
740 /// Protected constructor. Only derivate types should
741 /// be able to be created
744 protected Expression ()
749 /// Returns a fully formed expression after a MemberLookup
752 static Expression ExprClassFromMemberInfo (MemberSpec spec, Location loc)
754 if (spec is EventSpec)
755 return new EventExpr ((EventSpec) spec, loc);
756 if (spec is ConstSpec)
757 return new ConstantExpr ((ConstSpec) spec, loc);
758 if (spec is FieldSpec)
759 return new FieldExpr ((FieldSpec) spec, loc);
760 if (spec is PropertySpec)
761 return new PropertyExpr ((PropertySpec) spec, loc);
762 if (spec is TypeSpec)
763 return new TypeExpression (((TypeSpec) spec), loc);
768 public static MethodSpec ConstructorLookup (ResolveContext rc, TypeSpec type, ref Arguments args, Location loc)
770 var ctors = MemberCache.FindMembers (type, Constructor.ConstructorName, true);
773 case MemberKind.Struct:
774 // Every struct has implicit default constructor if not provided by user
778 rc.Report.SymbolRelatedToPreviousError (type);
779 // Report meaningful error for struct as they always have default ctor in C# context
780 OverloadResolver.Error_ConstructorMismatch (rc, type, args == null ? 0 : args.Count, loc);
782 case MemberKind.MissingType:
783 case MemberKind.InternalCompilerType:
784 // LAMESPEC: dynamic is not really object
785 // if (type.BuiltinType == BuiltinTypeSpec.Type.Object)
789 rc.Report.SymbolRelatedToPreviousError (type);
790 rc.Report.Error (143, loc, "The class `{0}' has no constructors defined",
791 type.GetSignatureForError ());
798 if (args == null && type.IsStruct) {
799 bool includes_empty = false;
800 foreach (MethodSpec ctor in ctors) {
801 if (ctor.Parameters.IsEmpty) {
802 includes_empty = true;
810 var r = new OverloadResolver (ctors, OverloadResolver.Restrictions.NoBaseMembers, loc);
811 if (!rc.HasSet (ResolveContext.Options.BaseInitializer)) {
812 r.InstanceQualifier = new ConstructorInstanceQualifier (type);
815 return r.ResolveMember<MethodSpec> (rc, ref args);
819 public enum MemberLookupRestrictions
825 EmptyArguments = 1 << 4,
826 IgnoreArity = 1 << 5,
827 IgnoreAmbiguity = 1 << 6,
828 NameOfExcluded = 1 << 7,
829 DontSetConditionalAccess = 1 << 8
833 // Lookup type `queried_type' for code in class `container_type' with a qualifier of
834 // `qualifier_type' or null to lookup members in the current class.
836 public static Expression MemberLookup (IMemberContext rc, bool errorMode, TypeSpec queried_type, string name, int arity, MemberLookupRestrictions restrictions, Location loc)
838 var members = MemberCache.FindMembers (queried_type, name, false);
844 expr = MemberLookupToExpression (rc, members, errorMode, queried_type, name, arity, restrictions, loc);
848 if (members [0].DeclaringType.BaseType == null)
851 members = MemberCache.FindMembers (members [0].DeclaringType.BaseType, name, false);
852 } while (members != null);
857 public static Expression MemberLookupToExpression (IMemberContext rc, IList<MemberSpec> members, bool errorMode, TypeSpec queried_type, string name, int arity, MemberLookupRestrictions restrictions, Location loc)
859 MemberSpec non_method = null;
860 MemberSpec ambig_non_method = null;
862 for (int i = 0; i < members.Count; ++i) {
863 var member = members [i];
865 // HACK: for events because +=/-= can appear at same class only, should use OverrideToBase there
866 if ((member.Modifiers & Modifiers.OVERRIDE) != 0 && member.Kind != MemberKind.Event)
869 if ((member.Modifiers & Modifiers.BACKING_FIELD) != 0 || member.Kind == MemberKind.Operator)
872 if ((arity > 0 || (restrictions & MemberLookupRestrictions.ExactArity) != 0) && member.Arity != arity)
876 if (!member.IsAccessible (rc))
880 // With runtime binder we can have a situation where queried type is inaccessible
881 // because it came via dynamic object, the check about inconsisted accessibility
882 // had no effect as the type was unknown during compilation
885 // private class N { }
887 // public dynamic Foo ()
893 if (rc.Module.Compiler.IsRuntimeBinder && !member.DeclaringType.IsAccessible (rc))
897 if ((restrictions & MemberLookupRestrictions.InvocableOnly) != 0) {
898 if (member is MethodSpec) {
900 // Interface members that are hidden by class members are removed from the set. This
901 // step only has an effect if T is a type parameter and T has both an effective base
902 // class other than object and a non-empty effective interface set
904 var tps = queried_type as TypeParameterSpec;
905 if (tps != null && tps.HasTypeConstraint)
906 members = RemoveHiddenTypeParameterMethods (members);
908 return new MethodGroupExpr (members, queried_type, loc);
911 if (!Invocation.IsMemberInvocable (member))
915 if (non_method == null || member is MethodSpec || non_method.IsNotCSharpCompatible) {
917 } else if (!errorMode && !member.IsNotCSharpCompatible) {
919 // Interface members that are hidden by class members are removed from the set when T is a type parameter and
920 // T has both an effective base class other than object and a non-empty effective interface set.
922 // The spec has more complex rules but we simply remove all members declared in an interface declaration.
924 var tps = queried_type as TypeParameterSpec;
925 if (tps != null && tps.HasTypeConstraint) {
926 if (non_method.DeclaringType.IsClass && member.DeclaringType.IsInterface)
929 if (non_method.DeclaringType.IsInterface && member.DeclaringType.IsInterface) {
935 ambig_non_method = member;
939 if (non_method != null) {
940 if (ambig_non_method != null && rc != null && (restrictions & MemberLookupRestrictions.IgnoreAmbiguity) == 0) {
941 var report = rc.Module.Compiler.Report;
942 report.SymbolRelatedToPreviousError (non_method);
943 report.SymbolRelatedToPreviousError (ambig_non_method);
944 report.Error (229, loc, "Ambiguity between `{0}' and `{1}'",
945 non_method.GetSignatureForError (), ambig_non_method.GetSignatureForError ());
948 if (non_method is MethodSpec)
949 return new MethodGroupExpr (members, queried_type, loc);
951 return ExprClassFromMemberInfo (non_method, loc);
957 static IList<MemberSpec> RemoveHiddenTypeParameterMethods (IList<MemberSpec> members)
959 if (members.Count < 2)
963 // If M is a method, then all non-method members declared in an interface declaration
964 // are removed from the set, and all methods with the same signature as M declared in
965 // an interface declaration are removed from the set
969 for (int i = 0; i < members.Count; ++i) {
970 var method = members[i] as MethodSpec;
971 if (method == null) {
974 members = new List<MemberSpec> (members);
977 members.RemoveAt (i--);
981 if (!method.DeclaringType.IsInterface)
984 for (int ii = 0; ii < members.Count; ++ii) {
985 var candidate = members[ii] as MethodSpec;
986 if (candidate == null || !candidate.DeclaringType.IsClass)
989 if (!TypeSpecComparer.Override.IsEqual (candidate.Parameters, method.Parameters))
992 if (!AParametersCollection.HasSameParameterDefaults (candidate.Parameters, method.Parameters))
997 members = new List<MemberSpec> (members);
1000 members.RemoveAt (i--);
1008 protected static void Error_NamedArgument (NamedArgument na, Report Report)
1010 Report.Error (1742, na.Location, "An element access expression cannot use named argument");
1013 protected virtual void Error_NegativeArrayIndex (ResolveContext ec, Location loc)
1015 throw new NotImplementedException ();
1018 public virtual void Error_OperatorCannotBeApplied (ResolveContext rc, Location loc, string oper, TypeSpec t)
1020 if (t == InternalType.ErrorType)
1023 rc.Report.Error (23, loc, "The `{0}' operator cannot be applied to operand of type `{1}'",
1024 oper, t.GetSignatureForError ());
1027 protected void Error_PointerInsideExpressionTree (ResolveContext ec)
1029 ec.Report.Error (1944, loc, "An expression tree cannot contain an unsafe pointer operation");
1032 protected void Error_NullShortCircuitInsideExpressionTree (ResolveContext rc)
1034 rc.Report.Error (8072, loc, "An expression tree cannot contain a null propagating operator");
1037 protected void Error_NullPropagatingLValue (ResolveContext rc)
1039 rc.Report.Error (-1030, loc, "The left-hand side of an assignment cannot contain a null propagating operator");
1042 public virtual void FlowAnalysis (FlowAnalysisContext fc)
1047 // Special version of flow analysis for expressions which can return different
1048 // on-true and on-false result. Used by &&, ||, ?: expressions
1050 public virtual void FlowAnalysisConditional (FlowAnalysisContext fc)
1053 fc.DefiniteAssignmentOnTrue = fc.DefiniteAssignmentOnFalse = fc.DefiniteAssignment;
1057 /// Returns an expression that can be used to invoke operator true
1058 /// on the expression if it exists.
1060 protected static Expression GetOperatorTrue (ResolveContext ec, Expression e, Location loc)
1062 return GetOperatorTrueOrFalse (ec, e, true, loc);
1066 /// Returns an expression that can be used to invoke operator false
1067 /// on the expression if it exists.
1069 protected static Expression GetOperatorFalse (ResolveContext ec, Expression e, Location loc)
1071 return GetOperatorTrueOrFalse (ec, e, false, loc);
1074 static Expression GetOperatorTrueOrFalse (ResolveContext ec, Expression e, bool is_true, Location loc)
1076 var op = is_true ? Operator.OpType.True : Operator.OpType.False;
1078 if (type.IsNullableType)
1079 type = Nullable.NullableInfo.GetUnderlyingType (type);
1081 var methods = MemberCache.GetUserOperator (type, op, false);
1082 if (methods == null)
1085 Arguments arguments = new Arguments (1);
1086 arguments.Add (new Argument (e));
1088 var res = new OverloadResolver (methods, OverloadResolver.Restrictions.BaseMembersIncluded | OverloadResolver.Restrictions.NoBaseMembers, loc);
1089 var oper = res.ResolveOperator (ec, ref arguments);
1094 return new UserOperatorCall (oper, arguments, null, loc);
1097 public virtual string ExprClassName
1101 case ExprClass.Unresolved:
1102 return "Unresolved";
1103 case ExprClass.Value:
1105 case ExprClass.Variable:
1107 case ExprClass.Namespace:
1109 case ExprClass.Type:
1111 case ExprClass.MethodGroup:
1112 return "method group";
1113 case ExprClass.PropertyAccess:
1114 return "property access";
1115 case ExprClass.EventAccess:
1116 return "event access";
1117 case ExprClass.IndexerAccess:
1118 return "indexer access";
1119 case ExprClass.Nothing:
1121 case ExprClass.TypeParameter:
1122 return "type parameter";
1124 throw new Exception ("Should not happen");
1129 /// Reports that we were expecting `expr' to be of class `expected'
1131 public static void Error_UnexpectedKind (IMemberContext ctx, Expression memberExpr, string expected, string was, Location loc)
1133 var name = memberExpr.GetSignatureForError ();
1135 ctx.Module.Compiler.Report.Error (118, loc, "`{0}' is a `{1}' but a `{2}' was expected", name, was, expected);
1138 public virtual void Error_UnexpectedKind (ResolveContext ec, ResolveFlags flags, Location loc)
1140 string [] valid = new string [4];
1143 if ((flags & ResolveFlags.VariableOrValue) != 0) {
1144 valid [count++] = "variable";
1145 valid [count++] = "value";
1148 if ((flags & ResolveFlags.Type) != 0)
1149 valid [count++] = "type";
1151 if ((flags & ResolveFlags.MethodGroup) != 0)
1152 valid [count++] = "method group";
1155 valid [count++] = "unknown";
1157 StringBuilder sb = new StringBuilder (valid [0]);
1158 for (int i = 1; i < count - 1; i++) {
1160 sb.Append (valid [i]);
1163 sb.Append ("' or `");
1164 sb.Append (valid [count - 1]);
1167 ec.Report.Error (119, loc,
1168 "Expression denotes a `{0}', where a `{1}' was expected", ExprClassName, sb.ToString ());
1171 public static void UnsafeError (ResolveContext ec, Location loc)
1173 UnsafeError (ec.Report, loc);
1176 public static void UnsafeError (Report Report, Location loc)
1178 Report.Error (214, loc, "Pointers and fixed size buffers may only be used in an unsafe context");
1182 // Converts `source' to an int, uint, long or ulong.
1184 protected Expression ConvertExpressionToArrayIndex (ResolveContext ec, Expression source, bool pointerArray = false)
1186 var btypes = ec.BuiltinTypes;
1188 if (source.type.BuiltinType == BuiltinTypeSpec.Type.Dynamic) {
1189 Arguments args = new Arguments (1);
1190 args.Add (new Argument (source));
1191 return new DynamicConversion (btypes.Int, CSharpBinderFlags.ConvertArrayIndex, args, source.loc).Resolve (ec);
1194 Expression converted;
1196 using (ec.Set (ResolveContext.Options.CheckedScope)) {
1197 converted = Convert.ImplicitConversion (ec, source, btypes.Int, source.loc);
1198 if (converted == null)
1199 converted = Convert.ImplicitConversion (ec, source, btypes.UInt, source.loc);
1200 if (converted == null)
1201 converted = Convert.ImplicitConversion (ec, source, btypes.Long, source.loc);
1202 if (converted == null)
1203 converted = Convert.ImplicitConversion (ec, source, btypes.ULong, source.loc);
1205 if (converted == null) {
1206 source.Error_ValueCannotBeConverted (ec, btypes.Int, false);
1215 // Only positive constants are allowed at compile time
1217 Constant c = converted as Constant;
1218 if (c != null && c.IsNegative)
1219 Error_NegativeArrayIndex (ec, source.loc);
1221 // No conversion needed to array index
1222 if (converted.Type.BuiltinType == BuiltinTypeSpec.Type.Int)
1225 return new ArrayIndexCast (converted, btypes.Int).Resolve (ec);
1228 public Expression MakePointerAccess (ResolveContext rc, TypeSpec type, Arguments args)
1230 if (args.Count != 1){
1231 rc.Report.Error (196, loc, "A pointer must be indexed by only one value");
1236 if (arg is NamedArgument)
1237 Error_NamedArgument ((NamedArgument) arg, rc.Report);
1239 var index = arg.Expr.Resolve (rc);
1243 index = ConvertExpressionToArrayIndex (rc, index, true);
1245 Expression p = new PointerArithmetic (Binary.Operator.Addition, this, index, type, loc);
1246 return new Indirection (p, loc);
1250 // Derived classes implement this method by cloning the fields that
1251 // could become altered during the Resolve stage
1253 // Only expressions that are created for the parser need to implement
1256 protected virtual void CloneTo (CloneContext clonectx, Expression target)
1258 throw new NotImplementedException (
1260 "CloneTo not implemented for expression {0}", this.GetType ()));
1264 // Clones an expression created by the parser.
1266 // We only support expressions created by the parser so far, not
1267 // expressions that have been resolved (many more classes would need
1268 // to implement CloneTo).
1270 // This infrastructure is here merely for Lambda expressions which
1271 // compile the same code using different type values for the same
1272 // arguments to find the correct overload
1274 public virtual Expression Clone (CloneContext clonectx)
1276 Expression cloned = (Expression) MemberwiseClone ();
1277 CloneTo (clonectx, cloned);
1283 // Implementation of expression to expression tree conversion
1285 public abstract Expression CreateExpressionTree (ResolveContext ec);
1287 protected Expression CreateExpressionFactoryCall (ResolveContext ec, string name, Arguments args)
1289 return CreateExpressionFactoryCall (ec, name, null, args, loc);
1292 protected Expression CreateExpressionFactoryCall (ResolveContext ec, string name, TypeArguments typeArguments, Arguments args)
1294 return CreateExpressionFactoryCall (ec, name, typeArguments, args, loc);
1297 public static Expression CreateExpressionFactoryCall (ResolveContext ec, string name, TypeArguments typeArguments, Arguments args, Location loc)
1299 return new Invocation (new MemberAccess (CreateExpressionTypeExpression (ec, loc), name, typeArguments, loc), args);
1302 protected static TypeExpr CreateExpressionTypeExpression (ResolveContext ec, Location loc)
1304 var t = ec.Module.PredefinedTypes.Expression.Resolve ();
1308 return new TypeExpression (t, loc);
1312 // Implemented by all expressions which support conversion from
1313 // compiler expression to invokable runtime expression. Used by
1314 // dynamic C# binder.
1316 public virtual SLE.Expression MakeExpression (BuilderContext ctx)
1318 throw new NotImplementedException ("MakeExpression for " + GetType ());
1321 public virtual object Accept (StructuralVisitor visitor)
1323 return visitor.Visit (this);
1328 /// This is just a base class for expressions that can
1329 /// appear on statements (invocations, object creation,
1330 /// assignments, post/pre increment and decrement). The idea
1331 /// being that they would support an extra Emition interface that
1332 /// does not leave a result on the stack.
1334 public abstract class ExpressionStatement : Expression
1336 public virtual void MarkReachable (Reachability rc)
1340 public virtual ExpressionStatement ResolveStatement (BlockContext ec)
1342 Expression e = Resolve (ec);
1346 ExpressionStatement es = e as ExpressionStatement;
1347 if (es == null || e is AnonymousMethodBody) {
1348 var reduced = e as IReducedExpressionStatement;
1349 if (reduced != null) {
1350 return EmptyExpressionStatement.Instance;
1353 Error_InvalidExpressionStatement (ec);
1357 // This is quite expensive warning, try to limit the damage
1359 if (MemberAccess.IsValidDotExpression (e.Type) && !(e is Assign || e is Await)) {
1360 WarningAsyncWithoutWait (ec, e);
1366 static void WarningAsyncWithoutWait (BlockContext bc, Expression e)
1368 if (bc.CurrentAnonymousMethod is AsyncInitializer) {
1369 var awaiter = new AwaitStatement.AwaitableMemberAccess (e) {
1374 // Need to do full resolve because GetAwaiter can be extension method
1375 // available only in this context
1377 var mg = awaiter.Resolve (bc) as MethodGroupExpr;
1381 var arguments = new Arguments (0);
1382 mg = mg.OverloadResolve (bc, ref arguments, null, OverloadResolver.Restrictions.ProbingOnly);
1387 // Use same check rules as for real await
1389 var awaiter_definition = bc.Module.GetAwaiter (mg.BestCandidateReturnType);
1390 if (!awaiter_definition.IsValidPattern || !awaiter_definition.INotifyCompletion)
1393 bc.Report.Warning (4014, 1, e.Location,
1394 "The statement is not awaited and execution of current method continues before the call is completed. Consider using `await' operator");
1398 var inv = e as Invocation;
1399 if (inv != null && inv.MethodGroup != null && inv.MethodGroup.BestCandidate.IsAsync) {
1400 // The warning won't be reported for imported methods to maintain warning compatiblity with csc
1401 bc.Report.Warning (4014, 1, e.Location,
1402 "The statement is not awaited and execution of current method continues before the call is completed. Consider using `await' operator or calling `Wait' method");
1408 /// Requests the expression to be emitted in a `statement'
1409 /// context. This means that no new value is left on the
1410 /// stack after invoking this method (constrasted with
1411 /// Emit that will always leave a value on the stack).
1413 public abstract void EmitStatement (EmitContext ec);
1415 public override void EmitSideEffect (EmitContext ec)
1421 interface IReducedExpressionStatement
1426 /// This kind of cast is used to encapsulate the child
1427 /// whose type is child.Type into an expression that is
1428 /// reported to return "return_type". This is used to encapsulate
1429 /// expressions which have compatible types, but need to be dealt
1430 /// at higher levels with.
1432 /// For example, a "byte" expression could be encapsulated in one
1433 /// of these as an "unsigned int". The type for the expression
1434 /// would be "unsigned int".
1437 public abstract class TypeCast : Expression
1439 protected readonly Expression child;
1441 protected TypeCast (Expression child, TypeSpec return_type)
1443 eclass = child.eclass;
1444 loc = child.Location;
1449 public Expression Child {
1455 public override bool ContainsEmitWithAwait ()
1457 return child.ContainsEmitWithAwait ();
1460 public override Expression CreateExpressionTree (ResolveContext ec)
1462 Arguments args = new Arguments (2);
1463 args.Add (new Argument (child.CreateExpressionTree (ec)));
1464 args.Add (new Argument (new TypeOf (type, loc)));
1466 if (type.IsPointer || child.Type.IsPointer)
1467 Error_PointerInsideExpressionTree (ec);
1469 return CreateExpressionFactoryCall (ec, ec.HasSet (ResolveContext.Options.CheckedScope) ? "ConvertChecked" : "Convert", args);
1472 protected override Expression DoResolve (ResolveContext ec)
1474 // This should never be invoked, we are born in fully
1475 // initialized state.
1480 public override void Emit (EmitContext ec)
1485 public override void FlowAnalysis (FlowAnalysisContext fc)
1487 child.FlowAnalysis (fc);
1490 public override SLE.Expression MakeExpression (BuilderContext ctx)
1493 return base.MakeExpression (ctx);
1495 return ctx.HasSet (BuilderContext.Options.CheckedScope) ?
1496 SLE.Expression.ConvertChecked (child.MakeExpression (ctx), type.GetMetaInfo ()) :
1497 SLE.Expression.Convert (child.MakeExpression (ctx), type.GetMetaInfo ());
1501 protected override void CloneTo (CloneContext clonectx, Expression t)
1506 public override bool IsNull {
1507 get { return child.IsNull; }
1511 public class EmptyCast : TypeCast {
1512 EmptyCast (Expression child, TypeSpec target_type)
1513 : base (child, target_type)
1517 public static Expression Create (Expression child, TypeSpec type)
1519 Constant c = child as Constant;
1521 var enum_constant = c as EnumConstant;
1522 if (enum_constant != null)
1523 c = enum_constant.Child;
1525 if (!(c is ReducedExpression.ReducedConstantExpression)) {
1529 var res = c.ConvertImplicitly (type);
1535 EmptyCast e = child as EmptyCast;
1537 return new EmptyCast (e.child, type);
1539 return new EmptyCast (child, type);
1542 public override void EmitBranchable (EmitContext ec, Label label, bool on_true)
1544 child.EmitBranchable (ec, label, on_true);
1547 public override void EmitSideEffect (EmitContext ec)
1549 child.EmitSideEffect (ec);
1554 // Used for predefined type user operator (no obsolete check, etc.)
1556 public class OperatorCast : TypeCast
1558 readonly MethodSpec conversion_operator;
1560 public OperatorCast (Expression expr, TypeSpec target_type)
1561 : this (expr, target_type, target_type, false)
1565 public OperatorCast (Expression expr, TypeSpec target_type, bool find_explicit)
1566 : this (expr, target_type, target_type, find_explicit)
1570 public OperatorCast (Expression expr, TypeSpec declaringType, TypeSpec returnType, bool isExplicit)
1571 : base (expr, returnType)
1573 var op = isExplicit ? Operator.OpType.Explicit : Operator.OpType.Implicit;
1574 var mi = MemberCache.GetUserOperator (declaringType, op, true);
1577 foreach (MethodSpec oper in mi) {
1578 if (oper.ReturnType != returnType)
1581 if (oper.Parameters.Types[0] == expr.Type) {
1582 conversion_operator = oper;
1588 throw new InternalErrorException ("Missing predefined user operator between `{0}' and `{1}'",
1589 returnType.GetSignatureForError (), expr.Type.GetSignatureForError ());
1592 public override void Emit (EmitContext ec)
1595 ec.Emit (OpCodes.Call, conversion_operator);
1600 // Constant specialization of EmptyCast.
1601 // We need to special case this since an empty cast of
1602 // a constant is still a constant.
1604 public class EmptyConstantCast : Constant
1606 public readonly Constant child;
1608 public EmptyConstantCast (Constant child, TypeSpec type)
1609 : base (child.Location)
1612 throw new ArgumentNullException ("child");
1615 this.eclass = child.eclass;
1619 public override Constant ConvertExplicitly (bool in_checked_context, TypeSpec target_type)
1621 if (child.Type == target_type)
1624 // FIXME: check that 'type' can be converted to 'target_type' first
1625 return child.ConvertExplicitly (in_checked_context, target_type);
1628 public override Expression CreateExpressionTree (ResolveContext ec)
1630 Arguments args = Arguments.CreateForExpressionTree (ec, null,
1631 child.CreateExpressionTree (ec),
1632 new TypeOf (type, loc));
1635 Error_PointerInsideExpressionTree (ec);
1637 return CreateExpressionFactoryCall (ec, "Convert", args);
1640 public override bool IsDefaultValue {
1641 get { return child.IsDefaultValue; }
1644 public override bool IsNegative {
1645 get { return child.IsNegative; }
1648 public override bool IsNull {
1649 get { return child.IsNull; }
1652 public override bool IsOneInteger {
1653 get { return child.IsOneInteger; }
1656 public override bool IsSideEffectFree {
1658 return child.IsSideEffectFree;
1662 public override bool IsZeroInteger {
1663 get { return child.IsZeroInteger; }
1666 public override void Emit (EmitContext ec)
1671 public override void EmitBranchable (EmitContext ec, Label label, bool on_true)
1673 child.EmitBranchable (ec, label, on_true);
1675 // Only to make verifier happy
1676 if (TypeManager.IsGenericParameter (type) && child.IsNull)
1677 ec.Emit (OpCodes.Unbox_Any, type);
1680 public override void EmitSideEffect (EmitContext ec)
1682 child.EmitSideEffect (ec);
1685 public override object GetValue ()
1687 return child.GetValue ();
1690 public override string GetValueAsLiteral ()
1692 return child.GetValueAsLiteral ();
1695 public override long GetValueAsLong ()
1697 return child.GetValueAsLong ();
1700 public override Constant ConvertImplicitly (TypeSpec target_type)
1702 if (type == target_type)
1705 // FIXME: Do we need to check user conversions?
1706 if (!Convert.ImplicitStandardConversionExists (this, target_type))
1709 return child.ConvertImplicitly (target_type);
1714 /// This class is used to wrap literals which belong inside Enums
1716 public class EnumConstant : Constant
1718 public Constant Child;
1720 public EnumConstant (Constant child, TypeSpec enum_type)
1721 : base (child.Location)
1725 this.eclass = ExprClass.Value;
1726 this.type = enum_type;
1729 protected EnumConstant (Location loc)
1734 public override void Emit (EmitContext ec)
1739 public override void EncodeAttributeValue (IMemberContext rc, AttributeEncoder enc, TypeSpec targetType, TypeSpec parameterType)
1741 Child.EncodeAttributeValue (rc, enc, Child.Type, parameterType);
1744 public override void EmitBranchable (EmitContext ec, Label label, bool on_true)
1746 Child.EmitBranchable (ec, label, on_true);
1749 public override void EmitSideEffect (EmitContext ec)
1751 Child.EmitSideEffect (ec);
1754 public override string GetSignatureForError()
1756 return Type.GetSignatureForError ();
1759 public override object GetValue ()
1761 return Child.GetValue ();
1765 public override object GetTypedValue ()
1768 // The method can be used in dynamic context only (on closed types)
1770 // System.Enum.ToObject cannot be called on dynamic types
1771 // EnumBuilder has to be used, but we cannot use EnumBuilder
1772 // because it does not properly support generics
1774 return System.Enum.ToObject (type.GetMetaInfo (), Child.GetValue ());
1778 public override string GetValueAsLiteral ()
1780 return Child.GetValueAsLiteral ();
1783 public override long GetValueAsLong ()
1785 return Child.GetValueAsLong ();
1788 public EnumConstant Increment()
1790 return new EnumConstant (((IntegralConstant) Child).Increment (), type);
1793 public override bool IsDefaultValue {
1795 return Child.IsDefaultValue;
1799 public override bool IsSideEffectFree {
1801 return Child.IsSideEffectFree;
1805 public override bool IsZeroInteger {
1806 get { return Child.IsZeroInteger; }
1809 public override bool IsNegative {
1811 return Child.IsNegative;
1815 public override Constant ConvertExplicitly (bool in_checked_context, TypeSpec target_type)
1817 if (Child.Type == target_type)
1820 return Child.ConvertExplicitly (in_checked_context, target_type);
1823 public override Constant ConvertImplicitly (TypeSpec type)
1825 if (this.type == type) {
1829 if (!Convert.ImplicitStandardConversionExists (this, type)){
1833 return Child.ConvertImplicitly (type);
1838 /// This kind of cast is used to encapsulate Value Types in objects.
1840 /// The effect of it is to box the value type emitted by the previous
1843 public class BoxedCast : TypeCast {
1845 public BoxedCast (Expression expr, TypeSpec target_type)
1846 : base (expr, target_type)
1848 eclass = ExprClass.Value;
1851 protected override Expression DoResolve (ResolveContext ec)
1853 // This should never be invoked, we are born in fully
1854 // initialized state.
1859 public override void EncodeAttributeValue (IMemberContext rc, AttributeEncoder enc, TypeSpec targetType, TypeSpec parameterType)
1861 // Only boxing to object type is supported
1862 if (targetType.BuiltinType != BuiltinTypeSpec.Type.Object) {
1863 base.EncodeAttributeValue (rc, enc, targetType, parameterType);
1867 enc.Encode (child.Type);
1868 child.EncodeAttributeValue (rc, enc, child.Type, parameterType);
1871 public override void Emit (EmitContext ec)
1875 ec.Emit (OpCodes.Box, child.Type);
1878 public override void EmitSideEffect (EmitContext ec)
1880 // boxing is side-effectful, since it involves runtime checks, except when boxing to Object or ValueType
1881 // so, we need to emit the box+pop instructions in most cases
1882 if (child.Type.IsStruct &&
1883 (type.BuiltinType == BuiltinTypeSpec.Type.Object || type.BuiltinType == BuiltinTypeSpec.Type.ValueType))
1884 child.EmitSideEffect (ec);
1886 base.EmitSideEffect (ec);
1890 public class UnboxCast : TypeCast {
1891 public UnboxCast (Expression expr, TypeSpec return_type)
1892 : base (expr, return_type)
1896 protected override Expression DoResolve (ResolveContext ec)
1898 // This should never be invoked, we are born in fully
1899 // initialized state.
1904 public override void Emit (EmitContext ec)
1908 ec.Emit (OpCodes.Unbox_Any, type);
1913 /// This is used to perform explicit numeric conversions.
1915 /// Explicit numeric conversions might trigger exceptions in a checked
1916 /// context, so they should generate the conv.ovf opcodes instead of
1919 public class ConvCast : TypeCast {
1920 public enum Mode : byte {
1921 I1_U1, I1_U2, I1_U4, I1_U8, I1_CH,
1923 I2_I1, I2_U1, I2_U2, I2_U4, I2_U8, I2_CH,
1924 U2_I1, U2_U1, U2_I2, U2_CH,
1925 I4_I1, I4_U1, I4_I2, I4_U2, I4_U4, I4_U8, I4_CH,
1926 U4_I1, U4_U1, U4_I2, U4_U2, U4_I4, U4_CH,
1927 I8_I1, I8_U1, I8_I2, I8_U2, I8_I4, I8_U4, I8_U8, I8_CH, I8_I,
1928 U8_I1, U8_U1, U8_I2, U8_U2, U8_I4, U8_U4, U8_I8, U8_CH, U8_I,
1929 CH_I1, CH_U1, CH_I2,
1930 R4_I1, R4_U1, R4_I2, R4_U2, R4_I4, R4_U4, R4_I8, R4_U8, R4_CH,
1931 R8_I1, R8_U1, R8_I2, R8_U2, R8_I4, R8_U4, R8_I8, R8_U8, R8_CH, R8_R4,
1937 public ConvCast (Expression child, TypeSpec return_type, Mode m)
1938 : base (child, return_type)
1943 protected override Expression DoResolve (ResolveContext ec)
1945 // This should never be invoked, we are born in fully
1946 // initialized state.
1951 public override string ToString ()
1953 return String.Format ("ConvCast ({0}, {1})", mode, child);
1956 public override void Emit (EmitContext ec)
1962 public static void Emit (EmitContext ec, Mode mode)
1964 if (ec.HasSet (EmitContext.Options.CheckedScope)) {
1966 case Mode.I1_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
1967 case Mode.I1_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1968 case Mode.I1_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
1969 case Mode.I1_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
1970 case Mode.I1_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1972 case Mode.U1_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
1973 case Mode.U1_CH: /* nothing */ break;
1975 case Mode.I2_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
1976 case Mode.I2_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
1977 case Mode.I2_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1978 case Mode.I2_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
1979 case Mode.I2_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
1980 case Mode.I2_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1982 case Mode.U2_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
1983 case Mode.U2_U1: ec.Emit (OpCodes.Conv_Ovf_U1_Un); break;
1984 case Mode.U2_I2: ec.Emit (OpCodes.Conv_Ovf_I2_Un); break;
1985 case Mode.U2_CH: /* nothing */ break;
1987 case Mode.I4_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
1988 case Mode.I4_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
1989 case Mode.I4_I2: ec.Emit (OpCodes.Conv_Ovf_I2); break;
1990 case Mode.I4_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
1991 case Mode.I4_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1992 case Mode.I4_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
1993 case Mode.I4_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1995 case Mode.U4_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
1996 case Mode.U4_U1: ec.Emit (OpCodes.Conv_Ovf_U1_Un); break;
1997 case Mode.U4_I2: ec.Emit (OpCodes.Conv_Ovf_I2_Un); break;
1998 case Mode.U4_U2: ec.Emit (OpCodes.Conv_Ovf_U2_Un); break;
1999 case Mode.U4_I4: ec.Emit (OpCodes.Conv_Ovf_I4_Un); break;
2000 case Mode.U4_CH: ec.Emit (OpCodes.Conv_Ovf_U2_Un); break;
2002 case Mode.I8_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
2003 case Mode.I8_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
2004 case Mode.I8_I2: ec.Emit (OpCodes.Conv_Ovf_I2); break;
2005 case Mode.I8_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
2006 case Mode.I8_I4: ec.Emit (OpCodes.Conv_Ovf_I4); break;
2007 case Mode.I8_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
2008 case Mode.I8_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
2009 case Mode.I8_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
2010 case Mode.I8_I: ec.Emit (OpCodes.Conv_Ovf_U); break;
2012 case Mode.U8_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
2013 case Mode.U8_U1: ec.Emit (OpCodes.Conv_Ovf_U1_Un); break;
2014 case Mode.U8_I2: ec.Emit (OpCodes.Conv_Ovf_I2_Un); break;
2015 case Mode.U8_U2: ec.Emit (OpCodes.Conv_Ovf_U2_Un); break;
2016 case Mode.U8_I4: ec.Emit (OpCodes.Conv_Ovf_I4_Un); break;
2017 case Mode.U8_U4: ec.Emit (OpCodes.Conv_Ovf_U4_Un); break;
2018 case Mode.U8_I8: ec.Emit (OpCodes.Conv_Ovf_I8_Un); break;
2019 case Mode.U8_CH: ec.Emit (OpCodes.Conv_Ovf_U2_Un); break;
2020 case Mode.U8_I: ec.Emit (OpCodes.Conv_Ovf_U_Un); break;
2022 case Mode.CH_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
2023 case Mode.CH_U1: ec.Emit (OpCodes.Conv_Ovf_U1_Un); break;
2024 case Mode.CH_I2: ec.Emit (OpCodes.Conv_Ovf_I2_Un); break;
2026 case Mode.R4_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
2027 case Mode.R4_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
2028 case Mode.R4_I2: ec.Emit (OpCodes.Conv_Ovf_I2); break;
2029 case Mode.R4_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
2030 case Mode.R4_I4: ec.Emit (OpCodes.Conv_Ovf_I4); break;
2031 case Mode.R4_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
2032 case Mode.R4_I8: ec.Emit (OpCodes.Conv_Ovf_I8); break;
2033 case Mode.R4_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
2034 case Mode.R4_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
2036 case Mode.R8_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
2037 case Mode.R8_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
2038 case Mode.R8_I2: ec.Emit (OpCodes.Conv_Ovf_I2); break;
2039 case Mode.R8_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
2040 case Mode.R8_I4: ec.Emit (OpCodes.Conv_Ovf_I4); break;
2041 case Mode.R8_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
2042 case Mode.R8_I8: ec.Emit (OpCodes.Conv_Ovf_I8); break;
2043 case Mode.R8_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
2044 case Mode.R8_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
2045 case Mode.R8_R4: ec.Emit (OpCodes.Conv_R4); break;
2047 case Mode.I_I8: ec.Emit (OpCodes.Conv_Ovf_I8_Un); break;
2051 case Mode.I1_U1: ec.Emit (OpCodes.Conv_U1); break;
2052 case Mode.I1_U2: ec.Emit (OpCodes.Conv_U2); break;
2053 case Mode.I1_U4: ec.Emit (OpCodes.Conv_U4); break;
2054 case Mode.I1_U8: ec.Emit (OpCodes.Conv_I8); break;
2055 case Mode.I1_CH: ec.Emit (OpCodes.Conv_U2); break;
2057 case Mode.U1_I1: ec.Emit (OpCodes.Conv_I1); break;
2058 case Mode.U1_CH: ec.Emit (OpCodes.Conv_U2); break;
2060 case Mode.I2_I1: ec.Emit (OpCodes.Conv_I1); break;
2061 case Mode.I2_U1: ec.Emit (OpCodes.Conv_U1); break;
2062 case Mode.I2_U2: ec.Emit (OpCodes.Conv_U2); break;
2063 case Mode.I2_U4: ec.Emit (OpCodes.Conv_U4); break;
2064 case Mode.I2_U8: ec.Emit (OpCodes.Conv_I8); break;
2065 case Mode.I2_CH: ec.Emit (OpCodes.Conv_U2); break;
2067 case Mode.U2_I1: ec.Emit (OpCodes.Conv_I1); break;
2068 case Mode.U2_U1: ec.Emit (OpCodes.Conv_U1); break;
2069 case Mode.U2_I2: ec.Emit (OpCodes.Conv_I2); break;
2070 case Mode.U2_CH: /* nothing */ break;
2072 case Mode.I4_I1: ec.Emit (OpCodes.Conv_I1); break;
2073 case Mode.I4_U1: ec.Emit (OpCodes.Conv_U1); break;
2074 case Mode.I4_I2: ec.Emit (OpCodes.Conv_I2); break;
2075 case Mode.I4_U4: /* nothing */ break;
2076 case Mode.I4_U2: ec.Emit (OpCodes.Conv_U2); break;
2077 case Mode.I4_U8: ec.Emit (OpCodes.Conv_I8); break;
2078 case Mode.I4_CH: ec.Emit (OpCodes.Conv_U2); break;
2080 case Mode.U4_I1: ec.Emit (OpCodes.Conv_I1); break;
2081 case Mode.U4_U1: ec.Emit (OpCodes.Conv_U1); break;
2082 case Mode.U4_I2: ec.Emit (OpCodes.Conv_I2); break;
2083 case Mode.U4_U2: ec.Emit (OpCodes.Conv_U2); break;
2084 case Mode.U4_I4: /* nothing */ break;
2085 case Mode.U4_CH: ec.Emit (OpCodes.Conv_U2); break;
2087 case Mode.I8_I1: ec.Emit (OpCodes.Conv_I1); break;
2088 case Mode.I8_U1: ec.Emit (OpCodes.Conv_U1); break;
2089 case Mode.I8_I2: ec.Emit (OpCodes.Conv_I2); break;
2090 case Mode.I8_U2: ec.Emit (OpCodes.Conv_U2); break;
2091 case Mode.I8_I4: ec.Emit (OpCodes.Conv_I4); break;
2092 case Mode.I8_U4: ec.Emit (OpCodes.Conv_U4); break;
2093 case Mode.I8_U8: /* nothing */ break;
2094 case Mode.I8_CH: ec.Emit (OpCodes.Conv_U2); break;
2095 case Mode.I8_I: ec.Emit (OpCodes.Conv_U); break;
2097 case Mode.U8_I1: ec.Emit (OpCodes.Conv_I1); break;
2098 case Mode.U8_U1: ec.Emit (OpCodes.Conv_U1); break;
2099 case Mode.U8_I2: ec.Emit (OpCodes.Conv_I2); break;
2100 case Mode.U8_U2: ec.Emit (OpCodes.Conv_U2); break;
2101 case Mode.U8_I4: ec.Emit (OpCodes.Conv_I4); break;
2102 case Mode.U8_U4: ec.Emit (OpCodes.Conv_U4); break;
2103 case Mode.U8_I8: /* nothing */ break;
2104 case Mode.U8_CH: ec.Emit (OpCodes.Conv_U2); break;
2105 case Mode.U8_I: ec.Emit (OpCodes.Conv_U); break;
2107 case Mode.CH_I1: ec.Emit (OpCodes.Conv_I1); break;
2108 case Mode.CH_U1: ec.Emit (OpCodes.Conv_U1); break;
2109 case Mode.CH_I2: ec.Emit (OpCodes.Conv_I2); break;
2111 case Mode.R4_I1: ec.Emit (OpCodes.Conv_I1); break;
2112 case Mode.R4_U1: ec.Emit (OpCodes.Conv_U1); break;
2113 case Mode.R4_I2: ec.Emit (OpCodes.Conv_I2); break;
2114 case Mode.R4_U2: ec.Emit (OpCodes.Conv_U2); break;
2115 case Mode.R4_I4: ec.Emit (OpCodes.Conv_I4); break;
2116 case Mode.R4_U4: ec.Emit (OpCodes.Conv_U4); break;
2117 case Mode.R4_I8: ec.Emit (OpCodes.Conv_I8); break;
2118 case Mode.R4_U8: ec.Emit (OpCodes.Conv_U8); break;
2119 case Mode.R4_CH: ec.Emit (OpCodes.Conv_U2); break;
2121 case Mode.R8_I1: ec.Emit (OpCodes.Conv_I1); break;
2122 case Mode.R8_U1: ec.Emit (OpCodes.Conv_U1); break;
2123 case Mode.R8_I2: ec.Emit (OpCodes.Conv_I2); break;
2124 case Mode.R8_U2: ec.Emit (OpCodes.Conv_U2); break;
2125 case Mode.R8_I4: ec.Emit (OpCodes.Conv_I4); break;
2126 case Mode.R8_U4: ec.Emit (OpCodes.Conv_U4); break;
2127 case Mode.R8_I8: ec.Emit (OpCodes.Conv_I8); break;
2128 case Mode.R8_U8: ec.Emit (OpCodes.Conv_U8); break;
2129 case Mode.R8_CH: ec.Emit (OpCodes.Conv_U2); break;
2130 case Mode.R8_R4: ec.Emit (OpCodes.Conv_R4); break;
2132 case Mode.I_I8: ec.Emit (OpCodes.Conv_U8); break;
2138 class OpcodeCast : TypeCast
2142 public OpcodeCast (Expression child, TypeSpec return_type, OpCode op)
2143 : base (child, return_type)
2148 protected override Expression DoResolve (ResolveContext ec)
2150 // This should never be invoked, we are born in fully
2151 // initialized state.
2156 public override void Emit (EmitContext ec)
2162 public TypeSpec UnderlyingType {
2163 get { return child.Type; }
2168 // Opcode casts expression with 2 opcodes but only
2169 // single expression tree node
2171 class OpcodeCastDuplex : OpcodeCast
2173 readonly OpCode second;
2175 public OpcodeCastDuplex (Expression child, TypeSpec returnType, OpCode first, OpCode second)
2176 : base (child, returnType, first)
2178 this.second = second;
2181 public override void Emit (EmitContext ec)
2189 /// This kind of cast is used to encapsulate a child and cast it
2190 /// to the class requested
2192 public sealed class ClassCast : TypeCast {
2193 readonly bool forced;
2195 public ClassCast (Expression child, TypeSpec return_type)
2196 : base (child, return_type)
2200 public ClassCast (Expression child, TypeSpec return_type, bool forced)
2201 : base (child, return_type)
2203 this.forced = forced;
2206 public override void Emit (EmitContext ec)
2210 bool gen = TypeManager.IsGenericParameter (child.Type);
2212 ec.Emit (OpCodes.Box, child.Type);
2214 if (type.IsGenericParameter) {
2215 ec.Emit (OpCodes.Unbox_Any, type);
2222 ec.Emit (OpCodes.Castclass, type);
2227 // Created during resolving pahse when an expression is wrapped or constantified
2228 // and original expression can be used later (e.g. for expression trees)
2230 public class ReducedExpression : Expression
2232 public class ReducedConstantExpression : EmptyConstantCast
2234 readonly Expression orig_expr;
2236 public ReducedConstantExpression (Constant expr, Expression orig_expr)
2237 : base (expr, expr.Type)
2239 this.orig_expr = orig_expr;
2242 public Expression OriginalExpression {
2248 public override Constant ConvertImplicitly (TypeSpec target_type)
2250 Constant c = base.ConvertImplicitly (target_type);
2252 c = new ReducedConstantExpression (c, orig_expr);
2257 public override Expression CreateExpressionTree (ResolveContext ec)
2259 return orig_expr.CreateExpressionTree (ec);
2262 public override Constant ConvertExplicitly (bool in_checked_context, TypeSpec target_type)
2264 Constant c = base.ConvertExplicitly (in_checked_context, target_type);
2266 c = new ReducedConstantExpression (c, orig_expr);
2270 public override void EncodeAttributeValue (IMemberContext rc, AttributeEncoder enc, TypeSpec targetType, TypeSpec parameterType)
2273 // LAMESPEC: Reduced conditional expression is allowed as an attribute argument
2275 if (orig_expr is Conditional)
2276 child.EncodeAttributeValue (rc, enc, targetType,parameterType);
2278 base.EncodeAttributeValue (rc, enc, targetType, parameterType);
2282 sealed class ReducedConstantStatement : ReducedConstantExpression, IReducedExpressionStatement
2284 public ReducedConstantStatement (Constant expr, Expression origExpr)
2285 : base (expr, origExpr)
2290 sealed class ReducedExpressionStatement : ExpressionStatement
2292 readonly Expression orig_expr;
2293 readonly ExpressionStatement stm;
2295 public ReducedExpressionStatement (ExpressionStatement stm, Expression orig)
2297 this.orig_expr = orig;
2299 this.eclass = stm.eclass;
2300 this.type = stm.Type;
2302 this.loc = orig.Location;
2305 public override bool ContainsEmitWithAwait ()
2307 return stm.ContainsEmitWithAwait ();
2310 public override Expression CreateExpressionTree (ResolveContext ec)
2312 return orig_expr.CreateExpressionTree (ec);
2315 protected override Expression DoResolve (ResolveContext ec)
2320 public override void Emit (EmitContext ec)
2325 public override void EmitStatement (EmitContext ec)
2327 stm.EmitStatement (ec);
2330 public override void FlowAnalysis (FlowAnalysisContext fc)
2332 stm.FlowAnalysis (fc);
2336 readonly Expression expr, orig_expr;
2338 private ReducedExpression (Expression expr, Expression orig_expr)
2341 this.eclass = expr.eclass;
2342 this.type = expr.Type;
2343 this.orig_expr = orig_expr;
2344 this.loc = orig_expr.Location;
2349 public override bool IsSideEffectFree {
2351 return expr.IsSideEffectFree;
2355 public Expression OriginalExpression {
2363 public override bool ContainsEmitWithAwait ()
2365 return expr.ContainsEmitWithAwait ();
2369 // Creates fully resolved expression switcher
2371 public static Constant Create (Constant expr, Expression originalExpr)
2373 if (expr.eclass == ExprClass.Unresolved)
2374 throw new ArgumentException ("Unresolved expression");
2376 if (originalExpr is ExpressionStatement)
2377 return new ReducedConstantStatement (expr, originalExpr);
2379 return new ReducedConstantExpression (expr, originalExpr);
2382 public static ExpressionStatement Create (ExpressionStatement s, Expression orig)
2384 return new ReducedExpressionStatement (s, orig);
2387 public static Expression Create (Expression expr, Expression original_expr)
2389 return Create (expr, original_expr, true);
2393 // Creates unresolved reduce expression. The original expression has to be
2394 // already resolved. Created expression is constant based based on `expr'
2395 // value unless canBeConstant is used
2397 public static Expression Create (Expression expr, Expression original_expr, bool canBeConstant)
2399 if (canBeConstant) {
2400 Constant c = expr as Constant;
2402 return Create (c, original_expr);
2405 ExpressionStatement s = expr as ExpressionStatement;
2407 return Create (s, original_expr);
2409 if (expr.eclass == ExprClass.Unresolved)
2410 throw new ArgumentException ("Unresolved expression");
2412 return new ReducedExpression (expr, original_expr);
2415 public override Expression CreateExpressionTree (ResolveContext ec)
2417 return orig_expr.CreateExpressionTree (ec);
2420 protected override Expression DoResolve (ResolveContext ec)
2425 public override void Emit (EmitContext ec)
2430 public override Expression EmitToField (EmitContext ec)
2432 return expr.EmitToField(ec);
2435 public override void EmitBranchable (EmitContext ec, Label target, bool on_true)
2437 expr.EmitBranchable (ec, target, on_true);
2440 public override void FlowAnalysis (FlowAnalysisContext fc)
2442 expr.FlowAnalysis (fc);
2445 public override SLE.Expression MakeExpression (BuilderContext ctx)
2447 return orig_expr.MakeExpression (ctx);
2452 // Standard composite pattern
2454 public abstract class CompositeExpression : Expression
2456 protected Expression expr;
2458 protected CompositeExpression (Expression expr)
2461 this.loc = expr.Location;
2464 public override bool ContainsEmitWithAwait ()
2466 return expr.ContainsEmitWithAwait ();
2469 public override Expression CreateExpressionTree (ResolveContext rc)
2471 return expr.CreateExpressionTree (rc);
2474 public Expression Child {
2475 get { return expr; }
2478 protected override Expression DoResolve (ResolveContext rc)
2480 expr = expr.Resolve (rc);
2485 eclass = expr.eclass;
2489 public override void Emit (EmitContext ec)
2494 public override bool IsNull {
2495 get { return expr.IsNull; }
2500 // Base of expressions used only to narrow resolve flow
2502 public abstract class ShimExpression : Expression
2504 protected Expression expr;
2506 protected ShimExpression (Expression expr)
2511 public Expression Expr {
2517 protected override void CloneTo (CloneContext clonectx, Expression t)
2522 ShimExpression target = (ShimExpression) t;
2523 target.expr = expr.Clone (clonectx);
2526 public override bool ContainsEmitWithAwait ()
2528 return expr.ContainsEmitWithAwait ();
2531 public override Expression CreateExpressionTree (ResolveContext ec)
2533 throw new NotSupportedException ("ET");
2536 public override void Emit (EmitContext ec)
2538 throw new InternalErrorException ("Missing Resolve call");
2542 public class UnreachableExpression : Expression
2544 public UnreachableExpression (Expression expr)
2546 this.loc = expr.Location;
2549 public override Expression CreateExpressionTree (ResolveContext ec)
2552 throw new NotImplementedException ();
2555 protected override Expression DoResolve (ResolveContext rc)
2557 throw new NotSupportedException ();
2560 public override void FlowAnalysis (FlowAnalysisContext fc)
2562 fc.Report.Warning (429, 4, loc, "Unreachable expression code detected");
2565 public override void Emit (EmitContext ec)
2569 public override void EmitBranchable (EmitContext ec, Label target, bool on_true)
2575 // Unresolved type name expressions
2577 public abstract class ATypeNameExpression : FullNamedExpression
2580 protected TypeArguments targs;
2582 protected ATypeNameExpression (string name, Location l)
2588 protected ATypeNameExpression (string name, TypeArguments targs, Location l)
2595 protected ATypeNameExpression (string name, int arity, Location l)
2596 : this (name, new UnboundTypeArguments (arity, l), l)
2604 return targs == null ? 0 : targs.Count;
2608 public bool HasTypeArguments {
2610 return targs != null && !targs.IsEmpty;
2614 public string Name {
2623 public TypeArguments TypeArguments {
2631 public override bool Equals (object obj)
2633 ATypeNameExpression atne = obj as ATypeNameExpression;
2634 return atne != null && atne.Name == Name &&
2635 (targs == null || targs.Equals (atne.targs));
2638 public override int GetHashCode ()
2640 return Name.GetHashCode ();
2643 // TODO: Move it to MemberCore
2644 public static string GetMemberType (MemberCore mc)
2650 if (mc is FieldBase)
2652 if (mc is MethodCore)
2654 if (mc is EnumMember)
2662 public override string GetSignatureForError ()
2664 if (targs != null) {
2665 return Name + "<" + targs.GetSignatureForError () + ">";
2671 public abstract Expression LookupNameExpression (ResolveContext rc, MemberLookupRestrictions restriction);
2675 /// SimpleName expressions are formed of a single word and only happen at the beginning
2676 /// of a dotted-name.
2678 public class SimpleName : ATypeNameExpression
2680 public SimpleName (string name, Location l)
2685 public SimpleName (string name, TypeArguments args, Location l)
2686 : base (name, args, l)
2690 public SimpleName (string name, int arity, Location l)
2691 : base (name, arity, l)
2695 public SimpleName GetMethodGroup ()
2697 return new SimpleName (Name, targs, loc);
2700 protected override Expression DoResolve (ResolveContext rc)
2702 return SimpleNameResolve (rc, null);
2705 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
2707 return SimpleNameResolve (ec, right_side);
2710 public void Error_NameDoesNotExist (ResolveContext rc)
2712 rc.Report.Error (103, loc, "The name `{0}' does not exist in the current context", Name);
2715 protected virtual void Error_TypeOrNamespaceNotFound (IMemberContext ctx)
2717 if (ctx.CurrentType != null) {
2718 var member = MemberLookup (ctx, false, ctx.CurrentType, Name, 0, MemberLookupRestrictions.ExactArity, loc) as MemberExpr;
2719 if (member != null) {
2720 Error_UnexpectedKind (ctx, member, "type", member.KindName, loc);
2725 var report = ctx.Module.Compiler.Report;
2727 var retval = ctx.LookupNamespaceOrType (Name, Arity, LookupMode.IgnoreAccessibility, loc);
2728 if (retval != null) {
2729 report.SymbolRelatedToPreviousError (retval.Type);
2730 ErrorIsInaccesible (ctx, retval.GetSignatureForError (), loc);
2734 retval = ctx.LookupNamespaceOrType (Name, -System.Math.Max (1, Arity), LookupMode.Probing, loc);
2735 if (retval != null) {
2736 Error_TypeArgumentsCannotBeUsed (ctx, retval.Type, loc);
2740 var ns_candidates = ctx.Module.GlobalRootNamespace.FindTypeNamespaces (ctx, Name, Arity);
2741 if (ns_candidates != null) {
2742 if (ctx is UsingAliasNamespace.AliasContext) {
2743 report.Error (246, loc,
2744 "The type or namespace name `{1}' could not be found. Consider using fully qualified name `{0}.{1}'",
2745 ns_candidates[0], Name);
2747 string usings = string.Join ("' or `", ns_candidates.ToArray ());
2748 report.Error (246, loc,
2749 "The type or namespace name `{0}' could not be found. Are you missing `{1}' using directive?",
2753 report.Error (246, loc,
2754 "The type or namespace name `{0}' could not be found. Are you missing an assembly reference?",
2759 public override FullNamedExpression ResolveAsTypeOrNamespace (IMemberContext mc, bool allowUnboundTypeArguments)
2761 FullNamedExpression fne = mc.LookupNamespaceOrType (Name, Arity, LookupMode.Normal, loc);
2764 if (fne.Type != null && Arity > 0) {
2765 if (HasTypeArguments) {
2766 GenericTypeExpr ct = new GenericTypeExpr (fne.Type, targs, loc);
2767 if (ct.ResolveAsType (mc) == null)
2773 targs.Resolve (mc, allowUnboundTypeArguments);
2775 return new GenericOpenTypeExpr (fne.Type, loc);
2779 // dynamic namespace is ignored when dynamic is allowed (does not apply to types)
2781 if (!(fne is NamespaceExpression))
2785 if (Arity == 0 && Name == "dynamic" && !(mc is NamespaceContainer) && mc.Module.Compiler.Settings.Version > LanguageVersion.V_3) {
2786 if (!mc.Module.PredefinedAttributes.Dynamic.IsDefined) {
2787 mc.Module.Compiler.Report.Error (1980, Location,
2788 "Dynamic keyword requires `{0}' to be defined. Are you missing System.Core.dll assembly reference?",
2789 mc.Module.PredefinedAttributes.Dynamic.GetSignatureForError ());
2792 fne = new DynamicTypeExpr (loc);
2793 fne.ResolveAsType (mc);
2799 Error_TypeOrNamespaceNotFound (mc);
2803 public bool IsPossibleTypeOrNamespace (IMemberContext mc)
2805 return mc.LookupNamespaceOrType (Name, Arity, LookupMode.Probing, loc) != null;
2808 public bool IsPossibleType (IMemberContext mc)
2810 return mc.LookupNamespaceOrType (Name, Arity, LookupMode.Probing, loc) is TypeExpr;
2813 public override Expression LookupNameExpression (ResolveContext rc, MemberLookupRestrictions restrictions)
2815 int lookup_arity = Arity;
2816 bool errorMode = false;
2818 Block current_block = rc.CurrentBlock;
2819 INamedBlockVariable variable = null;
2820 bool variable_found = false;
2824 // Stage 1: binding to local variables or parameters
2826 // LAMESPEC: It should take invocableOnly into account but that would break csc compatibility
2828 if (current_block != null && lookup_arity == 0) {
2829 if (current_block.ParametersBlock.TopBlock.GetLocalName (Name, current_block.Original, ref variable)) {
2830 if (!variable.IsDeclared) {
2831 // We found local name in accessible block but it's not
2832 // initialized yet, maybe the user wanted to bind to something else
2834 variable_found = true;
2836 e = variable.CreateReferenceExpression (rc, loc);
2839 Error_TypeArgumentsCannotBeUsed (rc, "variable", Name, loc);
2848 // Stage 2: Lookup members if we are inside a type up to top level type for nested types
2850 TypeSpec member_type = rc.CurrentType;
2851 for (; member_type != null; member_type = member_type.DeclaringType) {
2852 e = MemberLookup (rc, errorMode, member_type, Name, lookup_arity, restrictions, loc);
2856 var me = e as MemberExpr;
2858 // The name matches a type, defer to ResolveAsTypeStep
2866 if (variable != null) {
2867 if (me is FieldExpr || me is ConstantExpr || me is EventExpr || me is PropertyExpr) {
2868 rc.Report.Error (844, loc,
2869 "A local variable `{0}' cannot be used before it is declared. Consider renaming the local variable when it hides the member `{1}'",
2870 Name, me.GetSignatureForError ());
2874 } else if (me is MethodGroupExpr || me is PropertyExpr || me is IndexerExpr) {
2875 // Leave it to overload resolution to report correct error
2877 // TODO: rc.Report.SymbolRelatedToPreviousError ()
2878 ErrorIsInaccesible (rc, me.GetSignatureForError (), loc);
2882 // MemberLookup does not check accessors availability, this is actually needed for properties only
2884 var pe = me as PropertyExpr;
2887 // Break as there is no other overload available anyway
2888 if ((restrictions & MemberLookupRestrictions.ReadAccess) != 0) {
2889 if (!pe.PropertyInfo.HasGet || !pe.PropertyInfo.Get.IsAccessible (rc))
2892 pe.Getter = pe.PropertyInfo.Get;
2894 if (!pe.PropertyInfo.HasSet) {
2895 if (rc.HasSet (ResolveContext.Options.ConstructorScope) && pe.IsAutoPropertyAccess &&
2896 pe.PropertyInfo.DeclaringType == rc.CurrentType && pe.IsStatic == rc.IsStatic) {
2897 var p = (Property) pe.PropertyInfo.MemberDefinition;
2898 return new FieldExpr (p.BackingField, loc);
2901 variable_found = true;
2905 if (!pe.PropertyInfo.Set.IsAccessible (rc)) {
2906 variable_found = true;
2910 pe.Setter = pe.PropertyInfo.Set;
2915 // TODO: It's used by EventExpr -> FieldExpr transformation only
2916 // TODO: Should go to MemberAccess
2917 me = me.ResolveMemberAccess (rc, null, null);
2920 targs.Resolve (rc, false);
2921 me.SetTypeArguments (rc, targs);
2928 // Stage 3: Lookup nested types, namespaces and type parameters in the context
2930 if ((restrictions & MemberLookupRestrictions.InvocableOnly) == 0 && !variable_found) {
2931 if (IsPossibleTypeOrNamespace (rc)) {
2932 return ResolveAsTypeOrNamespace (rc, false);
2936 var expr = NamespaceContainer.LookupStaticUsings (rc, Name, Arity, loc);
2939 targs.Resolve (rc, false);
2941 var me = expr as MemberExpr;
2943 me.SetTypeArguments (rc, targs);
2948 if ((restrictions & MemberLookupRestrictions.NameOfExcluded) == 0 && Name == "nameof")
2949 return new NameOf (this);
2952 if (variable_found) {
2953 rc.Report.Error (841, loc, "A local variable `{0}' cannot be used before it is declared", Name);
2956 var tparams = rc.CurrentTypeParameters;
2957 if (tparams != null) {
2958 if (tparams.Find (Name) != null) {
2959 Error_TypeArgumentsCannotBeUsed (rc, "type parameter", Name, loc);
2964 var ct = rc.CurrentType;
2966 if (ct.MemberDefinition.TypeParametersCount > 0) {
2967 foreach (var ctp in ct.MemberDefinition.TypeParameters) {
2968 if (ctp.Name == Name) {
2969 Error_TypeArgumentsCannotBeUsed (rc, "type parameter", Name, loc);
2975 ct = ct.DeclaringType;
2976 } while (ct != null);
2979 if ((restrictions & MemberLookupRestrictions.InvocableOnly) == 0) {
2980 e = rc.LookupNamespaceOrType (Name, Arity, LookupMode.IgnoreAccessibility, loc);
2982 rc.Report.SymbolRelatedToPreviousError (e.Type);
2983 ErrorIsInaccesible (rc, e.GetSignatureForError (), loc);
2987 var me = MemberLookup (rc, false, rc.CurrentType, Name, Arity, restrictions & ~MemberLookupRestrictions.InvocableOnly, loc) as MemberExpr;
2989 Error_UnexpectedKind (rc, me, "method group", me.KindName, loc);
2990 return ErrorExpression.Instance;
2994 e = rc.LookupNamespaceOrType (Name, -System.Math.Max (1, Arity), LookupMode.Probing, loc);
2996 if (e.Type.Arity != Arity && (restrictions & MemberLookupRestrictions.IgnoreArity) == 0) {
2997 Error_TypeArgumentsCannotBeUsed (rc, e.Type, loc);
3001 if (e is TypeExpr) {
3002 // TypeExpression does not have correct location
3003 if (e is TypeExpression)
3004 e = new TypeExpression (e.Type, loc);
3010 Error_NameDoesNotExist (rc);
3013 return ErrorExpression.Instance;
3016 if (rc.Module.Evaluator != null) {
3017 var fi = rc.Module.Evaluator.LookupField (Name);
3019 return new FieldExpr (fi.Item1, loc);
3027 Expression SimpleNameResolve (ResolveContext ec, Expression right_side)
3029 Expression e = LookupNameExpression (ec, right_side == null ? MemberLookupRestrictions.ReadAccess : MemberLookupRestrictions.None);
3034 if (e is FullNamedExpression && e.eclass != ExprClass.Unresolved) {
3035 Error_UnexpectedKind (ec, e, "variable", e.ExprClassName, loc);
3039 if (right_side != null) {
3040 e = e.ResolveLValue (ec, right_side);
3048 public override object Accept (StructuralVisitor visitor)
3050 return visitor.Visit (this);
3055 /// Represents a namespace or a type. The name of the class was inspired by
3056 /// section 10.8.1 (Fully Qualified Names).
3058 public abstract class FullNamedExpression : Expression
3060 protected override void CloneTo (CloneContext clonectx, Expression target)
3062 // Do nothing, most unresolved type expressions cannot be
3063 // resolved to different type
3066 public override bool ContainsEmitWithAwait ()
3071 public override Expression CreateExpressionTree (ResolveContext ec)
3073 throw new NotSupportedException ("ET");
3076 public abstract FullNamedExpression ResolveAsTypeOrNamespace (IMemberContext mc, bool allowUnboundTypeArguments);
3079 // This is used to resolve the expression as a type, a null
3080 // value will be returned if the expression is not a type
3083 public override TypeSpec ResolveAsType (IMemberContext mc, bool allowUnboundTypeArguments = false)
3085 FullNamedExpression fne = ResolveAsTypeOrNamespace (mc, allowUnboundTypeArguments);
3090 TypeExpr te = fne as TypeExpr;
3092 Error_UnexpectedKind (mc, fne, "type", fne.ExprClassName, loc);
3100 var dep = type.GetMissingDependencies ();
3102 ImportedTypeDefinition.Error_MissingDependency (mc, dep, loc);
3105 if (type.Kind == MemberKind.Void) {
3106 mc.Module.Compiler.Report.Error (673, loc, "System.Void cannot be used from C#. Consider using `void'");
3110 // Obsolete checks cannot be done when resolving base context as they
3111 // require type dependencies to be set but we are in process of resolving them
3113 if (mc is ResolveContext) {
3114 var oa = type.GetAttributeObsolete ();
3115 if (oa != null && !mc.IsObsolete)
3116 AttributeTester.Report_ObsoleteMessage (oa, type.GetSignatureForError (), fne.Location, mc.Module.Compiler.Report);
3123 public override void Emit (EmitContext ec)
3125 throw new InternalErrorException ("FullNamedExpression `{0}' found in resolved tree",
3126 GetSignatureForError ());
3131 /// Expression that evaluates to a type
3133 public abstract class TypeExpr : FullNamedExpression
3135 public sealed override FullNamedExpression ResolveAsTypeOrNamespace (IMemberContext mc, bool allowUnboundTypeArguments)
3141 protected sealed override Expression DoResolve (ResolveContext ec)
3147 public override bool Equals (object obj)
3149 TypeExpr tobj = obj as TypeExpr;
3153 return Type == tobj.Type;
3156 public override int GetHashCode ()
3158 return Type.GetHashCode ();
3163 /// Fully resolved Expression that already evaluated to a type
3165 public class TypeExpression : TypeExpr
3167 public TypeExpression (TypeSpec t, Location l)
3170 eclass = ExprClass.Type;
3174 public sealed override TypeSpec ResolveAsType (IMemberContext mc, bool allowUnboundTypeArguments = false)
3180 public class NamespaceExpression : FullNamedExpression
3182 readonly Namespace ns;
3184 public NamespaceExpression (Namespace ns, Location loc)
3187 this.Type = InternalType.Namespace;
3188 this.eclass = ExprClass.Namespace;
3192 public Namespace Namespace {
3198 protected override Expression DoResolve (ResolveContext rc)
3200 throw new NotImplementedException ();
3203 public override FullNamedExpression ResolveAsTypeOrNamespace (IMemberContext mc, bool allowUnboundTypeArguments)
3208 public void Error_NamespaceDoesNotExist (IMemberContext ctx, string name, int arity, Location loc)
3210 var retval = Namespace.LookupType (ctx, name, arity, LookupMode.IgnoreAccessibility, loc);
3211 if (retval != null) {
3212 // ctx.Module.Compiler.Report.SymbolRelatedToPreviousError (retval.MemberDefinition);
3213 ErrorIsInaccesible (ctx, retval.GetSignatureForError (), loc);
3217 retval = Namespace.LookupType (ctx, name, -System.Math.Max (1, arity), LookupMode.Probing, loc);
3218 if (retval != null) {
3219 Error_TypeArgumentsCannotBeUsed (ctx, retval, loc);
3224 if (arity > 0 && Namespace.TryGetNamespace (name, out ns)) {
3225 Error_TypeArgumentsCannotBeUsed (ctx, ExprClassName, ns.GetSignatureForError (), loc);
3229 string assembly = null;
3230 string possible_name = Namespace.GetSignatureForError () + "." + name;
3232 // Only assembly unique name should be added
3233 switch (possible_name) {
3234 case "System.Drawing":
3235 case "System.Web.Services":
3238 case "System.Configuration":
3239 case "System.Data.Services":
3240 case "System.DirectoryServices":
3242 case "System.Net.Http":
3243 case "System.Numerics":
3244 case "System.Runtime.Caching":
3245 case "System.ServiceModel":
3246 case "System.Transactions":
3247 case "System.Web.Routing":
3248 case "System.Xml.Linq":
3250 assembly = possible_name;
3254 case "System.Linq.Expressions":
3255 assembly = "System.Core";
3258 case "System.Windows.Forms":
3259 case "System.Windows.Forms.Layout":
3260 assembly = "System.Windows.Forms";
3264 assembly = assembly == null ? "an" : "`" + assembly + "'";
3266 if (Namespace is GlobalRootNamespace) {
3267 ctx.Module.Compiler.Report.Error (400, loc,
3268 "The type or namespace name `{0}' could not be found in the global namespace. Are you missing {1} assembly reference?",
3271 ctx.Module.Compiler.Report.Error (234, loc,
3272 "The type or namespace name `{0}' does not exist in the namespace `{1}'. Are you missing {2} assembly reference?",
3273 name, GetSignatureForError (), assembly);
3277 public override string GetSignatureForError ()
3279 return ns.GetSignatureForError ();
3282 public FullNamedExpression LookupTypeOrNamespace (IMemberContext ctx, string name, int arity, LookupMode mode, Location loc)
3284 return ns.LookupTypeOrNamespace (ctx, name, arity, mode, loc);
3287 public override string ToString ()
3289 return Namespace.Name;
3294 /// This class denotes an expression which evaluates to a member
3295 /// of a struct or a class.
3297 public abstract class MemberExpr : Expression, OverloadResolver.IInstanceQualifier
3299 protected bool conditional_access_receiver;
3302 // An instance expression associated with this member, if it's a
3303 // non-static member
3305 public Expression InstanceExpression;
3308 /// The name of this member.
3310 public abstract string Name {
3315 // When base.member is used
3317 public bool IsBase {
3318 get { return InstanceExpression is BaseThis; }
3322 /// Whether this is an instance member.
3324 public abstract bool IsInstance {
3329 /// Whether this is a static member.
3331 public abstract bool IsStatic {
3335 public abstract string KindName {
3339 public bool ConditionalAccess { get; set; }
3341 protected abstract TypeSpec DeclaringType {
3345 TypeSpec OverloadResolver.IInstanceQualifier.InstanceType {
3347 return InstanceExpression.Type;
3352 // Converts best base candidate for virtual method starting from QueriedBaseType
3354 protected MethodSpec CandidateToBaseOverride (ResolveContext rc, MethodSpec method)
3357 // Only when base.member is used and method is virtual
3363 // Overload resulution works on virtual or non-virtual members only (no overrides). That
3364 // means for base.member access we have to find the closest match after we found best candidate
3366 if ((method.Modifiers & (Modifiers.ABSTRACT | Modifiers.VIRTUAL | Modifiers.OVERRIDE)) != 0) {
3368 // The method could already be what we are looking for
3370 TypeSpec[] targs = null;
3371 if (method.DeclaringType != InstanceExpression.Type) {
3373 // Candidate can have inflated MVAR parameters and we need to find
3374 // base match for original definition not inflated parameter types
3376 var parameters = method.Parameters;
3377 if (method.Arity > 0) {
3378 parameters = ((IParametersMember) method.MemberDefinition).Parameters;
3379 var inflated = method.DeclaringType as InflatedTypeSpec;
3380 if (inflated != null) {
3381 parameters = parameters.Inflate (inflated.CreateLocalInflator (rc));
3385 var filter = new MemberFilter (method.Name, method.Arity, MemberKind.Method, parameters, null);
3386 var base_override = MemberCache.FindMember (InstanceExpression.Type, filter, BindingRestriction.InstanceOnly | BindingRestriction.OverrideOnly) as MethodSpec;
3387 if (base_override != null && base_override.DeclaringType != method.DeclaringType) {
3388 if (base_override.IsGeneric)
3389 targs = method.TypeArguments;
3391 method = base_override;
3396 // When base access is used inside anonymous method/iterator/etc we need to
3397 // get back to the context of original type. We do it by emiting proxy
3398 // method in original class and rewriting base call to this compiler
3399 // generated method call which does the actual base invocation. This may
3400 // introduce redundant storey but with `this' only but it's tricky to avoid
3401 // at this stage as we don't know what expressions follow base
3403 if (rc.CurrentAnonymousMethod != null) {
3404 if (targs == null && method.IsGeneric) {
3405 targs = method.TypeArguments;
3406 method = method.GetGenericMethodDefinition ();
3409 if (method.Parameters.HasArglist)
3410 throw new NotImplementedException ("__arglist base call proxy");
3412 method = rc.CurrentMemberDefinition.Parent.PartialContainer.CreateHoistedBaseCallProxy (rc, method);
3414 // Ideally this should apply to any proxy rewrite but in the case of unary mutators on
3415 // get/set member expressions second call would fail to proxy because left expression
3416 // would be of 'this' and not 'base' because we share InstanceExpression for get/set
3417 // FIXME: The async check is another hack but will probably fail with mutators
3418 if (rc.CurrentType.IsStruct || rc.CurrentAnonymousMethod.Storey is AsyncTaskStorey)
3419 InstanceExpression = new This (loc).Resolve (rc);
3423 method = method.MakeGenericMethod (rc, targs);
3427 // Only base will allow this invocation to happen.
3429 if (method.IsAbstract) {
3430 rc.Report.SymbolRelatedToPreviousError (method);
3431 Error_CannotCallAbstractBase (rc, method.GetSignatureForError ());
3437 protected void CheckProtectedMemberAccess (ResolveContext rc, MemberSpec member)
3439 if (InstanceExpression == null)
3442 if ((member.Modifiers & Modifiers.PROTECTED) != 0 && !(InstanceExpression is This)) {
3443 if (!CheckProtectedMemberAccess (rc, member, InstanceExpression.Type)) {
3444 Error_ProtectedMemberAccess (rc, member, InstanceExpression.Type, loc);
3449 bool OverloadResolver.IInstanceQualifier.CheckProtectedMemberAccess (ResolveContext rc, MemberSpec member)
3451 if (InstanceExpression == null)
3454 return InstanceExpression is This || CheckProtectedMemberAccess (rc, member, InstanceExpression.Type);
3457 public static bool CheckProtectedMemberAccess<T> (ResolveContext rc, T member, TypeSpec qualifier) where T : MemberSpec
3459 var ct = rc.CurrentType;
3460 if (ct == qualifier)
3463 if ((member.Modifiers & Modifiers.INTERNAL) != 0 && member.DeclaringType.MemberDefinition.IsInternalAsPublic (ct.MemberDefinition.DeclaringAssembly))
3466 qualifier = qualifier.GetDefinition ();
3467 if (ct != qualifier && !IsSameOrBaseQualifier (ct, qualifier)) {
3474 public override bool ContainsEmitWithAwait ()
3476 return InstanceExpression != null && InstanceExpression.ContainsEmitWithAwait ();
3479 public override bool HasConditionalAccess ()
3481 return ConditionalAccess || (InstanceExpression != null && InstanceExpression.HasConditionalAccess ());
3484 static bool IsSameOrBaseQualifier (TypeSpec type, TypeSpec qtype)
3487 type = type.GetDefinition ();
3489 if (type == qtype || TypeManager.IsFamilyAccessible (qtype, type))
3492 type = type.DeclaringType;
3493 } while (type != null);
3498 protected void DoBestMemberChecks<T> (ResolveContext rc, T member) where T : MemberSpec, IInterfaceMemberSpec
3500 if (InstanceExpression != null) {
3501 InstanceExpression = InstanceExpression.Resolve (rc);
3502 CheckProtectedMemberAccess (rc, member);
3505 if (member.MemberType.IsPointer && !rc.IsUnsafe) {
3506 UnsafeError (rc, loc);
3509 var dep = member.GetMissingDependencies ();
3511 ImportedTypeDefinition.Error_MissingDependency (rc, dep, loc);
3514 member.CheckObsoleteness (rc, loc);
3516 if (!(member is FieldSpec))
3517 member.MemberDefinition.SetIsUsed ();
3520 protected virtual void Error_CannotCallAbstractBase (ResolveContext rc, string name)
3522 rc.Report.Error (205, loc, "Cannot call an abstract base member `{0}'", name);
3525 public static void Error_ProtectedMemberAccess (ResolveContext rc, MemberSpec member, TypeSpec qualifier, Location loc)
3527 rc.Report.SymbolRelatedToPreviousError (member);
3528 rc.Report.Error (1540, loc,
3529 "Cannot access protected member `{0}' via a qualifier of type `{1}'. The qualifier must be of type `{2}' or derived from it",
3530 member.GetSignatureForError (), qualifier.GetSignatureForError (), rc.CurrentType.GetSignatureForError ());
3533 public override void FlowAnalysis (FlowAnalysisContext fc)
3535 if (InstanceExpression != null) {
3536 InstanceExpression.FlowAnalysis (fc);
3540 protected void ResolveConditionalAccessReceiver (ResolveContext rc)
3542 if (!rc.HasSet (ResolveContext.Options.DontSetConditionalAccessReceiver) && HasConditionalAccess ()) {
3543 conditional_access_receiver = true;
3547 public bool ResolveInstanceExpression (ResolveContext rc, Expression rhs)
3549 if (!ResolveInstanceExpressionCore (rc, rhs))
3553 // Check intermediate value modification which won't have any effect
3555 if (rhs != null && TypeSpec.IsValueType (InstanceExpression.Type)) {
3556 var fexpr = InstanceExpression as FieldExpr;
3557 if (fexpr != null) {
3558 if (!fexpr.Spec.IsReadOnly || rc.HasAny (ResolveContext.Options.FieldInitializerScope | ResolveContext.Options.ConstructorScope))
3561 if (fexpr.IsStatic) {
3562 rc.Report.Error (1650, loc, "Fields of static readonly field `{0}' cannot be assigned to (except in a static constructor or a variable initializer)",
3563 fexpr.GetSignatureForError ());
3565 rc.Report.Error (1648, loc, "Members of readonly field `{0}' cannot be modified (except in a constructor or a variable initializer)",
3566 fexpr.GetSignatureForError ());
3572 if (InstanceExpression is PropertyExpr || InstanceExpression is IndexerExpr || InstanceExpression is Invocation) {
3573 if (rc.CurrentInitializerVariable != null) {
3574 rc.Report.Error (1918, loc, "Members of value type `{0}' cannot be assigned using a property `{1}' object initializer",
3575 InstanceExpression.Type.GetSignatureForError (), InstanceExpression.GetSignatureForError ());
3577 rc.Report.Error (1612, loc,
3578 "Cannot modify a value type return value of `{0}'. Consider storing the value in a temporary variable",
3579 InstanceExpression.GetSignatureForError ());
3585 var lvr = InstanceExpression as LocalVariableReference;
3588 if (!lvr.local_info.IsReadonly)
3591 rc.Report.Error (1654, loc, "Cannot assign to members of `{0}' because it is a `{1}'",
3592 InstanceExpression.GetSignatureForError (), lvr.local_info.GetReadOnlyContext ());
3599 bool ResolveInstanceExpressionCore (ResolveContext rc, Expression rhs)
3602 if (InstanceExpression != null) {
3603 if (InstanceExpression is TypeExpr) {
3604 var t = InstanceExpression.Type;
3606 t.CheckObsoleteness (rc, loc);
3608 t = t.DeclaringType;
3609 } while (t != null);
3611 var runtime_expr = InstanceExpression as RuntimeValueExpression;
3612 if (runtime_expr == null || !runtime_expr.IsSuggestionOnly) {
3613 rc.Report.Error (176, loc,
3614 "Static member `{0}' cannot be accessed with an instance reference, qualify it with a type name instead",
3615 GetSignatureForError ());
3619 InstanceExpression = null;
3625 if (InstanceExpression == null || InstanceExpression is TypeExpr) {
3626 if (InstanceExpression != null || !This.IsThisAvailable (rc, true)) {
3627 if (rc.HasSet (ResolveContext.Options.FieldInitializerScope)) {
3628 rc.Report.Error (236, loc,
3629 "A field initializer cannot reference the nonstatic field, method, or property `{0}'",
3630 GetSignatureForError ());
3632 var fe = this as FieldExpr;
3633 if (fe != null && fe.Spec.MemberDefinition is PrimaryConstructorField) {
3634 if (rc.HasSet (ResolveContext.Options.BaseInitializer)) {
3635 rc.Report.Error (9005, loc, "Constructor initializer cannot access primary constructor parameters");
3637 rc.Report.Error (9006, loc, "An object reference is required to access primary constructor parameter `{0}'",
3641 rc.Report.Error (120, loc,
3642 "An object reference is required to access non-static member `{0}'",
3643 GetSignatureForError ());
3647 InstanceExpression = new CompilerGeneratedThis (rc.CurrentType, loc).Resolve (rc);
3651 if (!TypeManager.IsFamilyAccessible (rc.CurrentType, DeclaringType)) {
3652 rc.Report.Error (38, loc,
3653 "Cannot access a nonstatic member of outer type `{0}' via nested type `{1}'",
3654 DeclaringType.GetSignatureForError (), rc.CurrentType.GetSignatureForError ());
3657 InstanceExpression = new This (loc).Resolve (rc);
3661 var me = InstanceExpression as MemberExpr;
3663 me.ResolveInstanceExpressionCore (rc, rhs);
3665 var fe = me as FieldExpr;
3666 if (fe != null && fe.IsMarshalByRefAccess (rc)) {
3667 rc.Report.SymbolRelatedToPreviousError (me.DeclaringType);
3668 rc.Report.Warning (1690, 1, loc,
3669 "Cannot call methods, properties, or indexers on `{0}' because it is a value type member of a marshal-by-reference class",
3670 me.GetSignatureForError ());
3677 // Additional checks for l-value member access
3680 if (InstanceExpression is UnboxCast) {
3681 rc.Report.Error (445, InstanceExpression.Location, "Cannot modify the result of an unboxing conversion");
3688 public virtual MemberExpr ResolveMemberAccess (ResolveContext ec, Expression left, SimpleName original)
3690 if (left != null && !ConditionalAccess && !ec.HasSet (ResolveContext.Options.NameOfScope) && left.IsNull && TypeSpec.IsReferenceType (left.Type)) {
3691 ec.Report.Warning (1720, 1, left.Location,
3692 "Expression will always cause a `{0}'", "System.NullReferenceException");
3695 InstanceExpression = left;
3699 protected void EmitInstance (EmitContext ec, bool prepare_for_load)
3701 var inst = new InstanceEmitter (InstanceExpression, TypeSpec.IsValueType (InstanceExpression.Type));
3702 inst.Emit (ec, ConditionalAccess);
3704 if (prepare_for_load)
3705 ec.Emit (OpCodes.Dup);
3708 public abstract void SetTypeArguments (ResolveContext ec, TypeArguments ta);
3711 public class ExtensionMethodCandidates
3713 readonly NamespaceContainer container;
3714 readonly IList<MethodSpec> methods;
3716 readonly IMemberContext context;
3718 public ExtensionMethodCandidates (IMemberContext context, IList<MethodSpec> methods, NamespaceContainer nsContainer, int lookupIndex)
3720 this.context = context;
3721 this.methods = methods;
3722 this.container = nsContainer;
3723 this.index = lookupIndex;
3726 public NamespaceContainer Container {
3732 public IMemberContext Context {
3738 public int LookupIndex {
3744 public IList<MethodSpec> Methods {
3752 // Represents a group of extension method candidates for whole namespace
3754 class ExtensionMethodGroupExpr : MethodGroupExpr, OverloadResolver.IErrorHandler
3756 ExtensionMethodCandidates candidates;
3757 public Expression ExtensionExpression;
3759 public ExtensionMethodGroupExpr (ExtensionMethodCandidates candidates, Expression extensionExpr, Location loc)
3760 : base (candidates.Methods.Cast<MemberSpec>().ToList (), extensionExpr.Type, loc)
3762 this.candidates = candidates;
3763 this.ExtensionExpression = extensionExpr;
3766 public override bool IsStatic {
3767 get { return true; }
3771 // For extension methodgroup we are not looking for base members but parent
3772 // namespace extension methods
3774 public override IList<MemberSpec> GetBaseMembers (TypeSpec baseType)
3776 // TODO: candidates are null only when doing error reporting, that's
3777 // incorrect. We have to discover same extension methods in error mode
3778 if (candidates == null)
3781 int arity = type_arguments == null ? 0 : type_arguments.Count;
3783 candidates = candidates.Container.LookupExtensionMethod (candidates.Context, Name, arity, candidates.LookupIndex);
3784 if (candidates == null)
3787 return candidates.Methods.Cast<MemberSpec> ().ToList ();
3790 public static bool IsExtensionTypeCompatible (TypeSpec argType, TypeSpec extensionType)
3793 // Indentity, implicit reference or boxing conversion must exist for the extension parameter
3795 // LAMESPEC: or implicit type parameter conversion
3797 return argType == extensionType ||
3798 TypeSpecComparer.IsEqual (argType, extensionType) ||
3799 Convert.ImplicitReferenceConversionExists (argType, extensionType, false) ||
3800 Convert.ImplicitBoxingConversion (null, argType, extensionType) != null;
3803 public bool ResolveNameOf (ResolveContext rc, MemberAccess ma)
3805 rc.Report.Error (8093, ma.Location, "An argument to nameof operator cannot be extension method group");
3807 // Not included in C#6
3809 ExtensionExpression = ExtensionExpression.Resolve (rc);
3810 if (ExtensionExpression == null)
3813 var argType = ExtensionExpression.Type;
3814 foreach (MethodSpec candidate in Candidates) {
3815 if (ExtensionMethodGroupExpr.IsExtensionTypeCompatible (argType, candidate.Parameters.ExtensionMethodType))
3819 // TODO: Scan full hierarchy
3821 ma.Error_TypeDoesNotContainDefinition (rc, argType, ma.Name);
3826 public override MethodGroupExpr LookupExtensionMethod (ResolveContext rc)
3828 // We are already here
3832 public override MethodGroupExpr OverloadResolve (ResolveContext ec, ref Arguments arguments, OverloadResolver.IErrorHandler ehandler, OverloadResolver.Restrictions restr)
3834 if (arguments == null)
3835 arguments = new Arguments (1);
3837 ExtensionExpression = ExtensionExpression.Resolve (ec);
3838 if (ExtensionExpression == null)
3841 var cand = candidates;
3842 var atype = ConditionalAccess ? Argument.AType.ExtensionTypeConditionalAccess : Argument.AType.ExtensionType;
3843 arguments.Insert (0, new Argument (ExtensionExpression, atype));
3844 var res = base.OverloadResolve (ec, ref arguments, ehandler ?? this, restr);
3846 // Restore candidates in case we are running in probing mode
3849 // Store resolved argument and restore original arguments
3851 // Clean-up modified arguments for error reporting
3852 arguments.RemoveAt (0);
3856 var me = ExtensionExpression as MemberExpr;
3858 me.ResolveInstanceExpression (ec, null);
3859 var fe = me as FieldExpr;
3861 fe.Spec.MemberDefinition.SetIsUsed ();
3864 InstanceExpression = null;
3868 #region IErrorHandler Members
3870 bool OverloadResolver.IErrorHandler.AmbiguousCandidates (ResolveContext rc, MemberSpec best, MemberSpec ambiguous)
3875 bool OverloadResolver.IErrorHandler.ArgumentMismatch (ResolveContext rc, MemberSpec best, Argument arg, int index)
3877 rc.Report.SymbolRelatedToPreviousError (best);
3880 rc.Report.Error (1929, loc,
3881 "Type `{0}' does not contain a member `{1}' and the best extension method overload `{2}' requires an instance of type `{3}'",
3882 queried_type.GetSignatureForError (), Name, best.GetSignatureForError (), ((MethodSpec)best).Parameters.ExtensionMethodType.GetSignatureForError ());
3884 rc.Report.Error (1928, loc,
3885 "Type `{0}' does not contain a member `{1}' and the best extension method overload `{2}' has some invalid arguments",
3886 queried_type.GetSignatureForError (), Name, best.GetSignatureForError ());
3892 bool OverloadResolver.IErrorHandler.NoArgumentMatch (ResolveContext rc, MemberSpec best)
3897 bool OverloadResolver.IErrorHandler.TypeInferenceFailed (ResolveContext rc, MemberSpec best)
3906 /// MethodGroupExpr represents a group of method candidates which
3907 /// can be resolved to the best method overload
3909 public class MethodGroupExpr : MemberExpr, OverloadResolver.IBaseMembersProvider
3911 static readonly MemberSpec[] Excluded = new MemberSpec[0];
3913 protected IList<MemberSpec> Methods;
3914 MethodSpec best_candidate;
3915 TypeSpec best_candidate_return;
3916 protected TypeArguments type_arguments;
3918 SimpleName simple_name;
3919 protected TypeSpec queried_type;
3921 public MethodGroupExpr (IList<MemberSpec> mi, TypeSpec type, Location loc)
3925 this.type = InternalType.MethodGroup;
3927 eclass = ExprClass.MethodGroup;
3928 queried_type = type;
3931 public MethodGroupExpr (MethodSpec m, TypeSpec type, Location loc)
3932 : this (new MemberSpec[] { m }, type, loc)
3938 public MethodSpec BestCandidate {
3940 return best_candidate;
3944 public TypeSpec BestCandidateReturnType {
3946 return best_candidate_return;
3950 public IList<MemberSpec> Candidates {
3956 protected override TypeSpec DeclaringType {
3958 return queried_type;
3962 public bool IsConditionallyExcluded {
3964 return Methods == Excluded;
3968 public override bool IsInstance {
3970 if (best_candidate != null)
3971 return !best_candidate.IsStatic;
3977 public override bool IsSideEffectFree {
3979 return InstanceExpression == null || InstanceExpression.IsSideEffectFree;
3983 public override bool IsStatic {
3985 if (best_candidate != null)
3986 return best_candidate.IsStatic;
3992 public override string KindName {
3993 get { return "method"; }
3996 public override string Name {
3998 if (best_candidate != null)
3999 return best_candidate.Name;
4002 return Methods.First ().Name;
4009 // When best candidate is already know this factory can be used
4010 // to avoid expensive overload resolution to be called
4012 // NOTE: InstanceExpression has to be set manually
4014 public static MethodGroupExpr CreatePredefined (MethodSpec best, TypeSpec queriedType, Location loc)
4016 return new MethodGroupExpr (best, queriedType, loc) {
4017 best_candidate = best,
4018 best_candidate_return = best.ReturnType
4022 public override string GetSignatureForError ()
4024 if (best_candidate != null)
4025 return best_candidate.GetSignatureForError ();
4027 return Methods.First ().GetSignatureForError ();
4030 public override Expression CreateExpressionTree (ResolveContext ec)
4032 if (best_candidate == null) {
4033 ec.Report.Error (1953, loc, "An expression tree cannot contain an expression with method group");
4037 if (IsConditionallyExcluded)
4038 ec.Report.Error (765, loc,
4039 "Partial methods with only a defining declaration or removed conditional methods cannot be used in an expression tree");
4041 if (ConditionalAccess)
4042 Error_NullShortCircuitInsideExpressionTree (ec);
4044 return new TypeOfMethod (best_candidate, loc);
4047 protected override Expression DoResolve (ResolveContext ec)
4049 this.eclass = ExprClass.MethodGroup;
4051 if (InstanceExpression != null) {
4052 InstanceExpression = InstanceExpression.Resolve (ec);
4053 if (InstanceExpression == null)
4060 public override void Emit (EmitContext ec)
4062 throw new NotSupportedException ();
4065 public void EmitCall (EmitContext ec, Arguments arguments, bool statement)
4067 var call = new CallEmitter ();
4068 call.InstanceExpression = InstanceExpression;
4069 call.ConditionalAccess = ConditionalAccess;
4072 call.EmitStatement (ec, best_candidate, arguments, loc);
4074 call.Emit (ec, best_candidate, arguments, loc);
4077 public void EmitCall (EmitContext ec, Arguments arguments, TypeSpec conditionalAccessReceiver, bool statement)
4079 var ca = ec.ConditionalAccess;
4080 ec.ConditionalAccess = new ConditionalAccessContext (conditionalAccessReceiver, ec.DefineLabel ()) {
4081 Statement = statement
4084 EmitCall (ec, arguments, statement);
4086 ec.CloseConditionalAccess (!statement && best_candidate_return != conditionalAccessReceiver && conditionalAccessReceiver.IsNullableType ? conditionalAccessReceiver : null);
4087 ec.ConditionalAccess = ca;
4090 public override void Error_ValueCannotBeConverted (ResolveContext ec, TypeSpec target, bool expl)
4092 if (target != InternalType.ErrorType) {
4093 ec.Report.Error (428, loc, "Cannot convert method group `{0}' to non-delegate type `{1}'. Consider using parentheses to invoke the method",
4094 Name, target.GetSignatureForError ());
4098 public bool HasAccessibleCandidate (ResolveContext rc)
4100 foreach (var candidate in Candidates) {
4101 if (candidate.IsAccessible (rc))
4108 public static bool IsExtensionMethodArgument (Expression expr)
4111 // LAMESPEC: No details about which expressions are not allowed
4113 return !(expr is TypeExpr) && !(expr is BaseThis);
4117 /// Find the Applicable Function Members (7.4.2.1)
4119 /// me: Method Group expression with the members to select.
4120 /// it might contain constructors or methods (or anything
4121 /// that maps to a method).
4123 /// Arguments: ArrayList containing resolved Argument objects.
4125 /// loc: The location if we want an error to be reported, or a Null
4126 /// location for "probing" purposes.
4128 /// Returns: The MethodBase (either a ConstructorInfo or a MethodInfo)
4129 /// that is the best match of me on Arguments.
4132 public virtual MethodGroupExpr OverloadResolve (ResolveContext ec, ref Arguments args, OverloadResolver.IErrorHandler cerrors, OverloadResolver.Restrictions restr)
4134 // TODO: causes issues with probing mode, remove explicit Kind check
4135 if (best_candidate != null && best_candidate.Kind == MemberKind.Destructor)
4138 var r = new OverloadResolver (Methods, type_arguments, restr, loc);
4139 if ((restr & OverloadResolver.Restrictions.NoBaseMembers) == 0) {
4140 r.BaseMembersProvider = this;
4141 r.InstanceQualifier = this;
4144 if (cerrors != null)
4145 r.CustomErrors = cerrors;
4147 // TODO: When in probing mode do IsApplicable only and when called again do VerifyArguments for full error reporting
4148 best_candidate = r.ResolveMember<MethodSpec> (ec, ref args);
4149 if (best_candidate == null) {
4150 if (!r.BestCandidateIsDynamic)
4153 if (simple_name != null && ec.IsStatic)
4154 InstanceExpression = ProbeIdenticalTypeName (ec, InstanceExpression, simple_name);
4159 // Overload resolver had to create a new method group, all checks bellow have already been executed
4160 if (r.BestCandidateNewMethodGroup != null)
4161 return r.BestCandidateNewMethodGroup;
4163 if (best_candidate.Kind == MemberKind.Method && (restr & OverloadResolver.Restrictions.ProbingOnly) == 0) {
4164 if (InstanceExpression != null) {
4165 if (best_candidate.IsExtensionMethod && args[0].Expr == InstanceExpression) {
4166 InstanceExpression = null;
4168 if (simple_name != null && best_candidate.IsStatic) {
4169 InstanceExpression = ProbeIdenticalTypeName (ec, InstanceExpression, simple_name);
4172 InstanceExpression.Resolve (ec, ResolveFlags.VariableOrValue | ResolveFlags.MethodGroup | ResolveFlags.Type);
4176 ResolveInstanceExpression (ec, null);
4179 var base_override = CandidateToBaseOverride (ec, best_candidate);
4180 if (base_override == best_candidate) {
4181 best_candidate_return = r.BestCandidateReturnType;
4183 best_candidate = base_override;
4184 best_candidate_return = best_candidate.ReturnType;
4187 if (best_candidate.IsGeneric && (restr & OverloadResolver.Restrictions.ProbingOnly) == 0 && TypeParameterSpec.HasAnyTypeParameterConstrained (best_candidate.GenericDefinition)) {
4188 ConstraintChecker cc = new ConstraintChecker (ec);
4189 cc.CheckAll (best_candidate.GetGenericMethodDefinition (), best_candidate.TypeArguments, best_candidate.Constraints, loc);
4193 // Additional check for possible imported base override method which
4194 // could not be done during IsOverrideMethodBaseTypeAccessible
4196 if (best_candidate.IsVirtual && (best_candidate.DeclaringType.Modifiers & Modifiers.PROTECTED) != 0 &&
4197 best_candidate.MemberDefinition.IsImported && !best_candidate.DeclaringType.IsAccessible (ec)) {
4198 ec.Report.SymbolRelatedToPreviousError (best_candidate);
4199 ErrorIsInaccesible (ec, best_candidate.GetSignatureForError (), loc);
4202 // Speed up the check by not doing it on disallowed targets
4203 if (best_candidate_return.Kind == MemberKind.Void && best_candidate.IsConditionallyExcluded (ec))
4209 public override MemberExpr ResolveMemberAccess (ResolveContext ec, Expression left, SimpleName original)
4211 var fe = left as FieldExpr;
4214 // Using method-group on struct fields makes the struct assigned. I am not sure
4215 // why but that's what .net does
4217 fe.Spec.MemberDefinition.SetIsAssigned ();
4220 simple_name = original;
4221 return base.ResolveMemberAccess (ec, left, original);
4224 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
4226 type_arguments = ta;
4229 #region IBaseMembersProvider Members
4231 public virtual IList<MemberSpec> GetBaseMembers (TypeSpec baseType)
4233 return baseType == null ? null : MemberCache.FindMembers (baseType, Methods [0].Name, false);
4236 public IParametersMember GetOverrideMemberParameters (MemberSpec member)
4238 if (queried_type == member.DeclaringType)
4241 return MemberCache.FindMember (queried_type, new MemberFilter ((MethodSpec) member),
4242 BindingRestriction.InstanceOnly | BindingRestriction.OverrideOnly) as IParametersMember;
4246 // Extension methods lookup after ordinary methods candidates failed to apply
4248 public virtual MethodGroupExpr LookupExtensionMethod (ResolveContext rc)
4250 if (InstanceExpression == null || InstanceExpression.eclass == ExprClass.Type)
4253 if (!IsExtensionMethodArgument (InstanceExpression))
4256 int arity = type_arguments == null ? 0 : type_arguments.Count;
4257 var methods = rc.LookupExtensionMethod (Methods[0].Name, arity);
4258 if (methods == null)
4261 var emg = new ExtensionMethodGroupExpr (methods, InstanceExpression, loc);
4262 emg.SetTypeArguments (rc, type_arguments);
4263 emg.ConditionalAccess = ConditionalAccess;
4270 struct ConstructorInstanceQualifier : OverloadResolver.IInstanceQualifier
4272 public ConstructorInstanceQualifier (TypeSpec type)
4275 InstanceType = type;
4278 public TypeSpec InstanceType { get; private set; }
4280 public bool CheckProtectedMemberAccess (ResolveContext rc, MemberSpec member)
4282 return MemberExpr.CheckProtectedMemberAccess (rc, member, InstanceType);
4286 public struct OverloadResolver
4289 public enum Restrictions
4293 ProbingOnly = 1 << 1,
4294 CovariantDelegate = 1 << 2,
4295 NoBaseMembers = 1 << 3,
4296 BaseMembersIncluded = 1 << 4,
4297 GetEnumeratorLookup = 1 << 5
4300 public interface IBaseMembersProvider
4302 IList<MemberSpec> GetBaseMembers (TypeSpec baseType);
4303 IParametersMember GetOverrideMemberParameters (MemberSpec member);
4304 MethodGroupExpr LookupExtensionMethod (ResolveContext rc);
4307 public interface IErrorHandler
4309 bool AmbiguousCandidates (ResolveContext rc, MemberSpec best, MemberSpec ambiguous);
4310 bool ArgumentMismatch (ResolveContext rc, MemberSpec best, Argument a, int index);
4311 bool NoArgumentMatch (ResolveContext rc, MemberSpec best);
4312 bool TypeInferenceFailed (ResolveContext rc, MemberSpec best);
4315 public interface IInstanceQualifier
4317 TypeSpec InstanceType { get; }
4318 bool CheckProtectedMemberAccess (ResolveContext rc, MemberSpec member);
4321 sealed class NoBaseMembers : IBaseMembersProvider
4323 public static readonly IBaseMembersProvider Instance = new NoBaseMembers ();
4325 public IList<MemberSpec> GetBaseMembers (TypeSpec baseType)
4330 public IParametersMember GetOverrideMemberParameters (MemberSpec member)
4335 public MethodGroupExpr LookupExtensionMethod (ResolveContext rc)
4341 struct AmbiguousCandidate
4343 public readonly MemberSpec Member;
4344 public readonly bool Expanded;
4345 public readonly AParametersCollection Parameters;
4347 public AmbiguousCandidate (MemberSpec member, AParametersCollection parameters, bool expanded)
4350 Parameters = parameters;
4351 Expanded = expanded;
4356 IList<MemberSpec> members;
4357 TypeArguments type_arguments;
4358 IBaseMembersProvider base_provider;
4359 IErrorHandler custom_errors;
4360 IInstanceQualifier instance_qualifier;
4361 Restrictions restrictions;
4362 MethodGroupExpr best_candidate_extension_group;
4363 TypeSpec best_candidate_return_type;
4365 SessionReportPrinter lambda_conv_msgs;
4367 public OverloadResolver (IList<MemberSpec> members, Restrictions restrictions, Location loc)
4368 : this (members, null, restrictions, loc)
4372 public OverloadResolver (IList<MemberSpec> members, TypeArguments targs, Restrictions restrictions, Location loc)
4375 if (members == null || members.Count == 0)
4376 throw new ArgumentException ("empty members set");
4378 this.members = members;
4380 type_arguments = targs;
4381 this.restrictions = restrictions;
4382 if (IsDelegateInvoke)
4383 this.restrictions |= Restrictions.NoBaseMembers;
4385 base_provider = NoBaseMembers.Instance;
4390 public IBaseMembersProvider BaseMembersProvider {
4392 return base_provider;
4395 base_provider = value;
4399 public bool BestCandidateIsDynamic { get; set; }
4402 // Best candidate was found in newly created MethodGroupExpr, used by extension methods
4404 public MethodGroupExpr BestCandidateNewMethodGroup {
4406 return best_candidate_extension_group;
4411 // Return type can be different between best candidate and closest override
4413 public TypeSpec BestCandidateReturnType {
4415 return best_candidate_return_type;
4419 public IErrorHandler CustomErrors {
4421 return custom_errors;
4424 custom_errors = value;
4428 TypeSpec DelegateType {
4430 if ((restrictions & Restrictions.DelegateInvoke) == 0)
4431 throw new InternalErrorException ("Not running in delegate mode", loc);
4433 return members [0].DeclaringType;
4437 public IInstanceQualifier InstanceQualifier {
4439 return instance_qualifier;
4442 instance_qualifier = value;
4446 bool IsProbingOnly {
4448 return (restrictions & Restrictions.ProbingOnly) != 0;
4452 bool IsDelegateInvoke {
4454 return (restrictions & Restrictions.DelegateInvoke) != 0;
4461 // 7.4.3.3 Better conversion from expression
4462 // Returns : 1 if a->p is better,
4463 // 2 if a->q is better,
4464 // 0 if neither is better
4466 static int BetterExpressionConversion (ResolveContext ec, Argument a, TypeSpec p, TypeSpec q)
4468 TypeSpec argument_type = a.Type;
4471 // Exactly matching Expression phase
4475 // If argument is an anonymous function
4477 if (argument_type == InternalType.AnonymousMethod && ec.Module.Compiler.Settings.Version > LanguageVersion.ISO_2) {
4479 // p and q are delegate types or expression tree types
4481 if (p.IsExpressionTreeType || q.IsExpressionTreeType) {
4482 if (q.MemberDefinition != p.MemberDefinition) {
4487 // Uwrap delegate from Expression<T>
4489 q = TypeManager.GetTypeArguments (q) [0];
4490 p = TypeManager.GetTypeArguments (p) [0];
4493 var p_m = Delegate.GetInvokeMethod (p);
4494 var q_m = Delegate.GetInvokeMethod (q);
4497 // With identical parameter lists
4499 if (!TypeSpecComparer.Equals (p_m.Parameters.Types, q_m.Parameters.Types))
4507 // if p is void returning, and q has a return type Y, then C2 is the better conversion.
4509 if (p.Kind == MemberKind.Void) {
4510 return q.Kind != MemberKind.Void ? 2 : 0;
4514 // if p has a return type Y, and q is void returning, then C1 is the better conversion.
4516 if (q.Kind == MemberKind.Void) {
4517 return p.Kind != MemberKind.Void ? 1 : 0;
4520 var am = (AnonymousMethodExpression)a.Expr;
4523 // When anonymous method is an asynchronous, and P has a return type Task<Y1>, and Q has a return type Task<Y2>
4524 // better conversion is performed between underlying types Y1 and Y2
4526 if (p.IsGenericTask || q.IsGenericTask) {
4527 if (am.Block.IsAsync && p.IsGenericTask && q.IsGenericTask) {
4528 q = q.TypeArguments [0];
4529 p = p.TypeArguments [0];
4535 // An inferred return type X exists for E in the context of the parameter list, and
4536 // an identity conversion exists from X to the return type of D
4538 var inferred_type = am.InferReturnType (ec, null, orig_q);
4539 if (inferred_type != null) {
4540 if (inferred_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic)
4541 inferred_type = ec.BuiltinTypes.Object;
4543 if (inferred_type == p)
4546 if (inferred_type == q)
4552 if (argument_type == p)
4555 if (argument_type == q)
4558 return IsBetterConversionTarget (ec, p, q);
4561 static int IsBetterConversionTarget (ResolveContext rc, TypeSpec p, TypeSpec q)
4563 if ((p.Kind == MemberKind.Delegate || p.IsExpressionTreeType) && (q.Kind == MemberKind.Delegate || q.IsExpressionTreeType)) {
4565 if (p.Kind != MemberKind.Delegate) {
4566 p = TypeManager.GetTypeArguments (p) [0];
4569 if (q.Kind != MemberKind.Delegate) {
4570 q = TypeManager.GetTypeArguments (q) [0];
4573 var p_m = Delegate.GetInvokeMethod (p);
4574 var q_m = Delegate.GetInvokeMethod (q);
4580 // if p is void returning, and q has a return type Y, then C2 is the better conversion.
4582 if (p.Kind == MemberKind.Void) {
4583 return q.Kind != MemberKind.Void ? 2 : 0;
4587 // if p has a return type Y, and q is void returning, then C1 is the better conversion.
4589 if (q.Kind == MemberKind.Void) {
4590 return p.Kind != MemberKind.Void ? 1 : 0;
4593 return IsBetterConversionTarget (rc, p, q);
4596 if (p.IsGenericTask && q.IsGenericTask) {
4597 q = q.TypeArguments [0];
4598 p = p.TypeArguments [0];
4599 return IsBetterConversionTarget (rc, p, q);
4602 if (p.IsNullableType) {
4603 p = Nullable.NullableInfo.GetUnderlyingType (p);
4604 if (!BuiltinTypeSpec.IsPrimitiveTypeOrDecimal (p))
4608 // Spec expects implicit conversion check between p and q, q and p
4609 // to be done before nullable unwrapping but that's expensive operation.
4611 // Extra manual tweak is needed because BetterTypeConversion works on
4618 if (q.IsNullableType) {
4619 q = Nullable.NullableInfo.GetUnderlyingType (q);
4620 if (!BuiltinTypeSpec.IsPrimitiveTypeOrDecimal (q))
4627 return BetterTypeConversion (rc, p, q);
4631 // 7.4.3.4 Better conversion from type
4633 public static int BetterTypeConversion (ResolveContext ec, TypeSpec p, TypeSpec q)
4635 if (p == null || q == null)
4636 throw new InternalErrorException ("BetterTypeConversion got a null conversion");
4638 switch (p.BuiltinType) {
4639 case BuiltinTypeSpec.Type.Int:
4640 if (q.BuiltinType == BuiltinTypeSpec.Type.UInt || q.BuiltinType == BuiltinTypeSpec.Type.ULong)
4643 case BuiltinTypeSpec.Type.Long:
4644 if (q.BuiltinType == BuiltinTypeSpec.Type.ULong)
4647 case BuiltinTypeSpec.Type.SByte:
4648 switch (q.BuiltinType) {
4649 case BuiltinTypeSpec.Type.Byte:
4650 case BuiltinTypeSpec.Type.UShort:
4651 case BuiltinTypeSpec.Type.UInt:
4652 case BuiltinTypeSpec.Type.ULong:
4656 case BuiltinTypeSpec.Type.Short:
4657 switch (q.BuiltinType) {
4658 case BuiltinTypeSpec.Type.UShort:
4659 case BuiltinTypeSpec.Type.UInt:
4660 case BuiltinTypeSpec.Type.ULong:
4664 case BuiltinTypeSpec.Type.Dynamic:
4665 // LAMESPEC: Dynamic conversions is not considered
4666 p = ec.Module.Compiler.BuiltinTypes.Object;
4670 switch (q.BuiltinType) {
4671 case BuiltinTypeSpec.Type.Int:
4672 if (p.BuiltinType == BuiltinTypeSpec.Type.UInt || p.BuiltinType == BuiltinTypeSpec.Type.ULong)
4675 case BuiltinTypeSpec.Type.Long:
4676 if (p.BuiltinType == BuiltinTypeSpec.Type.ULong)
4679 case BuiltinTypeSpec.Type.SByte:
4680 switch (p.BuiltinType) {
4681 case BuiltinTypeSpec.Type.Byte:
4682 case BuiltinTypeSpec.Type.UShort:
4683 case BuiltinTypeSpec.Type.UInt:
4684 case BuiltinTypeSpec.Type.ULong:
4688 case BuiltinTypeSpec.Type.Short:
4689 switch (p.BuiltinType) {
4690 case BuiltinTypeSpec.Type.UShort:
4691 case BuiltinTypeSpec.Type.UInt:
4692 case BuiltinTypeSpec.Type.ULong:
4696 case BuiltinTypeSpec.Type.Dynamic:
4697 // LAMESPEC: Dynamic conversions is not considered
4698 q = ec.Module.Compiler.BuiltinTypes.Object;
4702 // TODO: this is expensive
4703 Expression p_tmp = new EmptyExpression (p);
4704 Expression q_tmp = new EmptyExpression (q);
4706 bool p_to_q = Convert.ImplicitConversionExists (ec, p_tmp, q);
4707 bool q_to_p = Convert.ImplicitConversionExists (ec, q_tmp, p);
4709 if (p_to_q && !q_to_p)
4712 if (q_to_p && !p_to_q)
4719 /// Determines "Better function" between candidate
4720 /// and the current best match
4723 /// Returns a boolean indicating :
4724 /// false if candidate ain't better
4725 /// true if candidate is better than the current best match
4727 bool BetterFunction (ResolveContext ec, Arguments args, MemberSpec candidate, AParametersCollection cparam, bool candidate_params,
4728 MemberSpec best, AParametersCollection bparam, bool best_params)
4730 AParametersCollection candidate_pd = ((IParametersMember) candidate).Parameters;
4731 AParametersCollection best_pd = ((IParametersMember) best).Parameters;
4733 int candidate_better_count = 0;
4734 int best_better_count = 0;
4736 bool are_equivalent = true;
4737 int args_count = args == null ? 0 : args.Count;
4741 for (int c_idx = 0, b_idx = 0; j < args_count; ++j, ++c_idx, ++b_idx) {
4744 // Default arguments are ignored for better decision
4745 if (a.IsDefaultArgument)
4749 // When comparing named argument the parameter type index has to be looked up
4750 // in original parameter set (override version for virtual members)
4752 NamedArgument na = a as NamedArgument;
4754 int idx = cparam.GetParameterIndexByName (na.Name);
4755 ct = candidate_pd.Types[idx];
4756 if (candidate_params && candidate_pd.FixedParameters[idx].ModFlags == Parameter.Modifier.PARAMS)
4757 ct = TypeManager.GetElementType (ct);
4759 idx = bparam.GetParameterIndexByName (na.Name);
4760 bt = best_pd.Types[idx];
4761 if (best_params && best_pd.FixedParameters[idx].ModFlags == Parameter.Modifier.PARAMS)
4762 bt = TypeManager.GetElementType (bt);
4764 ct = candidate_pd.Types[c_idx];
4765 bt = best_pd.Types[b_idx];
4767 if (candidate_params && candidate_pd.FixedParameters[c_idx].ModFlags == Parameter.Modifier.PARAMS) {
4768 ct = TypeManager.GetElementType (ct);
4772 if (best_params && best_pd.FixedParameters[b_idx].ModFlags == Parameter.Modifier.PARAMS) {
4773 bt = TypeManager.GetElementType (bt);
4778 if (TypeSpecComparer.IsEqual (ct, bt))
4781 are_equivalent = false;
4782 int result = BetterExpressionConversion (ec, a, ct, bt);
4784 // for each argument, the conversion to 'ct' should be no worse than
4785 // the conversion to 'bt'.
4788 // No optional parameters tie breaking rules for delegates overload resolution
4790 if ((restrictions & Restrictions.CovariantDelegate) != 0)
4793 ++best_better_count;
4797 // for at least one argument, the conversion to 'ct' should be better than
4798 // the conversion to 'bt'.
4800 ++candidate_better_count;
4803 if (candidate_better_count != 0 && best_better_count == 0)
4806 if (best_better_count > 0 && candidate_better_count == 0)
4810 // LAMESPEC: Tie-breaking rules for not equivalent parameter types
4812 if (!are_equivalent) {
4813 while (j < args_count && !args [j++].IsDefaultArgument) ;
4816 // A candidate with no default parameters is still better when there
4817 // is no better expression conversion
4819 if (candidate_pd.Count < best_pd.Count) {
4820 if (!candidate_params && !candidate_pd.FixedParameters [j - j].HasDefaultValue) {
4823 } else if (candidate_pd.Count == best_pd.Count) {
4824 if (candidate_params)
4827 if (!candidate_pd.FixedParameters [j - 1].HasDefaultValue && best_pd.FixedParameters [j - 1].HasDefaultValue)
4830 if (candidate_pd.FixedParameters [j - 1].HasDefaultValue && best_pd.HasParams)
4838 // If candidate is applicable in its normal form and best has a params array and is applicable
4839 // only in its expanded form, then candidate is better
4841 if (candidate_params != best_params)
4842 return !candidate_params;
4845 // We have not reached end of parameters list due to params or used default parameters
4847 bool defaults_ambiguity = false;
4848 while (j < candidate_pd.Count && j < best_pd.Count) {
4849 var cand_param = candidate_pd.FixedParameters [j];
4850 var best_param = best_pd.FixedParameters [j];
4852 if (cand_param.HasDefaultValue != best_param.HasDefaultValue && (!candidate_pd.HasParams || !best_pd.HasParams))
4853 return cand_param.HasDefaultValue;
4855 defaults_ambiguity = true;
4856 if (candidate_pd.Count == best_pd.Count) {
4860 // void Foo (int i = 0) is better than void Foo (params int[]) for Foo ()
4861 // void Foo (string[] s, string value = null) is better than Foo (string s, params string[]) for Foo (null) or Foo ()
4863 if (cand_param.HasDefaultValue) {
4872 // Neither is better when not all arguments are provided
4874 // void Foo (string s, int i = 0) <-> Foo (string s, int i = 0, int i2 = 0)
4875 // void Foo (string s, int i = 0) <-> Foo (string s, byte i = 0)
4876 // void Foo (string s, params int[]) <-> Foo (string s, params byte[])
4881 if (candidate_pd.Count != best_pd.Count) {
4882 if (defaults_ambiguity && best_pd.Count - 1 == j)
4883 return best_pd.HasParams;
4885 return candidate_pd.Count < best_pd.Count;
4889 // One is a non-generic method and second is a generic method, then non-generic is better
4891 if (best.IsGeneric != candidate.IsGeneric)
4892 return best.IsGeneric;
4895 // Both methods have the same number of parameters, and the parameters have equal types
4896 // Pick the "more specific" signature using rules over original (non-inflated) types
4898 var candidate_def_pd = ((IParametersMember) candidate.MemberDefinition).Parameters;
4899 var best_def_pd = ((IParametersMember) best.MemberDefinition).Parameters;
4901 bool specific_at_least_once = false;
4902 for (j = 0; j < args_count; ++j) {
4903 NamedArgument na = args_count == 0 ? null : args [j] as NamedArgument;
4905 ct = candidate_def_pd.Types[cparam.GetParameterIndexByName (na.Name)];
4906 bt = best_def_pd.Types[bparam.GetParameterIndexByName (na.Name)];
4908 ct = candidate_def_pd.Types[j];
4909 bt = best_def_pd.Types[j];
4914 TypeSpec specific = MoreSpecific (ct, bt);
4918 specific_at_least_once = true;
4921 if (specific_at_least_once)
4927 static bool CheckInflatedArguments (MethodSpec ms)
4929 if (!TypeParameterSpec.HasAnyTypeParameterTypeConstrained (ms.GenericDefinition))
4932 // Setup constraint checker for probing only
4933 ConstraintChecker cc = new ConstraintChecker (null);
4935 var mp = ms.Parameters.Types;
4936 for (int i = 0; i < mp.Length; ++i) {
4937 var type = mp[i] as InflatedTypeSpec;
4941 var targs = type.TypeArguments;
4942 if (targs.Length == 0)
4945 // TODO: Checking inflated MVAR arguments should be enough
4946 if (!cc.CheckAll (type.GetDefinition (), targs, type.Constraints, Location.Null))
4953 public static void Error_ConstructorMismatch (ResolveContext rc, TypeSpec type, int argCount, Location loc)
4955 rc.Report.Error (1729, loc,
4956 "The type `{0}' does not contain a constructor that takes `{1}' arguments",
4957 type.GetSignatureForError (), argCount.ToString ());
4961 // Determines if the candidate method is applicable to the given set of arguments
4962 // There could be two different set of parameters for same candidate where one
4963 // is the closest override for default values and named arguments checks and second
4964 // one being the virtual base for the parameter types and modifiers.
4966 // A return value rates candidate method compatibility,
4968 // 0 = the best, int.MaxValue = the worst
4970 int IsApplicable (ResolveContext ec, ref Arguments arguments, int arg_count, ref MemberSpec candidate, IParametersMember pm, ref bool params_expanded_form, ref bool dynamicArgument, ref TypeSpec returnType, bool errorMode)
4973 // Each step has allocated 10 values, it can overflow for
4974 // more than 10 arguments but that's ok as it's used for
4975 // better error reporting only
4977 const int ArgumentCountMismatch = 1000000000;
4978 const int NamedArgumentsMismatch = 100000000;
4979 const int DefaultArgumentMismatch = 10000000;
4980 const int UnexpectedTypeArguments = 1000000;
4981 const int TypeArgumentsMismatch = 100000;
4982 const int InflatedTypesMismatch = 10000;
4984 // Parameters of most-derived type used mainly for named and optional parameters
4985 var pd = pm.Parameters;
4987 // Used for params modifier only, that's legacy of C# 1.0 which uses base type for
4988 // params modifier instead of most-derived type
4989 var cpd = ((IParametersMember) candidate).Parameters;
4990 int param_count = pd.Count;
4991 int optional_count = 0;
4993 Arguments orig_args = arguments;
4995 if (arg_count != param_count) {
4997 // No arguments expansion when doing exact match for delegates
4999 if ((restrictions & Restrictions.CovariantDelegate) == 0) {
5000 for (int i = 0; i < pd.Count; ++i) {
5001 if (pd.FixedParameters[i].HasDefaultValue) {
5002 optional_count = pd.Count - i;
5008 if (optional_count != 0) {
5009 // Readjust expected number when params used
5010 if (cpd.HasParams) {
5012 if (arg_count < param_count)
5014 } else if (arg_count > param_count) {
5015 int args_gap = System.Math.Abs (arg_count - param_count);
5016 return ArgumentCountMismatch + args_gap;
5017 } else if (arg_count < param_count - optional_count) {
5018 int args_gap = System.Math.Abs (param_count - optional_count - arg_count);
5019 return ArgumentCountMismatch + args_gap;
5021 } else if (arg_count != param_count) {
5022 int args_gap = System.Math.Abs (arg_count - param_count);
5024 return ArgumentCountMismatch + args_gap;
5025 if (arg_count < param_count - 1)
5026 return ArgumentCountMismatch + args_gap;
5029 // Resize to fit optional arguments
5030 if (optional_count != 0) {
5031 if (arguments == null) {
5032 arguments = new Arguments (optional_count);
5034 // Have to create a new container, so the next run can do same
5035 var resized = new Arguments (param_count);
5036 resized.AddRange (arguments);
5037 arguments = resized;
5040 for (int i = arg_count; i < param_count; ++i)
5041 arguments.Add (null);
5045 if (arg_count > 0) {
5047 // Shuffle named arguments to the right positions if there are any
5049 if (arguments[arg_count - 1] is NamedArgument) {
5050 arg_count = arguments.Count;
5052 for (int i = 0; i < arg_count; ++i) {
5053 bool arg_moved = false;
5055 NamedArgument na = arguments[i] as NamedArgument;
5059 int index = pd.GetParameterIndexByName (na.Name);
5061 // Named parameter not found
5063 return NamedArgumentsMismatch - i;
5065 // already reordered
5070 if (index >= param_count) {
5071 // When using parameters which should not be available to the user
5072 if ((cpd.FixedParameters[index].ModFlags & Parameter.Modifier.PARAMS) == 0)
5075 arguments.Add (null);
5079 if (index == arg_count)
5080 return NamedArgumentsMismatch - i - 1;
5082 temp = arguments [index];
5084 // The slot has been taken by positional argument
5085 if (temp != null && !(temp is NamedArgument))
5090 arguments = arguments.MarkOrderedArgument (na);
5094 if (arguments == orig_args) {
5095 arguments = new Arguments (orig_args.Count);
5096 arguments.AddRange (orig_args);
5099 arguments[index] = arguments[i];
5100 arguments[i] = temp;
5107 arg_count = arguments.Count;
5109 } else if (arguments != null) {
5110 arg_count = arguments.Count;
5114 // Don't do any expensive checks when the candidate cannot succeed
5116 if (arg_count != param_count && !cpd.HasParams)
5117 return DefaultArgumentMismatch - System.Math.Abs (param_count - arg_count);
5119 var dep = candidate.GetMissingDependencies ();
5121 ImportedTypeDefinition.Error_MissingDependency (ec, dep, loc);
5126 // 1. Handle generic method using type arguments when specified or type inference
5129 var ms = candidate as MethodSpec;
5130 if (ms != null && ms.IsGeneric) {
5131 if (type_arguments != null) {
5132 var g_args_count = ms.Arity;
5133 if (g_args_count != type_arguments.Count)
5134 return TypeArgumentsMismatch - System.Math.Abs (type_arguments.Count - g_args_count);
5136 if (type_arguments.Arguments != null)
5137 ms = ms.MakeGenericMethod (ec, type_arguments.Arguments);
5140 // Deploy custom error reporting for infered anonymous expression or lambda methods. When
5141 // probing lambda methods keep all errors reported in separate set and once we are done and no best
5142 // candidate was found use the set to report more details about what was wrong with lambda body.
5143 // The general idea is to distinguish between code errors and errors caused by
5144 // trial-and-error type inference
5146 if (lambda_conv_msgs == null) {
5147 for (int i = 0; i < arg_count; i++) {
5148 Argument a = arguments[i];
5152 var am = a.Expr as AnonymousMethodExpression;
5154 if (lambda_conv_msgs == null)
5155 lambda_conv_msgs = new SessionReportPrinter ();
5157 am.TypeInferenceReportPrinter = lambda_conv_msgs;
5162 var ti = new TypeInference (arguments);
5163 TypeSpec[] i_args = ti.InferMethodArguments (ec, ms);
5166 return TypeArgumentsMismatch - ti.InferenceScore;
5169 // Clear any error messages when the result was success
5171 if (lambda_conv_msgs != null)
5172 lambda_conv_msgs.ClearSession ();
5174 if (i_args.Length != 0) {
5176 for (int i = 0; i < i_args.Length; ++i) {
5177 var ta = i_args [i];
5178 if (!ta.IsAccessible (ec))
5179 return TypeArgumentsMismatch - i;
5183 ms = ms.MakeGenericMethod (ec, i_args);
5188 // Type arguments constraints have to match for the method to be applicable
5190 if (!CheckInflatedArguments (ms)) {
5192 return InflatedTypesMismatch;
5196 // We have a generic return type and at same time the method is override which
5197 // means we have to also inflate override return type in case the candidate is
5198 // best candidate and override return type is different to base return type.
5200 // virtual Foo<T, object> with override Foo<T, dynamic>
5202 if (candidate != pm) {
5203 MethodSpec override_ms = (MethodSpec) pm;
5204 var inflator = new TypeParameterInflator (ec, ms.DeclaringType, override_ms.GenericDefinition.TypeParameters, ms.TypeArguments);
5205 returnType = inflator.Inflate (returnType);
5207 returnType = ms.ReturnType;
5214 if (type_arguments != null)
5215 return UnexpectedTypeArguments;
5221 // 2. Each argument has to be implicitly convertible to method parameter
5223 Parameter.Modifier p_mod = 0;
5226 for (int i = 0; i < arg_count; i++) {
5227 Argument a = arguments[i];
5229 var fp = pd.FixedParameters[i];
5230 if (!fp.HasDefaultValue) {
5231 arguments = orig_args;
5232 return arg_count * 2 + 2;
5236 // Get the default value expression, we can use the same expression
5237 // if the type matches
5239 Expression e = fp.DefaultValue;
5241 e = ResolveDefaultValueArgument (ec, ptypes[i], e, loc);
5243 // Restore for possible error reporting
5244 for (int ii = i; ii < arg_count; ++ii)
5245 arguments.RemoveAt (i);
5247 return (arg_count - i) * 2 + 1;
5251 if ((fp.ModFlags & Parameter.Modifier.CallerMask) != 0) {
5253 // LAMESPEC: Attributes can be mixed together with build-in priority
5255 if ((fp.ModFlags & Parameter.Modifier.CallerLineNumber) != 0) {
5256 e = new IntLiteral (ec.BuiltinTypes, loc.Row, loc);
5257 } else if ((fp.ModFlags & Parameter.Modifier.CallerFilePath) != 0) {
5258 e = new StringLiteral (ec.BuiltinTypes, loc.NameFullPath, loc);
5259 } else if (ec.MemberContext.CurrentMemberDefinition != null) {
5260 e = new StringLiteral (ec.BuiltinTypes, ec.MemberContext.CurrentMemberDefinition.GetCallerMemberName (), loc);
5264 arguments[i] = new Argument (e, Argument.AType.Default);
5268 if (p_mod != Parameter.Modifier.PARAMS) {
5269 p_mod = (pd.FixedParameters[i].ModFlags & ~Parameter.Modifier.PARAMS) | (cpd.FixedParameters[i].ModFlags & Parameter.Modifier.PARAMS);
5271 } else if (!params_expanded_form) {
5272 params_expanded_form = true;
5273 pt = ((ElementTypeSpec) pt).Element;
5279 if (!params_expanded_form) {
5280 if (a.IsExtensionType) {
5281 if (ExtensionMethodGroupExpr.IsExtensionTypeCompatible (a.Type, pt)) {
5286 score = IsArgumentCompatible (ec, a, p_mod, pt);
5289 dynamicArgument = true;
5294 // It can be applicable in expanded form (when not doing exact match like for delegates)
5296 if (score != 0 && (p_mod & Parameter.Modifier.PARAMS) != 0 && (restrictions & Restrictions.CovariantDelegate) == 0) {
5297 if (!params_expanded_form) {
5298 pt = ((ElementTypeSpec) pt).Element;
5302 score = IsArgumentCompatible (ec, a, Parameter.Modifier.NONE, pt);
5305 params_expanded_form = true;
5306 dynamicArgument = true;
5307 } else if (score == 0 || arg_count > pd.Count) {
5308 params_expanded_form = true;
5313 if (params_expanded_form)
5315 return (arg_count - i) * 2 + score;
5320 // Restore original arguments for dynamic binder to keep the intention of original source code
5322 if (dynamicArgument)
5323 arguments = orig_args;
5328 public static Expression ResolveDefaultValueArgument (ResolveContext ec, TypeSpec ptype, Expression e, Location loc)
5330 if (e is Constant && e.Type == ptype)
5334 // LAMESPEC: No idea what the exact rules are for System.Reflection.Missing.Value instead of null
5336 if (e == EmptyExpression.MissingValue && (ptype.BuiltinType == BuiltinTypeSpec.Type.Object || ptype.BuiltinType == BuiltinTypeSpec.Type.Dynamic)) {
5337 e = new MemberAccess (new MemberAccess (new MemberAccess (
5338 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "System", loc), "Reflection", loc), "Missing", loc), "Value", loc);
5339 } else if (e is Constant) {
5341 // Handles int to int? conversions, DefaultParameterValue check
5343 e = Convert.ImplicitConversionStandard (ec, e, ptype, loc);
5347 e = new DefaultValueExpression (new TypeExpression (ptype, loc), loc);
5350 return e.Resolve (ec);
5354 // Tests argument compatibility with the parameter
5355 // The possible return values are
5357 // 1 - modifier mismatch
5358 // 2 - type mismatch
5359 // -1 - dynamic binding required
5361 int IsArgumentCompatible (ResolveContext ec, Argument argument, Parameter.Modifier param_mod, TypeSpec parameter)
5364 // Types have to be identical when ref or out modifer
5365 // is used and argument is not of dynamic type
5367 if (((argument.Modifier | param_mod) & Parameter.Modifier.RefOutMask) != 0) {
5368 var arg_type = argument.Type;
5370 if ((argument.Modifier & Parameter.Modifier.RefOutMask) != (param_mod & Parameter.Modifier.RefOutMask)) {
5372 // Using dynamic for ref/out parameter can still succeed at runtime
5374 if (arg_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (argument.Modifier & Parameter.Modifier.RefOutMask) == 0 && (restrictions & Restrictions.CovariantDelegate) == 0)
5380 if (arg_type != parameter) {
5381 if (arg_type == InternalType.VarOutType)
5385 // Do full equality check after quick path
5387 if (!TypeSpecComparer.IsEqual (arg_type, parameter)) {
5389 // Using dynamic for ref/out parameter can still succeed at runtime
5391 if (arg_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (argument.Modifier & Parameter.Modifier.RefOutMask) == 0 && (restrictions & Restrictions.CovariantDelegate) == 0)
5399 if (argument.Type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (restrictions & Restrictions.CovariantDelegate) == 0)
5403 // Use implicit conversion in all modes to return same candidates when the expression
5404 // is used as argument or delegate conversion
5406 if (!Convert.ImplicitConversionExists (ec, argument.Expr, parameter)) {
5407 return parameter.IsDelegate && argument.Expr is AnonymousMethodExpression ? 2 : 3;
5414 static TypeSpec MoreSpecific (TypeSpec p, TypeSpec q)
5416 if (TypeManager.IsGenericParameter (p) && !TypeManager.IsGenericParameter (q))
5418 if (!TypeManager.IsGenericParameter (p) && TypeManager.IsGenericParameter (q))
5421 var ac_p = p as ArrayContainer;
5423 var ac_q = q as ArrayContainer;
5427 TypeSpec specific = MoreSpecific (ac_p.Element, ac_q.Element);
5428 if (specific == ac_p.Element)
5430 if (specific == ac_q.Element)
5432 } else if (p.IsGeneric && q.IsGeneric) {
5433 var pargs = TypeManager.GetTypeArguments (p);
5434 var qargs = TypeManager.GetTypeArguments (q);
5436 bool p_specific_at_least_once = false;
5437 bool q_specific_at_least_once = false;
5439 for (int i = 0; i < pargs.Length; i++) {
5440 TypeSpec specific = MoreSpecific (pargs[i], qargs[i]);
5441 if (specific == pargs[i])
5442 p_specific_at_least_once = true;
5443 if (specific == qargs[i])
5444 q_specific_at_least_once = true;
5447 if (p_specific_at_least_once && !q_specific_at_least_once)
5449 if (!p_specific_at_least_once && q_specific_at_least_once)
5457 // Find the best method from candidate list
5459 public T ResolveMember<T> (ResolveContext rc, ref Arguments args) where T : MemberSpec, IParametersMember
5461 List<AmbiguousCandidate> ambiguous_candidates = null;
5463 MemberSpec best_candidate;
5464 Arguments best_candidate_args = null;
5465 bool best_candidate_params = false;
5466 bool best_candidate_dynamic = false;
5467 int best_candidate_rate;
5468 IParametersMember best_parameter_member = null;
5470 int args_count = args != null ? args.Count : 0;
5472 Arguments candidate_args = args;
5473 bool error_mode = false;
5474 MemberSpec invocable_member = null;
5475 int applicable_candidates = 0;
5478 best_candidate = null;
5479 best_candidate_rate = int.MaxValue;
5481 var type_members = members;
5483 for (int i = 0; i < type_members.Count; ++i) {
5484 var member = type_members[i];
5487 // Methods in a base class are not candidates if any method in a derived
5488 // class is applicable
5490 if ((member.Modifiers & Modifiers.OVERRIDE) != 0)
5494 if (!member.IsAccessible (rc))
5497 if (rc.IsRuntimeBinder && !member.DeclaringType.IsAccessible (rc))
5500 if ((member.Modifiers & (Modifiers.PROTECTED | Modifiers.STATIC)) == Modifiers.PROTECTED &&
5501 instance_qualifier != null && !instance_qualifier.CheckProtectedMemberAccess (rc, member)) {
5506 IParametersMember pm = member as IParametersMember;
5509 // Will use it later to report ambiguity between best method and invocable member
5511 if (Invocation.IsMemberInvocable (member))
5512 invocable_member = member;
5518 // Overload resolution is looking for base member but using parameter names
5519 // and default values from the closest member. That means to do expensive lookup
5520 // for the closest override for virtual or abstract members
5522 if ((member.Modifiers & (Modifiers.VIRTUAL | Modifiers.ABSTRACT)) != 0) {
5523 var override_params = base_provider.GetOverrideMemberParameters (member);
5524 if (override_params != null)
5525 pm = override_params;
5529 // Check if the member candidate is applicable
5531 bool params_expanded_form = false;
5532 bool dynamic_argument = false;
5533 TypeSpec rt = pm.MemberType;
5534 int candidate_rate = IsApplicable (rc, ref candidate_args, args_count, ref member, pm, ref params_expanded_form, ref dynamic_argument, ref rt, error_mode);
5536 if (lambda_conv_msgs != null)
5537 lambda_conv_msgs.EndSession ();
5540 // How does it score compare to others
5542 if (candidate_rate < best_candidate_rate) {
5544 // Fatal error (missing dependency), cannot continue
5545 if (candidate_rate < 0)
5548 applicable_candidates = 1;
5549 if ((restrictions & Restrictions.GetEnumeratorLookup) != 0 && candidate_args.Count != 0) {
5550 // Only parameterless methods are considered
5552 best_candidate_rate = candidate_rate;
5553 best_candidate = member;
5554 best_candidate_args = candidate_args;
5555 best_candidate_params = params_expanded_form;
5556 best_candidate_dynamic = dynamic_argument;
5557 best_parameter_member = pm;
5558 best_candidate_return_type = rt;
5560 } else if (candidate_rate == 0) {
5562 // The member look is done per type for most operations but sometimes
5563 // it's not possible like for binary operators overload because they
5564 // are unioned between 2 sides
5566 if ((restrictions & Restrictions.BaseMembersIncluded) != 0) {
5567 if (TypeSpec.IsBaseClass (best_candidate.DeclaringType, member.DeclaringType, true))
5571 ++applicable_candidates;
5573 if (best_candidate.DeclaringType.IsInterface && member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
5575 // We pack all interface members into top level type which makes the overload resolution
5576 // more complicated for interfaces. We compensate it by removing methods with same
5577 // signature when building the cache hence this path should not really be hit often
5580 // interface IA { void Foo (int arg); }
5581 // interface IB : IA { void Foo (params int[] args); }
5583 // IB::Foo is the best overload when calling IB.Foo (1)
5586 if (ambiguous_candidates != null) {
5587 foreach (var amb_cand in ambiguous_candidates) {
5588 if (member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
5597 ambiguous_candidates = null;
5600 // Is the new candidate better
5601 is_better = BetterFunction (rc, candidate_args, member, pm.Parameters, params_expanded_form, best_candidate, best_parameter_member.Parameters, best_candidate_params);
5605 best_candidate = member;
5606 best_candidate_args = candidate_args;
5607 best_candidate_params = params_expanded_form;
5608 best_candidate_dynamic = dynamic_argument;
5609 best_parameter_member = pm;
5610 best_candidate_return_type = rt;
5612 // It's not better but any other found later could be but we are not sure yet
5613 if (ambiguous_candidates == null)
5614 ambiguous_candidates = new List<AmbiguousCandidate> ();
5616 ambiguous_candidates.Add (new AmbiguousCandidate (member, pm.Parameters, params_expanded_form));
5620 // Restore expanded arguments
5621 candidate_args = args;
5623 } while (best_candidate_rate != 0 && (type_members = base_provider.GetBaseMembers (type_members[0].DeclaringType.BaseType)) != null);
5626 // We've found exact match
5628 if (best_candidate_rate == 0)
5632 // Try extension methods lookup when no ordinary method match was found and provider enables it
5635 var emg = base_provider.LookupExtensionMethod (rc);
5637 emg = emg.OverloadResolve (rc, ref args, null, restrictions);
5639 best_candidate_extension_group = emg;
5640 return (T) (MemberSpec) emg.BestCandidate;
5645 // Don't run expensive error reporting mode for probing
5652 if (lambda_conv_msgs != null && !lambda_conv_msgs.IsEmpty)
5655 lambda_conv_msgs = null;
5660 // No best member match found, report an error
5662 if (best_candidate_rate != 0 || error_mode) {
5663 ReportOverloadError (rc, best_candidate, best_parameter_member, best_candidate_args, best_candidate_params);
5667 if (best_candidate_dynamic) {
5668 if (args[0].IsExtensionType) {
5669 rc.Report.Error (1973, loc,
5670 "Type `{0}' does not contain a member `{1}' and the best extension method overload `{2}' cannot be dynamically dispatched. Consider calling the method without the extension method syntax",
5671 args [0].Type.GetSignatureForError (), best_candidate.Name, best_candidate.GetSignatureForError ());
5675 // Check type constraints only when explicit type arguments are used
5677 if (applicable_candidates == 1 && best_candidate.IsGeneric && type_arguments != null) {
5678 MethodSpec bc = best_candidate as MethodSpec;
5679 if (bc != null && TypeParameterSpec.HasAnyTypeParameterConstrained (bc.GenericDefinition)) {
5680 ConstraintChecker cc = new ConstraintChecker (rc);
5681 cc.CheckAll (bc.GetGenericMethodDefinition (), bc.TypeArguments, bc.Constraints, loc);
5685 BestCandidateIsDynamic = true;
5690 // These flags indicates we are running delegate probing conversion. No need to
5691 // do more expensive checks
5693 if ((restrictions & (Restrictions.ProbingOnly | Restrictions.CovariantDelegate)) == (Restrictions.CovariantDelegate | Restrictions.ProbingOnly))
5694 return (T) best_candidate;
5696 if (ambiguous_candidates != null) {
5698 // Now check that there are no ambiguities i.e the selected method
5699 // should be better than all the others
5701 for (int ix = 0; ix < ambiguous_candidates.Count; ix++) {
5702 var candidate = ambiguous_candidates [ix];
5704 if (!BetterFunction (rc, best_candidate_args, best_candidate, best_parameter_member.Parameters, best_candidate_params, candidate.Member, candidate.Parameters, candidate.Expanded)) {
5705 var ambiguous = candidate.Member;
5706 if (custom_errors == null || !custom_errors.AmbiguousCandidates (rc, best_candidate, ambiguous)) {
5707 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5708 rc.Report.SymbolRelatedToPreviousError (ambiguous);
5709 rc.Report.Error (121, loc, "The call is ambiguous between the following methods or properties: `{0}' and `{1}'",
5710 best_candidate.GetSignatureForError (), ambiguous.GetSignatureForError ());
5713 return (T) best_candidate;
5718 if (invocable_member != null && !IsProbingOnly) {
5719 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5720 rc.Report.SymbolRelatedToPreviousError (invocable_member);
5721 rc.Report.Warning (467, 2, loc, "Ambiguity between method `{0}' and invocable non-method `{1}'. Using method group",
5722 best_candidate.GetSignatureForError (), invocable_member.GetSignatureForError ());
5726 // And now check if the arguments are all
5727 // compatible, perform conversions if
5728 // necessary etc. and return if everything is
5731 if (!VerifyArguments (rc, ref best_candidate_args, best_candidate, best_parameter_member, best_candidate_params))
5734 if (best_candidate == null)
5738 // Don't run possibly expensive checks in probing mode
5740 if (!IsProbingOnly && !rc.IsInProbingMode) {
5742 // Check ObsoleteAttribute on the best method
5744 best_candidate.CheckObsoleteness (rc, loc);
5746 best_candidate.MemberDefinition.SetIsUsed ();
5749 args = best_candidate_args;
5750 return (T) best_candidate;
5753 public MethodSpec ResolveOperator (ResolveContext rc, ref Arguments args)
5755 return ResolveMember<MethodSpec> (rc, ref args);
5758 void ReportArgumentMismatch (ResolveContext ec, int idx, MemberSpec method,
5759 Argument a, AParametersCollection expected_par, TypeSpec paramType)
5761 if (custom_errors != null && custom_errors.ArgumentMismatch (ec, method, a, idx))
5764 if (a.Type == InternalType.ErrorType)
5767 if (a is CollectionElementInitializer.ElementInitializerArgument) {
5768 ec.Report.SymbolRelatedToPreviousError (method);
5769 if ((expected_par.FixedParameters[idx].ModFlags & Parameter.Modifier.RefOutMask) != 0) {
5770 ec.Report.Error (1954, loc, "The best overloaded collection initalizer method `{0}' cannot have `ref' or `out' modifier",
5771 TypeManager.CSharpSignature (method));
5774 ec.Report.Error (1950, loc, "The best overloaded collection initalizer method `{0}' has some invalid arguments",
5775 TypeManager.CSharpSignature (method));
5776 } else if (IsDelegateInvoke) {
5777 ec.Report.Error (1594, loc, "Delegate `{0}' has some invalid arguments",
5778 DelegateType.GetSignatureForError ());
5780 ec.Report.SymbolRelatedToPreviousError (method);
5781 ec.Report.Error (1502, loc, "The best overloaded method match for `{0}' has some invalid arguments",
5782 method.GetSignatureForError ());
5785 Parameter.Modifier mod = idx >= expected_par.Count ? 0 : expected_par.FixedParameters[idx].ModFlags;
5787 string index = (idx + 1).ToString ();
5788 if (((mod & Parameter.Modifier.RefOutMask) ^ (a.Modifier & Parameter.Modifier.RefOutMask)) != 0) {
5789 if ((mod & Parameter.Modifier.RefOutMask) == 0)
5790 ec.Report.Error (1615, a.Expr.Location, "Argument `#{0}' does not require `{1}' modifier. Consider removing `{1}' modifier",
5791 index, Parameter.GetModifierSignature (a.Modifier));
5793 ec.Report.Error (1620, a.Expr.Location, "Argument `#{0}' is missing `{1}' modifier",
5794 index, Parameter.GetModifierSignature (mod));
5796 string p1 = a.GetSignatureForError ();
5797 string p2 = paramType.GetSignatureForError ();
5800 p1 = a.Type.GetSignatureForErrorIncludingAssemblyName ();
5801 p2 = paramType.GetSignatureForErrorIncludingAssemblyName ();
5804 if ((mod & Parameter.Modifier.RefOutMask) != 0) {
5805 p1 = Parameter.GetModifierSignature (a.Modifier) + " " + p1;
5806 p2 = Parameter.GetModifierSignature (a.Modifier) + " " + p2;
5809 ec.Report.Error (1503, a.Expr.Location,
5810 "Argument `#{0}' cannot convert `{1}' expression to type `{2}'", index, p1, p2);
5815 // We have failed to find exact match so we return error info about the closest match
5817 void ReportOverloadError (ResolveContext rc, MemberSpec best_candidate, IParametersMember pm, Arguments args, bool params_expanded)
5819 int ta_count = type_arguments == null ? 0 : type_arguments.Count;
5820 int arg_count = args == null ? 0 : args.Count;
5822 if (ta_count != best_candidate.Arity && (ta_count > 0 || ((IParametersMember) best_candidate).Parameters.IsEmpty)) {
5823 var mg = new MethodGroupExpr (new [] { best_candidate }, best_candidate.DeclaringType, loc);
5824 mg.Error_TypeArgumentsCannotBeUsed (rc, best_candidate, loc);
5828 if (lambda_conv_msgs != null && lambda_conv_msgs.Merge (rc.Report.Printer)) {
5833 if ((best_candidate.Modifiers & (Modifiers.PROTECTED | Modifiers.STATIC)) == Modifiers.PROTECTED &&
5834 InstanceQualifier != null && !InstanceQualifier.CheckProtectedMemberAccess (rc, best_candidate)) {
5835 MemberExpr.Error_ProtectedMemberAccess (rc, best_candidate, InstanceQualifier.InstanceType, loc);
5839 // For candidates which match on parameters count report more details about incorrect arguments
5842 if (pm.Parameters.Count == arg_count || params_expanded || HasUnfilledParams (best_candidate, pm, args)) {
5843 // Reject any inaccessible member
5844 if (!best_candidate.IsAccessible (rc) || !best_candidate.DeclaringType.IsAccessible (rc)) {
5845 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5846 Expression.ErrorIsInaccesible (rc, best_candidate.GetSignatureForError (), loc);
5850 var ms = best_candidate as MethodSpec;
5851 if (ms != null && ms.IsGeneric) {
5852 bool constr_ok = true;
5853 if (ms.TypeArguments != null)
5854 constr_ok = new ConstraintChecker (rc.MemberContext).CheckAll (ms.GetGenericMethodDefinition (), ms.TypeArguments, ms.Constraints, loc);
5856 if (ta_count == 0 && ms.TypeArguments == null) {
5857 if (custom_errors != null && custom_errors.TypeInferenceFailed (rc, best_candidate))
5861 rc.Report.Error (411, loc,
5862 "The type arguments for method `{0}' cannot be inferred from the usage. Try specifying the type arguments explicitly",
5863 ms.GetGenericMethodDefinition ().GetSignatureForError ());
5870 VerifyArguments (rc, ref args, best_candidate, pm, params_expanded);
5876 // We failed to find any method with correct argument count, report best candidate
5878 if (custom_errors != null && custom_errors.NoArgumentMatch (rc, best_candidate))
5881 if (best_candidate.Kind == MemberKind.Constructor) {
5882 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5883 Error_ConstructorMismatch (rc, best_candidate.DeclaringType, arg_count, loc);
5884 } else if (IsDelegateInvoke) {
5885 rc.Report.SymbolRelatedToPreviousError (DelegateType);
5886 rc.Report.Error (1593, loc, "Delegate `{0}' does not take `{1}' arguments",
5887 DelegateType.GetSignatureForError (), arg_count.ToString ());
5889 string name = best_candidate.Kind == MemberKind.Indexer ? "this" : best_candidate.Name;
5890 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5891 rc.Report.Error (1501, loc, "No overload for method `{0}' takes `{1}' arguments",
5892 name, arg_count.ToString ());
5896 static bool HasUnfilledParams (MemberSpec best_candidate, IParametersMember pm, Arguments args)
5898 var p = ((IParametersMember)best_candidate).Parameters;
5903 for (int i = p.Count - 1; i != 0; --i) {
5904 var fp = p.FixedParameters [i];
5905 if ((fp.ModFlags & Parameter.Modifier.PARAMS) == 0)
5915 foreach (var arg in args) {
5916 var na = arg as NamedArgument;
5920 if (na.Name == name) {
5929 return args.Count + 1 == pm.Parameters.Count;
5932 bool VerifyArguments (ResolveContext ec, ref Arguments args, MemberSpec member, IParametersMember pm, bool chose_params_expanded)
5934 var pd = pm.Parameters;
5935 var cpd = ((IParametersMember) member).Parameters;
5936 var ptypes = cpd.Types;
5938 Parameter.Modifier p_mod = 0;
5940 int a_idx = 0, a_pos = 0;
5942 ArrayInitializer params_initializers = null;
5943 bool has_unsafe_arg = pm.MemberType.IsPointer;
5944 int arg_count = args == null ? 0 : args.Count;
5946 for (; a_idx < arg_count; a_idx++, ++a_pos) {
5951 if (p_mod != Parameter.Modifier.PARAMS) {
5952 p_mod = cpd.FixedParameters [a_idx].ModFlags;
5954 has_unsafe_arg |= pt.IsPointer;
5956 if (p_mod == Parameter.Modifier.PARAMS) {
5957 if (chose_params_expanded) {
5958 params_initializers = new ArrayInitializer (arg_count - a_idx, a.Expr.Location);
5959 pt = TypeManager.GetElementType (pt);
5965 // Types have to be identical when ref or out modifer is used
5967 if (((a.Modifier | p_mod) & Parameter.Modifier.RefOutMask) != 0) {
5968 if ((a.Modifier & Parameter.Modifier.RefOutMask) != (p_mod & Parameter.Modifier.RefOutMask))
5971 var arg_type = a.Type;
5975 if (arg_type == InternalType.VarOutType) {
5977 // Set underlying variable type based on parameter type
5979 ((DeclarationExpression)a.Expr).Variable.Type = pt;
5983 if (!TypeSpecComparer.IsEqual (arg_type, pt))
5987 NamedArgument na = a as NamedArgument;
5989 int name_index = pd.GetParameterIndexByName (na.Name);
5990 if (name_index < 0 || name_index >= pd.Count) {
5991 if (IsDelegateInvoke) {
5992 ec.Report.SymbolRelatedToPreviousError (DelegateType);
5993 ec.Report.Error (1746, na.Location,
5994 "The delegate `{0}' does not contain a parameter named `{1}'",
5995 DelegateType.GetSignatureForError (), na.Name);
5997 ec.Report.SymbolRelatedToPreviousError (member);
5998 ec.Report.Error (1739, na.Location,
5999 "The best overloaded method match for `{0}' does not contain a parameter named `{1}'",
6000 TypeManager.CSharpSignature (member), na.Name);
6002 } else if (args[name_index] != a && args[name_index] != null) {
6003 if (IsDelegateInvoke)
6004 ec.Report.SymbolRelatedToPreviousError (DelegateType);
6006 ec.Report.SymbolRelatedToPreviousError (member);
6008 ec.Report.Error (1744, na.Location,
6009 "Named argument `{0}' cannot be used for a parameter which has positional argument specified",
6014 if (a.Expr.Type.BuiltinType == BuiltinTypeSpec.Type.Dynamic)
6017 if ((restrictions & Restrictions.CovariantDelegate) != 0 && !Delegate.IsTypeCovariant (ec, a.Expr.Type, pt)) {
6018 if (a.IsExtensionType) {
6019 // TODO: Should report better message type, something similar to CS1928/1929 instead of
6020 // CS1061 but that still better than confusing CS0123
6021 var ma = new MemberAccess (a.Expr, member.Name, loc);
6022 ma.Error_TypeDoesNotContainDefinition (ec, a.Expr.Type, ma.Name);
6024 custom_errors.NoArgumentMatch (ec, member);
6030 if (a.IsExtensionType) {
6031 if (a.Expr.Type == pt || TypeSpecComparer.IsEqual (a.Expr.Type, pt)) {
6034 conv = Convert.ImplicitReferenceConversion (a.Expr, pt, false);
6036 conv = Convert.ImplicitBoxingConversion (a.Expr, a.Expr.Type, pt);
6039 conv = Convert.ImplicitConversion (ec, a.Expr, pt, loc);
6046 // Convert params arguments to an array initializer
6048 if (params_initializers != null) {
6049 // we choose to use 'a.Expr' rather than 'conv' so that
6050 // we don't hide the kind of expression we have (esp. CompoundAssign.Helper)
6051 params_initializers.Add (a.Expr);
6052 args.RemoveAt (a_idx--);
6058 // Update the argument with the implicit conversion
6062 if (a_idx != arg_count) {
6064 // Convert all var out argument to error type for less confusing error reporting
6065 // when no matching overload is found
6067 for (; a_idx < arg_count; a_idx++) {
6068 var arg = args [a_idx];
6072 if (arg.Type == InternalType.VarOutType) {
6073 ((DeclarationExpression)arg.Expr).Variable.Type = InternalType.ErrorType;
6077 ReportArgumentMismatch (ec, a_pos, member, a, pd, pt);
6082 // Fill not provided arguments required by params modifier
6084 if (params_initializers == null && arg_count + 1 == pd.Count) {
6086 args = new Arguments (1);
6088 pt = ptypes[pd.Count - 1];
6089 pt = TypeManager.GetElementType (pt);
6090 has_unsafe_arg |= pt.IsPointer;
6091 params_initializers = new ArrayInitializer (0, loc);
6095 // Append an array argument with all params arguments
6097 if (params_initializers != null) {
6098 args.Add (new Argument (
6099 new ArrayCreation (new TypeExpression (pt, loc), params_initializers, loc).Resolve (ec)));
6103 if (has_unsafe_arg && !ec.IsUnsafe) {
6104 Expression.UnsafeError (ec, loc);
6108 // We could infer inaccesible type arguments
6110 if (type_arguments == null && member.IsGeneric) {
6111 var ms = (MethodSpec) member;
6112 foreach (var ta in ms.TypeArguments) {
6113 if (!ta.IsAccessible (ec)) {
6114 ec.Report.SymbolRelatedToPreviousError (ta);
6115 Expression.ErrorIsInaccesible (ec, member.GetSignatureForError (), loc);
6125 public class ConstantExpr : MemberExpr
6127 readonly ConstSpec constant;
6129 public ConstantExpr (ConstSpec constant, Location loc)
6131 this.constant = constant;
6135 public override string Name {
6136 get { throw new NotImplementedException (); }
6139 public override string KindName {
6140 get { return "constant"; }
6143 public override bool IsInstance {
6144 get { return !IsStatic; }
6147 public override bool IsStatic {
6148 get { return true; }
6151 protected override TypeSpec DeclaringType {
6152 get { return constant.DeclaringType; }
6155 public override Expression CreateExpressionTree (ResolveContext ec)
6157 throw new NotSupportedException ("ET");
6160 protected override Expression DoResolve (ResolveContext rc)
6162 ResolveInstanceExpression (rc, null);
6163 DoBestMemberChecks (rc, constant);
6165 if (rc.HasSet (ResolveContext.Options.NameOfScope)) {
6166 eclass = ExprClass.Value;
6167 type = constant.MemberType;
6171 var c = constant.GetConstant (rc);
6173 // Creates reference expression to the constant value
6174 return Constant.CreateConstantFromValue (constant.MemberType, c.GetValue (), loc);
6177 public override void Emit (EmitContext ec)
6179 throw new NotSupportedException ();
6182 public override string GetSignatureForError ()
6184 return constant.GetSignatureForError ();
6187 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
6189 Error_TypeArgumentsCannotBeUsed (ec, "constant", GetSignatureForError (), loc);
6194 // Fully resolved expression that references a Field
6196 public class FieldExpr : MemberExpr, IDynamicAssign, IMemoryLocation, IVariableReference
6198 protected FieldSpec spec;
6199 VariableInfo variable_info;
6201 LocalTemporary temp;
6204 protected FieldExpr (Location l)
6209 public FieldExpr (FieldSpec spec, Location loc)
6214 type = spec.MemberType;
6217 public FieldExpr (FieldBase fi, Location l)
6224 public override string Name {
6230 public bool IsHoisted {
6232 IVariableReference hv = InstanceExpression as IVariableReference;
6233 return hv != null && hv.IsHoisted;
6237 public override bool IsInstance {
6239 return !spec.IsStatic;
6243 public override bool IsStatic {
6245 return spec.IsStatic;
6249 public override string KindName {
6250 get { return "field"; }
6253 public FieldSpec Spec {
6259 protected override TypeSpec DeclaringType {
6261 return spec.DeclaringType;
6265 public VariableInfo VariableInfo {
6267 return variable_info;
6273 public override string GetSignatureForError ()
6275 return spec.GetSignatureForError ();
6278 public bool IsMarshalByRefAccess (ResolveContext rc)
6280 // Checks possible ldflda of field access expression
6281 return !spec.IsStatic && TypeSpec.IsValueType (spec.MemberType) && !(InstanceExpression is This) &&
6282 rc.Module.PredefinedTypes.MarshalByRefObject.Define () &&
6283 TypeSpec.IsBaseClass (spec.DeclaringType, rc.Module.PredefinedTypes.MarshalByRefObject.TypeSpec, false);
6286 public void SetHasAddressTaken ()
6288 IVariableReference vr = InstanceExpression as IVariableReference;
6290 vr.SetHasAddressTaken ();
6294 protected override void CloneTo (CloneContext clonectx, Expression target)
6296 var t = (FieldExpr) target;
6298 if (InstanceExpression != null)
6299 t.InstanceExpression = InstanceExpression.Clone (clonectx);
6302 public override Expression CreateExpressionTree (ResolveContext ec)
6304 if (ConditionalAccess) {
6305 Error_NullShortCircuitInsideExpressionTree (ec);
6308 return CreateExpressionTree (ec, true);
6311 public Expression CreateExpressionTree (ResolveContext ec, bool convertInstance)
6314 Expression instance;
6316 if (InstanceExpression == null) {
6317 instance = new NullLiteral (loc);
6318 } else if (convertInstance) {
6319 instance = InstanceExpression.CreateExpressionTree (ec);
6321 args = new Arguments (1);
6322 args.Add (new Argument (InstanceExpression));
6323 instance = CreateExpressionFactoryCall (ec, "Constant", args);
6326 args = Arguments.CreateForExpressionTree (ec, null,
6328 CreateTypeOfExpression ());
6330 return CreateExpressionFactoryCall (ec, "Field", args);
6333 public Expression CreateTypeOfExpression ()
6335 return new TypeOfField (spec, loc);
6338 protected override Expression DoResolve (ResolveContext ec)
6340 spec.MemberDefinition.SetIsUsed ();
6342 return DoResolve (ec, null);
6345 Expression DoResolve (ResolveContext ec, Expression rhs)
6347 bool lvalue_instance = rhs != null && IsInstance && spec.DeclaringType.IsStruct;
6350 ResolveConditionalAccessReceiver (ec);
6352 if (ResolveInstanceExpression (ec, rhs)) {
6353 // Resolve the field's instance expression while flow analysis is turned
6354 // off: when accessing a field "a.b", we must check whether the field
6355 // "a.b" is initialized, not whether the whole struct "a" is initialized.
6357 if (lvalue_instance) {
6358 bool out_access = rhs == EmptyExpression.OutAccess || rhs == EmptyExpression.LValueMemberOutAccess;
6360 Expression right_side =
6361 out_access ? EmptyExpression.LValueMemberOutAccess : EmptyExpression.LValueMemberAccess;
6363 InstanceExpression = InstanceExpression.ResolveLValue (ec, right_side);
6365 InstanceExpression = InstanceExpression.Resolve (ec, ResolveFlags.VariableOrValue);
6368 if (InstanceExpression == null)
6372 DoBestMemberChecks (ec, spec);
6374 if (conditional_access_receiver)
6375 ec.With (ResolveContext.Options.DontSetConditionalAccessReceiver, false);
6378 var fb = spec as FixedFieldSpec;
6379 IVariableReference var = InstanceExpression as IVariableReference;
6382 IFixedExpression fe = InstanceExpression as IFixedExpression;
6383 if (!ec.HasSet (ResolveContext.Options.FixedInitializerScope) && (fe == null || !fe.IsFixed)) {
6384 ec.Report.Error (1666, loc, "You cannot use fixed size buffers contained in unfixed expressions. Try using the fixed statement");
6387 if (InstanceExpression.eclass != ExprClass.Variable) {
6388 ec.Report.SymbolRelatedToPreviousError (spec);
6389 ec.Report.Error (1708, loc, "`{0}': Fixed size buffers can only be accessed through locals or fields",
6390 TypeManager.GetFullNameSignature (spec));
6391 } else if (var != null && var.IsHoisted) {
6392 AnonymousMethodExpression.Error_AddressOfCapturedVar (ec, var, loc);
6395 return new FixedBufferPtr (this, fb.ElementType, loc).Resolve (ec);
6399 // Set flow-analysis variable info for struct member access. It will be check later
6400 // for precise error reporting
6402 if (var != null && var.VariableInfo != null && InstanceExpression.Type.IsStruct) {
6403 variable_info = var.VariableInfo.GetStructFieldInfo (Name);
6406 if (conditional_access_receiver)
6407 type = LiftMemberType (ec, type);
6409 if (ConditionalAccess && InstanceExpression != null && InstanceExpression.IsNull)
6410 return Constant.CreateConstantFromValue (type, null, loc);
6412 eclass = ExprClass.Variable;
6416 public void SetFieldAssigned (FlowAnalysisContext fc)
6421 bool lvalue_instance = spec.DeclaringType.IsStruct;
6422 if (lvalue_instance) {
6423 var var = InstanceExpression as IVariableReference;
6424 if (var != null && var.VariableInfo != null) {
6425 fc.SetStructFieldAssigned (var.VariableInfo, Name);
6429 var fe = InstanceExpression as FieldExpr;
6431 Expression instance;
6434 instance = fe.InstanceExpression;
6435 var fe_instance = instance as FieldExpr;
6436 if ((fe_instance != null && !fe_instance.IsStatic) || instance is LocalVariableReference) {
6437 if (TypeSpec.IsReferenceType (fe.Type) && instance.Type.IsStruct) {
6438 var var = InstanceExpression as IVariableReference;
6439 if (var != null && var.VariableInfo == null) {
6440 var var_inst = instance as IVariableReference;
6441 if (var_inst == null || (var_inst.VariableInfo != null && !fc.IsDefinitelyAssigned (var_inst.VariableInfo)))
6442 fc.Report.Warning (1060, 1, fe.loc, "Use of possibly unassigned field `{0}'", fe.Name);
6446 if (fe_instance != null) {
6455 if (instance != null && TypeSpec.IsReferenceType (instance.Type))
6456 instance.FlowAnalysis (fc);
6458 if (TypeSpec.IsReferenceType (InstanceExpression.Type))
6459 InstanceExpression.FlowAnalysis (fc);
6463 Expression Error_AssignToReadonly (ResolveContext rc, Expression right_side)
6465 // The return value is always null. Returning a value simplifies calling code.
6467 if (right_side == EmptyExpression.OutAccess) {
6469 rc.Report.Error (199, loc, "A static readonly field `{0}' cannot be passed ref or out (except in a static constructor)",
6470 GetSignatureForError ());
6472 rc.Report.Error (192, loc, "A readonly field `{0}' cannot be passed ref or out (except in a constructor)",
6473 GetSignatureForError ());
6479 if (right_side == EmptyExpression.LValueMemberAccess) {
6480 // Already reported as CS1648/CS1650
6484 if (right_side == EmptyExpression.LValueMemberOutAccess) {
6486 rc.Report.Error (1651, loc, "Fields of static readonly field `{0}' cannot be passed ref or out (except in a static constructor)",
6487 GetSignatureForError ());
6489 rc.Report.Error (1649, loc, "Members of readonly field `{0}' cannot be passed ref or out (except in a constructor)",
6490 GetSignatureForError ());
6496 rc.Report.Error (198, loc, "A static readonly field `{0}' cannot be assigned to (except in a static constructor or a variable initializer)",
6497 GetSignatureForError ());
6499 rc.Report.Error (191, loc, "A readonly field `{0}' cannot be assigned to (except in a constructor or a variable initializer)",
6500 GetSignatureForError ());
6506 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
6508 if (HasConditionalAccess ())
6509 Error_NullPropagatingLValue (ec);
6511 if (spec is FixedFieldSpec) {
6512 // It could be much better error message but we want to be error compatible
6513 Error_ValueAssignment (ec, right_side);
6516 Expression e = DoResolve (ec, right_side);
6521 spec.MemberDefinition.SetIsAssigned ();
6523 if ((right_side == EmptyExpression.UnaryAddress || right_side == EmptyExpression.OutAccess) &&
6524 (spec.Modifiers & Modifiers.VOLATILE) != 0) {
6525 ec.Report.Warning (420, 1, loc,
6526 "`{0}': A volatile field references will not be treated as volatile",
6527 spec.GetSignatureForError ());
6530 if (spec.IsReadOnly) {
6531 // InitOnly fields can only be assigned in constructors or initializers
6532 if (!ec.HasAny (ResolveContext.Options.FieldInitializerScope | ResolveContext.Options.ConstructorScope))
6533 return Error_AssignToReadonly (ec, right_side);
6535 if (ec.HasSet (ResolveContext.Options.ConstructorScope)) {
6537 // InitOnly fields cannot be assigned-to in a different constructor from their declaring type
6538 if (ec.CurrentMemberDefinition.Parent.PartialContainer.Definition != spec.DeclaringType.GetDefinition ())
6539 return Error_AssignToReadonly (ec, right_side);
6540 // static InitOnly fields cannot be assigned-to in an instance constructor
6541 if (IsStatic && !ec.IsStatic)
6542 return Error_AssignToReadonly (ec, right_side);
6543 // instance constructors can't modify InitOnly fields of other instances of the same type
6544 if (!IsStatic && !(InstanceExpression is This))
6545 return Error_AssignToReadonly (ec, right_side);
6549 if (right_side == EmptyExpression.OutAccess && IsMarshalByRefAccess (ec)) {
6550 ec.Report.SymbolRelatedToPreviousError (spec.DeclaringType);
6551 ec.Report.Warning (197, 1, loc,
6552 "Passing `{0}' as ref or out or taking its address may cause a runtime exception because it is a field of a marshal-by-reference class",
6553 GetSignatureForError ());
6556 eclass = ExprClass.Variable;
6560 public override void FlowAnalysis (FlowAnalysisContext fc)
6562 var var = InstanceExpression as IVariableReference;
6564 var vi = var.VariableInfo;
6565 if (vi != null && !fc.IsStructFieldDefinitelyAssigned (vi, Name)) {
6566 fc.Report.Error (170, loc, "Use of possibly unassigned field `{0}'", Name);
6570 if (TypeSpec.IsValueType (InstanceExpression.Type)) {
6571 var le = SkipLeftValueTypeAccess (InstanceExpression);
6573 le.FlowAnalysis (fc);
6579 var da = conditional_access_receiver ? fc.BranchDefiniteAssignment () : null;
6581 base.FlowAnalysis (fc);
6583 if (conditional_access_receiver)
6584 fc.DefiniteAssignment = da;
6587 static Expression SkipLeftValueTypeAccess (Expression expr)
6589 if (!TypeSpec.IsValueType (expr.Type))
6592 if (expr is VariableReference)
6595 var fe = expr as FieldExpr;
6599 if (fe.InstanceExpression == null)
6602 return SkipLeftValueTypeAccess (fe.InstanceExpression);
6605 public override int GetHashCode ()
6607 return spec.GetHashCode ();
6610 public bool IsFixed {
6613 // A variable of the form V.I is fixed when V is a fixed variable of a struct type
6615 IVariableReference variable = InstanceExpression as IVariableReference;
6616 if (variable != null)
6617 return InstanceExpression.Type.IsStruct && variable.IsFixed;
6619 IFixedExpression fe = InstanceExpression as IFixedExpression;
6620 return fe != null && fe.IsFixed;
6624 public override bool Equals (object obj)
6626 FieldExpr fe = obj as FieldExpr;
6630 if (spec != fe.spec)
6633 if (InstanceExpression == null || fe.InstanceExpression == null)
6636 return InstanceExpression.Equals (fe.InstanceExpression);
6639 public void Emit (EmitContext ec, bool leave_copy)
6641 bool is_volatile = (spec.Modifiers & Modifiers.VOLATILE) != 0;
6645 ec.Emit (OpCodes.Volatile);
6647 ec.Emit (OpCodes.Ldsfld, spec);
6649 var ca = ec.ConditionalAccess;
6652 if (conditional_access_receiver)
6653 ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
6655 EmitInstance (ec, false);
6658 // Optimization for build-in types
6659 if (type.IsStruct && type == ec.CurrentType && InstanceExpression.Type == type) {
6660 ec.EmitLoadFromPtr (type);
6662 var ff = spec as FixedFieldSpec;
6664 ec.Emit (OpCodes.Ldflda, spec);
6665 ec.Emit (OpCodes.Ldflda, ff.Element);
6668 ec.Emit (OpCodes.Volatile);
6670 ec.Emit (OpCodes.Ldfld, spec);
6674 if (conditional_access_receiver) {
6675 ec.CloseConditionalAccess (type.IsNullableType && type != spec.MemberType ? type : null);
6676 ec.ConditionalAccess = ca;
6681 ec.Emit (OpCodes.Dup);
6683 temp = new LocalTemporary (this.Type);
6689 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
6691 bool has_await_source = ec.HasSet (BuilderContext.Options.AsyncBody) && source.ContainsEmitWithAwait ();
6692 if (isCompound && !(source is DynamicExpressionStatement) && !has_await_source) {
6697 if (ConditionalAccess)
6698 throw new NotImplementedException ("null operator assignment");
6700 if (has_await_source)
6701 source = source.EmitToField (ec);
6703 EmitInstance (ec, prepared);
6708 if (leave_copy || ec.NotifyEvaluatorOnStore) {
6709 ec.Emit (OpCodes.Dup);
6711 temp = new LocalTemporary (this.Type);
6716 if ((spec.Modifiers & Modifiers.VOLATILE) != 0)
6717 ec.Emit (OpCodes.Volatile);
6719 spec.MemberDefinition.SetIsAssigned ();
6722 ec.Emit (OpCodes.Stsfld, spec);
6724 ec.Emit (OpCodes.Stfld, spec);
6726 if (ec.NotifyEvaluatorOnStore) {
6728 throw new NotImplementedException ("instance field write");
6731 ec.Emit (OpCodes.Dup);
6733 ec.Module.Evaluator.EmitValueChangedCallback (ec, Name, type, loc);
6744 // Emits store to field with prepared values on stack
6746 public void EmitAssignFromStack (EmitContext ec)
6749 ec.Emit (OpCodes.Stsfld, spec);
6751 ec.Emit (OpCodes.Stfld, spec);
6755 public override void Emit (EmitContext ec)
6760 public override void EmitSideEffect (EmitContext ec)
6762 bool is_volatile = (spec.Modifiers & Modifiers.VOLATILE) != 0;
6764 if (is_volatile) // || is_marshal_by_ref ())
6765 base.EmitSideEffect (ec);
6768 public virtual void AddressOf (EmitContext ec, AddressOp mode)
6770 if ((mode & AddressOp.Store) != 0)
6771 spec.MemberDefinition.SetIsAssigned ();
6772 if ((mode & AddressOp.Load) != 0)
6773 spec.MemberDefinition.SetIsUsed ();
6776 // Handle initonly fields specially: make a copy and then
6777 // get the address of the copy.
6780 if (spec.IsReadOnly){
6782 if (ec.HasSet (EmitContext.Options.ConstructorScope) && spec.DeclaringType == ec.CurrentType) {
6794 var temp = ec.GetTemporaryLocal (type);
6795 ec.Emit (OpCodes.Stloc, temp);
6796 ec.Emit (OpCodes.Ldloca, temp);
6802 ec.Emit (OpCodes.Ldsflda, spec);
6805 EmitInstance (ec, false);
6806 ec.Emit (OpCodes.Ldflda, spec);
6810 public SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source)
6812 return MakeExpression (ctx);
6815 public override SLE.Expression MakeExpression (BuilderContext ctx)
6818 return base.MakeExpression (ctx);
6820 return SLE.Expression.Field (
6821 IsStatic ? null : InstanceExpression.MakeExpression (ctx),
6822 spec.GetMetaInfo ());
6826 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
6828 Error_TypeArgumentsCannotBeUsed (ec, "field", GetSignatureForError (), loc);
6834 // Expression that evaluates to a Property.
6836 // This is not an LValue because we need to re-write the expression. We
6837 // can not take data from the stack and store it.
6839 sealed class PropertyExpr : PropertyOrIndexerExpr<PropertySpec>
6841 Arguments arguments;
6842 FieldExpr backing_field;
6844 public PropertyExpr (PropertySpec spec, Location l)
6847 best_candidate = spec;
6848 type = spec.MemberType;
6853 protected override Arguments Arguments {
6862 protected override TypeSpec DeclaringType {
6864 return best_candidate.DeclaringType;
6868 public override string Name {
6870 return best_candidate.Name;
6874 public bool IsAutoPropertyAccess {
6876 var prop = best_candidate.MemberDefinition as Property;
6877 return prop != null && prop.BackingField != null;
6881 public override bool IsInstance {
6887 public override bool IsStatic {
6889 return best_candidate.IsStatic;
6893 public override string KindName {
6894 get { return "property"; }
6897 public PropertySpec PropertyInfo {
6899 return best_candidate;
6905 public override MethodGroupExpr CanReduceLambda (AnonymousMethodBody body)
6907 if (best_candidate == null || !(best_candidate.IsStatic || InstanceExpression is This))
6910 var args_count = arguments == null ? 0 : arguments.Count;
6911 if (args_count != body.Parameters.Count && args_count == 0)
6914 var mg = MethodGroupExpr.CreatePredefined (best_candidate.Get, DeclaringType, loc);
6915 mg.InstanceExpression = InstanceExpression;
6920 public static PropertyExpr CreatePredefined (PropertySpec spec, Location loc)
6922 return new PropertyExpr (spec, loc) {
6928 public override Expression CreateExpressionTree (ResolveContext ec)
6930 if (ConditionalAccess) {
6931 Error_NullShortCircuitInsideExpressionTree (ec);
6935 if (IsSingleDimensionalArrayLength ()) {
6936 args = new Arguments (1);
6937 args.Add (new Argument (InstanceExpression.CreateExpressionTree (ec)));
6938 return CreateExpressionFactoryCall (ec, "ArrayLength", args);
6941 args = new Arguments (2);
6942 if (InstanceExpression == null)
6943 args.Add (new Argument (new NullLiteral (loc)));
6945 args.Add (new Argument (InstanceExpression.CreateExpressionTree (ec)));
6946 args.Add (new Argument (new TypeOfMethod (Getter, loc)));
6947 return CreateExpressionFactoryCall (ec, "Property", args);
6950 public Expression CreateSetterTypeOfExpression (ResolveContext rc)
6952 DoResolveLValue (rc, null);
6953 return new TypeOfMethod (Setter, loc);
6956 public override string GetSignatureForError ()
6958 return best_candidate.GetSignatureForError ();
6961 public override SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source)
6964 return base.MakeExpression (ctx);
6966 return SLE.Expression.Property (InstanceExpression.MakeExpression (ctx), (MethodInfo) Setter.GetMetaInfo ());
6970 public override SLE.Expression MakeExpression (BuilderContext ctx)
6973 return base.MakeExpression (ctx);
6975 return SLE.Expression.Property (InstanceExpression.MakeExpression (ctx), (MethodInfo) Getter.GetMetaInfo ());
6979 void Error_PropertyNotValid (ResolveContext ec)
6981 ec.Report.SymbolRelatedToPreviousError (best_candidate);
6982 ec.Report.Error (1546, loc, "Property or event `{0}' is not supported by the C# language",
6983 GetSignatureForError ());
6986 bool IsSingleDimensionalArrayLength ()
6988 if (best_candidate.DeclaringType.BuiltinType != BuiltinTypeSpec.Type.Array || !best_candidate.HasGet || Name != "Length")
6991 ArrayContainer ac = InstanceExpression.Type as ArrayContainer;
6992 return ac != null && ac.Rank == 1;
6995 public override void Emit (EmitContext ec, bool leave_copy)
6998 // Special case: length of single dimension array property is turned into ldlen
7000 if (IsSingleDimensionalArrayLength ()) {
7001 if (conditional_access_receiver) {
7002 ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
7005 EmitInstance (ec, false);
7007 ec.Emit (OpCodes.Ldlen);
7008 ec.Emit (OpCodes.Conv_I4);
7010 if (conditional_access_receiver) {
7011 ec.CloseConditionalAccess (type);
7017 base.Emit (ec, leave_copy);
7020 public override void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
7022 if (backing_field != null) {
7023 backing_field.EmitAssign (ec, source, false, false);
7028 LocalTemporary await_source_arg = null;
7030 if (isCompound && !(source is DynamicExpressionStatement)) {
7031 emitting_compound_assignment = true;
7034 if (has_await_arguments) {
7035 await_source_arg = new LocalTemporary (Type);
7036 await_source_arg.Store (ec);
7038 args = new Arguments (1);
7039 args.Add (new Argument (await_source_arg));
7042 temp = await_source_arg;
7045 has_await_arguments = false;
7050 ec.Emit (OpCodes.Dup);
7051 temp = new LocalTemporary (this.Type);
7056 args = arguments ?? new Arguments (1);
7060 temp = new LocalTemporary (this.Type);
7062 args.Add (new Argument (temp));
7064 args.Add (new Argument (source));
7068 emitting_compound_assignment = false;
7070 var call = new CallEmitter ();
7071 call.InstanceExpression = InstanceExpression;
7073 call.InstanceExpressionOnStack = true;
7075 if (ConditionalAccess) {
7076 call.ConditionalAccess = true;
7080 call.Emit (ec, Setter, args, loc);
7082 call.EmitStatement (ec, Setter, args, loc);
7089 if (await_source_arg != null) {
7090 await_source_arg.Release (ec);
7094 public override void FlowAnalysis (FlowAnalysisContext fc)
7096 var prop = best_candidate.MemberDefinition as Property;
7097 if (prop != null && prop.BackingField != null) {
7098 var var = InstanceExpression as IVariableReference;
7100 var vi = var.VariableInfo;
7101 if (vi != null && !fc.IsStructFieldDefinitelyAssigned (vi, prop.BackingField.Name)) {
7102 fc.Report.Error (8079, loc, "Use of possibly unassigned auto-implemented property `{0}'", Name);
7106 if (TypeSpec.IsValueType (InstanceExpression.Type) && InstanceExpression is VariableReference)
7111 var da = conditional_access_receiver ? fc.BranchDefiniteAssignment () : null;
7113 base.FlowAnalysis (fc);
7115 if (conditional_access_receiver)
7116 fc.DefiniteAssignment = da;
7119 protected override Expression OverloadResolve (ResolveContext rc, Expression right_side)
7121 eclass = ExprClass.PropertyAccess;
7123 if (best_candidate.IsNotCSharpCompatible) {
7124 Error_PropertyNotValid (rc);
7127 ResolveInstanceExpression (rc, right_side);
7129 if ((best_candidate.Modifiers & (Modifiers.ABSTRACT | Modifiers.VIRTUAL)) != 0 && best_candidate.DeclaringType != InstanceExpression.Type) {
7130 var filter = new MemberFilter (best_candidate.Name, 0, MemberKind.Property, null, null);
7131 var p = MemberCache.FindMember (InstanceExpression.Type, filter, BindingRestriction.InstanceOnly | BindingRestriction.OverrideOnly) as PropertySpec;
7133 type = p.MemberType;
7137 DoBestMemberChecks (rc, best_candidate);
7139 // Handling of com-imported properties with any number of default property parameters
7140 if (best_candidate.HasGet && !best_candidate.Get.Parameters.IsEmpty) {
7141 var p = best_candidate.Get.Parameters;
7142 arguments = new Arguments (p.Count);
7143 for (int i = 0; i < p.Count; ++i) {
7144 arguments.Add (new Argument (OverloadResolver.ResolveDefaultValueArgument (rc, p.Types [i], p.FixedParameters [i].DefaultValue, loc)));
7146 } else if (best_candidate.HasSet && best_candidate.Set.Parameters.Count > 1) {
7147 var p = best_candidate.Set.Parameters;
7148 arguments = new Arguments (p.Count - 1);
7149 for (int i = 0; i < p.Count - 1; ++i) {
7150 arguments.Add (new Argument (OverloadResolver.ResolveDefaultValueArgument (rc, p.Types [i], p.FixedParameters [i].DefaultValue, loc)));
7157 protected override bool ResolveAutopropertyAssignment (ResolveContext rc, Expression rhs)
7159 if (!rc.HasSet (ResolveContext.Options.ConstructorScope))
7162 var prop = best_candidate.MemberDefinition as Property;
7163 if (prop == null || prop.Parent.PartialContainer != rc.CurrentMemberDefinition.Parent.PartialContainer) {
7164 var ps = MemberCache.FindMember (rc.CurrentType, MemberFilter.Property (best_candidate.Name, best_candidate.MemberType), BindingRestriction.DeclaredOnly) as PropertySpec;
7168 prop = (Property)ps.MemberDefinition;
7171 var spec = prop.BackingField;
7175 if (rc.IsStatic != spec.IsStatic)
7178 if (!spec.IsStatic && (!(InstanceExpression is This) || InstanceExpression is BaseThis))
7181 backing_field = new FieldExpr (prop.BackingField, loc);
7182 backing_field.ResolveLValue (rc, rhs);
7186 public void SetBackingFieldAssigned (FlowAnalysisContext fc)
7188 if (backing_field != null) {
7189 backing_field.SetFieldAssigned (fc);
7193 if (!IsAutoPropertyAccess)
7196 var prop = best_candidate.MemberDefinition as Property;
7197 if (prop != null && prop.BackingField != null) {
7198 bool lvalue_instance = best_candidate.DeclaringType.IsStruct;
7199 if (lvalue_instance) {
7200 var var = InstanceExpression as IVariableReference;
7201 if (var != null && var.VariableInfo != null) {
7202 fc.SetStructFieldAssigned (var.VariableInfo, prop.BackingField.Name);
7208 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
7210 Error_TypeArgumentsCannotBeUsed (ec, "property", GetSignatureForError (), loc);
7214 abstract class PropertyOrIndexerExpr<T> : MemberExpr, IDynamicAssign where T : PropertySpec
7216 // getter and setter can be different for base calls
7217 MethodSpec getter, setter;
7218 protected T best_candidate;
7220 protected LocalTemporary temp;
7221 protected bool emitting_compound_assignment;
7222 protected bool has_await_arguments;
7224 protected PropertyOrIndexerExpr (Location l)
7231 protected abstract Arguments Arguments { get; set; }
7233 public MethodSpec Getter {
7242 public MethodSpec Setter {
7253 protected override Expression DoResolve (ResolveContext ec)
7255 if (eclass == ExprClass.Unresolved) {
7256 ResolveConditionalAccessReceiver (ec);
7258 var expr = OverloadResolve (ec, null);
7263 using (ec.With (ResolveContext.Options.DontSetConditionalAccessReceiver, conditional_access_receiver))
7264 return expr.Resolve (ec);
7267 if (conditional_access_receiver) {
7268 type = LiftMemberType (ec, type);
7272 if (!ResolveGetter (ec))
7278 public override Expression DoResolveLValue (ResolveContext rc, Expression right_side)
7280 if (HasConditionalAccess ())
7281 Error_NullPropagatingLValue (rc);
7283 if (right_side == EmptyExpression.OutAccess) {
7284 // TODO: best_candidate can be null at this point
7285 INamedBlockVariable variable = null;
7286 if (best_candidate != null && rc.CurrentBlock.ParametersBlock.TopBlock.GetLocalName (best_candidate.Name, rc.CurrentBlock, ref variable) && variable is Linq.RangeVariable) {
7287 rc.Report.Error (1939, loc, "A range variable `{0}' may not be passes as `ref' or `out' parameter",
7288 best_candidate.Name);
7290 right_side.DoResolveLValue (rc, this);
7295 if (eclass == ExprClass.Unresolved) {
7296 var expr = OverloadResolve (rc, right_side);
7301 return expr.ResolveLValue (rc, right_side);
7303 ResolveInstanceExpression (rc, right_side);
7306 if (!best_candidate.HasSet) {
7307 if (ResolveAutopropertyAssignment (rc, right_side))
7310 rc.Report.Error (200, loc, "Property or indexer `{0}' cannot be assigned to (it is read-only)",
7311 GetSignatureForError ());
7315 if (!best_candidate.Set.IsAccessible (rc) || !best_candidate.Set.DeclaringType.IsAccessible (rc)) {
7316 if (best_candidate.HasDifferentAccessibility) {
7317 rc.Report.SymbolRelatedToPreviousError (best_candidate.Set);
7318 rc.Report.Error (272, loc, "The property or indexer `{0}' cannot be used in this context because the set accessor is inaccessible",
7319 GetSignatureForError ());
7321 rc.Report.SymbolRelatedToPreviousError (best_candidate.Set);
7322 ErrorIsInaccesible (rc, best_candidate.GetSignatureForError (), loc);
7326 if (best_candidate.HasDifferentAccessibility)
7327 CheckProtectedMemberAccess (rc, best_candidate.Set);
7329 setter = CandidateToBaseOverride (rc, best_candidate.Set);
7333 void EmitConditionalAccess (EmitContext ec, ref CallEmitter call, MethodSpec method, Arguments arguments)
7335 var ca = ec.ConditionalAccess;
7336 ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
7338 call.Emit (ec, method, arguments, loc);
7340 ec.CloseConditionalAccess (method.ReturnType != type && type.IsNullableType ? type : null);
7341 ec.ConditionalAccess = ca;
7345 // Implements the IAssignMethod interface for assignments
7347 public virtual void Emit (EmitContext ec, bool leave_copy)
7349 var call = new CallEmitter ();
7350 call.ConditionalAccess = ConditionalAccess;
7351 call.InstanceExpression = InstanceExpression;
7352 if (has_await_arguments)
7353 call.HasAwaitArguments = true;
7355 call.DuplicateArguments = emitting_compound_assignment;
7357 if (conditional_access_receiver)
7358 EmitConditionalAccess (ec, ref call, Getter, Arguments);
7360 call.Emit (ec, Getter, Arguments, loc);
7362 if (call.HasAwaitArguments) {
7363 InstanceExpression = call.InstanceExpression;
7364 Arguments = call.EmittedArguments;
7365 has_await_arguments = true;
7369 ec.Emit (OpCodes.Dup);
7370 temp = new LocalTemporary (Type);
7375 public abstract void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound);
7377 public override void Emit (EmitContext ec)
7382 protected override FieldExpr EmitToFieldSource (EmitContext ec)
7384 has_await_arguments = true;
7389 public abstract SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source);
7391 protected abstract Expression OverloadResolve (ResolveContext rc, Expression right_side);
7393 bool ResolveGetter (ResolveContext rc)
7395 if (!best_candidate.HasGet) {
7396 if (InstanceExpression != EmptyExpression.Null) {
7397 rc.Report.SymbolRelatedToPreviousError (best_candidate);
7398 rc.Report.Error (154, loc, "The property or indexer `{0}' cannot be used in this context because it lacks the `get' accessor",
7399 best_candidate.GetSignatureForError ());
7402 } else if (!best_candidate.Get.IsAccessible (rc) || !best_candidate.Get.DeclaringType.IsAccessible (rc)) {
7403 if (best_candidate.HasDifferentAccessibility) {
7404 rc.Report.SymbolRelatedToPreviousError (best_candidate.Get);
7405 rc.Report.Error (271, loc, "The property or indexer `{0}' cannot be used in this context because the get accessor is inaccessible",
7406 TypeManager.CSharpSignature (best_candidate));
7408 rc.Report.SymbolRelatedToPreviousError (best_candidate.Get);
7409 ErrorIsInaccesible (rc, best_candidate.Get.GetSignatureForError (), loc);
7413 if (best_candidate.HasDifferentAccessibility) {
7414 CheckProtectedMemberAccess (rc, best_candidate.Get);
7417 getter = CandidateToBaseOverride (rc, best_candidate.Get);
7421 protected virtual bool ResolveAutopropertyAssignment (ResolveContext rc, Expression rhs)
7428 /// Fully resolved expression that evaluates to an Event
7430 public class EventExpr : MemberExpr, IAssignMethod
7432 readonly EventSpec spec;
7435 public EventExpr (EventSpec spec, Location loc)
7443 protected override TypeSpec DeclaringType {
7445 return spec.DeclaringType;
7449 public override string Name {
7455 public override bool IsInstance {
7457 return !spec.IsStatic;
7461 public override bool IsStatic {
7463 return spec.IsStatic;
7467 public override string KindName {
7468 get { return "event"; }
7471 public MethodSpec Operator {
7479 public override MemberExpr ResolveMemberAccess (ResolveContext ec, Expression left, SimpleName original)
7482 // If the event is local to this class and we are not lhs of +=/-= we transform ourselves into a FieldExpr
7484 if (!ec.HasSet (ResolveContext.Options.CompoundAssignmentScope)) {
7485 if (spec.BackingField != null &&
7486 (spec.DeclaringType == ec.CurrentType || TypeManager.IsNestedChildOf (ec.CurrentType, spec.DeclaringType.MemberDefinition))) {
7488 spec.MemberDefinition.SetIsUsed ();
7490 spec.CheckObsoleteness (ec, loc);
7492 if ((spec.Modifiers & (Modifiers.ABSTRACT | Modifiers.EXTERN)) != 0)
7493 Error_AssignmentEventOnly (ec);
7495 FieldExpr ml = new FieldExpr (spec.BackingField, loc);
7497 InstanceExpression = null;
7499 return ml.ResolveMemberAccess (ec, left, original);
7503 return base.ResolveMemberAccess (ec, left, original);
7506 public override Expression CreateExpressionTree (ResolveContext ec)
7508 throw new NotSupportedException ("ET");
7511 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
7513 if (right_side == EmptyExpression.EventAddition) {
7514 op = spec.AccessorAdd;
7515 } else if (right_side == EmptyExpression.EventSubtraction) {
7516 op = spec.AccessorRemove;
7520 Error_AssignmentEventOnly (ec);
7524 if (HasConditionalAccess ())
7525 Error_NullPropagatingLValue (ec);
7527 op = CandidateToBaseOverride (ec, op);
7531 protected override Expression DoResolve (ResolveContext ec)
7533 eclass = ExprClass.EventAccess;
7534 type = spec.MemberType;
7536 ResolveInstanceExpression (ec, null);
7538 if (!ec.HasSet (ResolveContext.Options.CompoundAssignmentScope)) {
7539 Error_AssignmentEventOnly (ec);
7542 DoBestMemberChecks (ec, spec);
7546 public override void Emit (EmitContext ec)
7548 throw new NotSupportedException ();
7549 //Error_CannotAssign ();
7552 #region IAssignMethod Members
7554 public void Emit (EmitContext ec, bool leave_copy)
7556 throw new NotImplementedException ();
7559 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
7561 if (leave_copy || !isCompound)
7562 throw new NotImplementedException ("EventExpr::EmitAssign");
7564 Arguments args = new Arguments (1);
7565 args.Add (new Argument (source));
7567 // TODO: Wrong, needs receiver
7568 // if (NullShortCircuit) {
7569 // ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
7572 var call = new CallEmitter ();
7573 call.InstanceExpression = InstanceExpression;
7574 call.ConditionalAccess = ConditionalAccess;
7575 call.EmitStatement (ec, op, args, loc);
7577 // if (NullShortCircuit)
7578 // ec.CloseConditionalAccess (null);
7583 void Error_AssignmentEventOnly (ResolveContext ec)
7585 if (spec.DeclaringType == ec.CurrentType || TypeManager.IsNestedChildOf (ec.CurrentType, spec.DeclaringType.MemberDefinition)) {
7586 ec.Report.Error (79, loc,
7587 "The event `{0}' can only appear on the left hand side of `+=' or `-=' operator",
7588 GetSignatureForError ());
7590 ec.Report.Error (70, loc,
7591 "The event `{0}' can only appear on the left hand side of += or -= when used outside of the type `{1}'",
7592 GetSignatureForError (), spec.DeclaringType.GetSignatureForError ());
7596 protected override void Error_CannotCallAbstractBase (ResolveContext rc, string name)
7598 name = name.Substring (0, name.LastIndexOf ('.'));
7599 base.Error_CannotCallAbstractBase (rc, name);
7602 public override string GetSignatureForError ()
7604 return TypeManager.CSharpSignature (spec);
7607 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
7609 Error_TypeArgumentsCannotBeUsed (ec, "event", GetSignatureForError (), loc);
7613 public class TemporaryVariableReference : VariableReference
7615 public class Declarator : Statement
7617 TemporaryVariableReference variable;
7619 public Declarator (TemporaryVariableReference variable)
7621 this.variable = variable;
7625 protected override void DoEmit (EmitContext ec)
7627 variable.li.CreateBuilder (ec);
7630 public override void Emit (EmitContext ec)
7632 // Don't create sequence point
7636 protected override bool DoFlowAnalysis (FlowAnalysisContext fc)
7641 protected override void CloneTo (CloneContext clonectx, Statement target)
7649 public TemporaryVariableReference (LocalVariable li, Location loc)
7652 this.type = li.Type;
7656 public override bool IsLockedByStatement {
7664 public LocalVariable LocalInfo {
7670 public static TemporaryVariableReference Create (TypeSpec type, Block block, Location loc, bool writeToSymbolFile = false)
7672 var li = LocalVariable.CreateCompilerGenerated (type, block, loc, writeToSymbolFile);
7673 return new TemporaryVariableReference (li, loc);
7676 protected override Expression DoResolve (ResolveContext ec)
7678 eclass = ExprClass.Variable;
7681 // Don't capture temporary variables except when using
7682 // state machine redirection and block yields
7684 if (ec.CurrentAnonymousMethod is StateMachineInitializer &&
7685 (ec.CurrentBlock.Explicit.HasYield || ec.CurrentBlock.Explicit.HasAwait) &&
7686 ec.IsVariableCapturingRequired) {
7687 AnonymousMethodStorey storey = li.Block.Explicit.CreateAnonymousMethodStorey (ec);
7688 storey.CaptureLocalVariable (ec, li);
7694 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
7696 return Resolve (ec);
7699 public override void Emit (EmitContext ec)
7701 li.CreateBuilder (ec);
7706 public void EmitAssign (EmitContext ec, Expression source)
7708 li.CreateBuilder (ec);
7710 EmitAssign (ec, source, false, false);
7713 public override HoistedVariable GetHoistedVariable (AnonymousExpression ae)
7715 return li.HoistedVariant;
7718 public override bool IsFixed {
7719 get { return true; }
7722 public override bool IsRef {
7723 get { return false; }
7726 public override string Name {
7727 get { throw new NotImplementedException (); }
7730 public override void SetHasAddressTaken ()
7732 throw new NotImplementedException ();
7735 protected override ILocalVariable Variable {
7739 public override VariableInfo VariableInfo {
7740 get { return null; }
7745 /// Handles `var' contextual keyword; var becomes a keyword only
7746 /// if no type called var exists in a variable scope
7748 class VarExpr : SimpleName
7750 public VarExpr (Location loc)
7755 public bool InferType (ResolveContext ec, Expression right_side)
7758 throw new InternalErrorException ("An implicitly typed local variable could not be redefined");
7760 type = right_side.Type;
7761 if (type == InternalType.NullLiteral || type.Kind == MemberKind.Void || type == InternalType.AnonymousMethod || type == InternalType.MethodGroup) {
7762 ec.Report.Error (815, loc,
7763 "An implicitly typed local variable declaration cannot be initialized with `{0}'",
7764 type.GetSignatureForError ());
7765 type = InternalType.ErrorType;
7769 eclass = ExprClass.Variable;
7773 protected override void Error_TypeOrNamespaceNotFound (IMemberContext ec)
7775 if (ec.Module.Compiler.Settings.Version < LanguageVersion.V_3)
7776 base.Error_TypeOrNamespaceNotFound (ec);
7778 ec.Module.Compiler.Report.Error (825, loc, "The contextual keyword `var' may only appear within a local variable declaration");