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
131 public ExprClass eclass;
132 protected TypeSpec type;
133 protected Location loc;
135 public TypeSpec Type {
137 set { type = value; }
140 public virtual bool IsSideEffectFree {
146 public Location Location {
150 public virtual bool IsNull {
157 // Used to workaround parser limitation where we cannot get
158 // start of statement expression location
160 public virtual Location StartLocation {
166 public virtual MethodGroupExpr CanReduceLambda (AnonymousMethodBody body)
169 // Return method-group expression when the expression can be used as
170 // lambda replacement. A good example is array sorting where instead of
173 // Array.Sort (s, (a, b) => String.Compare (a, b));
175 // we can use method group directly
177 // Array.Sort (s, String.Compare);
179 // Correct overload will be used because we do the reduction after
180 // best candidate was found.
186 // Returns true when the expression during Emit phase breaks stack
187 // by using await expression
189 public virtual bool ContainsEmitWithAwait ()
195 /// Performs semantic analysis on the Expression
199 /// The Resolve method is invoked to perform the semantic analysis
202 /// The return value is an expression (it can be the
203 /// same expression in some cases) or a new
204 /// expression that better represents this node.
206 /// For example, optimizations of Unary (LiteralInt)
207 /// would return a new LiteralInt with a negated
210 /// If there is an error during semantic analysis,
211 /// then an error should be reported (using Report)
212 /// and a null value should be returned.
214 /// There are two side effects expected from calling
215 /// Resolve(): the the field variable "eclass" should
216 /// be set to any value of the enumeration
217 /// `ExprClass' and the type variable should be set
218 /// to a valid type (this is the type of the
221 protected abstract Expression DoResolve (ResolveContext rc);
223 public virtual Expression DoResolveLValue (ResolveContext rc, Expression right_side)
229 // This is used if the expression should be resolved as a type or namespace name.
230 // the default implementation fails.
232 public virtual TypeSpec ResolveAsType (IMemberContext mc, bool allowUnboundTypeArguments = false)
234 var rc = mc as ResolveContext ?? new ResolveContext (mc);
235 Expression e = Resolve (rc);
237 e.Error_UnexpectedKind (rc, ResolveFlags.Type, loc);
242 public static void ErrorIsInaccesible (IMemberContext rc, string member, Location loc)
244 rc.Module.Compiler.Report.Error (122, loc, "`{0}' is inaccessible due to its protection level", member);
247 public void Error_ExpressionMustBeConstant (ResolveContext rc, Location loc, string e_name)
249 rc.Report.Error (133, loc, "The expression being assigned to `{0}' must be constant", e_name);
252 public void Error_ConstantCanBeInitializedWithNullOnly (ResolveContext rc, TypeSpec type, Location loc, string name)
254 rc.Report.Error (134, loc, "A constant `{0}' of reference type `{1}' can only be initialized with null",
255 name, type.GetSignatureForError ());
258 protected virtual void Error_InvalidExpressionStatement (Report report, Location loc)
260 report.Error (201, loc, "Only assignment, call, increment, decrement, await, and new object expressions can be used as a statement");
263 public void Error_InvalidExpressionStatement (BlockContext bc)
265 Error_InvalidExpressionStatement (bc.Report, loc);
268 public void Error_InvalidExpressionStatement (Report report)
270 Error_InvalidExpressionStatement (report, loc);
273 public static void Error_VoidInvalidInTheContext (Location loc, Report Report)
275 Report.Error (1547, loc, "Keyword `void' cannot be used in this context");
278 public virtual void Error_ValueCannotBeConverted (ResolveContext ec, TypeSpec target, bool expl)
280 Error_ValueCannotBeConvertedCore (ec, loc, target, expl);
283 protected void Error_ValueCannotBeConvertedCore (ResolveContext ec, Location loc, TypeSpec target, bool expl)
285 // The error was already reported as CS1660
286 if (type == InternalType.AnonymousMethod)
289 if (type == InternalType.ErrorType || target == InternalType.ErrorType)
292 if (type.MemberDefinition.DeclaringAssembly.IsMissing ||
293 target.MemberDefinition.DeclaringAssembly.IsMissing)
296 string from_type = type.GetSignatureForError ();
297 string to_type = target.GetSignatureForError ();
298 if (from_type == to_type) {
299 from_type = type.GetSignatureForErrorIncludingAssemblyName ();
300 to_type = target.GetSignatureForErrorIncludingAssemblyName ();
304 ec.Report.Error (30, loc, "Cannot convert type `{0}' to `{1}'",
309 ec.Report.DisableReporting ();
310 bool expl_exists = Convert.ExplicitConversion (ec, this, target, Location.Null) != null;
311 ec.Report.EnableReporting ();
314 ec.Report.Error (266, loc,
315 "Cannot implicitly convert type `{0}' to `{1}'. An explicit conversion exists (are you missing a cast?)",
318 ec.Report.Error (29, loc, "Cannot implicitly convert type `{0}' to `{1}'",
323 public void Error_TypeArgumentsCannotBeUsed (IMemberContext context, MemberSpec member, Location loc)
325 // Better message for possible generic expressions
326 if (member != null && (member.Kind & MemberKind.GenericMask) != 0) {
327 var report = context.Module.Compiler.Report;
328 report.SymbolRelatedToPreviousError (member);
329 if (member is TypeSpec)
330 member = ((TypeSpec) member).GetDefinition ();
332 member = ((MethodSpec) member).GetGenericMethodDefinition ();
334 string name = member.Kind == MemberKind.Method ? "method" : "type";
335 if (member.IsGeneric) {
336 report.Error (305, loc, "Using the generic {0} `{1}' requires `{2}' type argument(s)",
337 name, member.GetSignatureForError (), member.Arity.ToString ());
339 report.Error (308, loc, "The non-generic {0} `{1}' cannot be used with the type arguments",
340 name, member.GetSignatureForError ());
343 Error_TypeArgumentsCannotBeUsed (context, ExprClassName, GetSignatureForError (), loc);
347 public static void Error_TypeArgumentsCannotBeUsed (IMemberContext context, string exprType, string name, Location loc)
349 context.Module.Compiler.Report.Error (307, loc, "The {0} `{1}' cannot be used with type arguments",
353 public virtual void Error_TypeDoesNotContainDefinition (ResolveContext ec, TypeSpec type, string name)
355 Error_TypeDoesNotContainDefinition (ec, loc, type, name);
358 public static void Error_TypeDoesNotContainDefinition (ResolveContext ec, Location loc, TypeSpec type, string name)
360 ec.Report.SymbolRelatedToPreviousError (type);
361 ec.Report.Error (117, loc, "`{0}' does not contain a definition for `{1}'",
362 type.GetSignatureForError (), name);
365 public virtual void Error_ValueAssignment (ResolveContext rc, Expression rhs)
367 if (rhs == EmptyExpression.LValueMemberAccess || rhs == EmptyExpression.LValueMemberOutAccess) {
368 // Already reported as CS1612
369 } else if (rhs == EmptyExpression.OutAccess) {
370 rc.Report.Error (1510, loc, "A ref or out argument must be an assignable variable");
372 rc.Report.Error (131, loc, "The left-hand side of an assignment must be a variable, a property or an indexer");
376 protected void Error_VoidPointerOperation (ResolveContext rc)
378 rc.Report.Error (242, loc, "The operation in question is undefined on void pointers");
381 public static void Warning_UnreachableExpression (ResolveContext rc, Location loc)
383 rc.Report.Warning (429, 4, loc, "Unreachable expression code detected");
386 public ResolveFlags ExprClassToResolveFlags {
390 case ExprClass.Namespace:
391 return ResolveFlags.Type;
393 case ExprClass.MethodGroup:
394 return ResolveFlags.MethodGroup;
396 case ExprClass.TypeParameter:
397 return ResolveFlags.TypeParameter;
399 case ExprClass.Value:
400 case ExprClass.Variable:
401 case ExprClass.PropertyAccess:
402 case ExprClass.EventAccess:
403 case ExprClass.IndexerAccess:
404 return ResolveFlags.VariableOrValue;
407 throw new InternalErrorException (loc.ToString () + " " + GetType () + " ExprClass is Invalid after resolve");
413 // Implements identical simple name and type-name resolution
415 public Expression ProbeIdenticalTypeName (ResolveContext rc, Expression left, SimpleName name)
418 if (t.Kind == MemberKind.InternalCompilerType || t is ElementTypeSpec || t.Arity > 0)
421 // 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
422 // a constant, field, property, local variable, or parameter with the same type as the meaning of E as a type-name
424 if (left is MemberExpr || left is VariableReference) {
425 var identical_type = rc.LookupNamespaceOrType (name.Name, 0, LookupMode.Probing, loc) as TypeExpr;
426 if (identical_type != null && identical_type.Type == left.Type)
427 return identical_type;
433 public virtual string GetSignatureForError ()
435 return type.GetDefinition ().GetSignatureForError ();
438 public static bool IsNeverNull (Expression expr)
440 if (expr is This || expr is New || expr is ArrayCreation || expr is DelegateCreation || expr is ConditionalMemberAccess)
443 var c = expr as Constant;
447 var tc = expr as TypeCast;
449 return IsNeverNull (tc.Child);
454 protected static bool IsNullPropagatingValid (TypeSpec type)
457 case MemberKind.Struct:
458 return type.IsNullableType;
459 case MemberKind.Enum:
460 case MemberKind.Void:
461 case MemberKind.PointerType:
463 case MemberKind.InternalCompilerType:
464 return type.BuiltinType == BuiltinTypeSpec.Type.Dynamic;
465 case MemberKind.TypeParameter:
466 return !((TypeParameterSpec) type).IsValueType;
472 public virtual bool HasConditionalAccess ()
477 protected TypeSpec LiftMemberType (ResolveContext rc, TypeSpec type)
479 var tps = type as TypeParameterSpec;
480 if (tps != null && !(tps.IsReferenceType || tps.IsValueType)) {
481 Error_OperatorCannotBeApplied (rc, loc, "?", type);
484 return TypeSpec.IsValueType (type) && !type.IsNullableType ?
485 Nullable.NullableInfo.MakeType (rc.Module, type) :
490 /// Resolves an expression and performs semantic analysis on it.
494 /// Currently Resolve wraps DoResolve to perform sanity
495 /// checking and assertion checking on what we expect from Resolve.
497 public Expression Resolve (ResolveContext ec, ResolveFlags flags)
499 if (eclass != ExprClass.Unresolved) {
500 if ((flags & ExprClassToResolveFlags) == 0) {
501 Error_UnexpectedKind (ec, flags, loc);
515 if ((flags & e.ExprClassToResolveFlags) == 0) {
516 e.Error_UnexpectedKind (ec, flags, loc);
521 throw new InternalErrorException ("Expression `{0}' didn't set its type in DoResolve", e.GetType ());
524 } catch (Exception ex) {
525 if (loc.IsNull || ec.Module.Compiler.Settings.BreakOnInternalError || ex is CompletionResult || ec.Report.IsDisabled || ex is FatalException ||
526 ec.Report.Printer is NullReportPrinter)
529 ec.Report.Error (584, loc, "Internal compiler error: {0}", ex.Message);
530 return ErrorExpression.Instance; // TODO: Add location
535 /// Resolves an expression and performs semantic analysis on it.
537 public Expression Resolve (ResolveContext rc)
539 return Resolve (rc, ResolveFlags.VariableOrValue | ResolveFlags.MethodGroup);
543 /// Resolves an expression for LValue assignment
547 /// Currently ResolveLValue wraps DoResolveLValue to perform sanity
548 /// checking and assertion checking on what we expect from Resolve
550 public Expression ResolveLValue (ResolveContext ec, Expression right_side)
552 int errors = ec.Report.Errors;
553 bool out_access = right_side == EmptyExpression.OutAccess;
555 Expression e = DoResolveLValue (ec, right_side);
557 if (e != null && out_access && !(e is IMemoryLocation)) {
558 // FIXME: There's no problem with correctness, the 'Expr = null' handles that.
559 // Enabling this 'throw' will "only" result in deleting useless code elsewhere,
561 //throw new InternalErrorException ("ResolveLValue didn't return an IMemoryLocation: " +
562 // e.GetType () + " " + e.GetSignatureForError ());
567 if (errors == ec.Report.Errors) {
568 Error_ValueAssignment (ec, right_side);
573 if (e.eclass == ExprClass.Unresolved)
574 throw new Exception ("Expression " + e + " ExprClass is Invalid after resolve");
576 if ((e.type == null) && !(e is GenericTypeExpr))
577 throw new Exception ("Expression " + e + " did not set its type after Resolve");
582 public Constant ResolveLabelConstant (ResolveContext rc)
584 var expr = Resolve (rc);
588 Constant c = expr as Constant;
590 if (expr.type != InternalType.ErrorType)
591 rc.Report.Error (150, expr.StartLocation, "A constant value is expected");
599 public virtual void EncodeAttributeValue (IMemberContext rc, AttributeEncoder enc, TypeSpec targetType, TypeSpec parameterType)
601 if (Attribute.IsValidArgumentType (parameterType)) {
602 rc.Module.Compiler.Report.Error (182, loc,
603 "An attribute argument must be a constant expression, typeof expression or array creation expression");
605 rc.Module.Compiler.Report.Error (181, loc,
606 "Attribute constructor parameter has type `{0}', which is not a valid attribute parameter type",
607 targetType.GetSignatureForError ());
612 /// Emits the code for the expression
616 /// The Emit method is invoked to generate the code
617 /// for the expression.
619 public abstract void Emit (EmitContext ec);
622 // Emit code to branch to @target if this expression is equivalent to @on_true.
623 // The default implementation is to emit the value, and then emit a brtrue or brfalse.
624 // Subclasses can provide more efficient implementations, but those MUST be equivalent,
625 // including the use of conditional branches. Note also that a branch MUST be emitted
626 public virtual void EmitBranchable (EmitContext ec, Label target, bool on_true)
629 ec.Emit (on_true ? OpCodes.Brtrue : OpCodes.Brfalse, target);
632 // Emit this expression for its side effects, not for its value.
633 // The default implementation is to emit the value, and then throw it away.
634 // Subclasses can provide more efficient implementations, but those MUST be equivalent
635 public virtual void EmitSideEffect (EmitContext ec)
638 ec.Emit (OpCodes.Pop);
642 // Emits the expression into temporary field variable. The method
643 // should be used for await expressions only
645 public virtual Expression EmitToField (EmitContext ec)
648 // This is the await prepare Emit method. When emitting code like
649 // a + b we emit code like
655 // For await a + await b we have to interfere the flow to keep the
656 // stack clean because await yields from the expression. The emit
659 // a = a.EmitToField () // a is changed to temporary field access
660 // b = b.EmitToField ()
666 // The idea is to emit expression and leave the stack empty with
667 // result value still available.
669 // Expressions should override this default implementation when
670 // optimized version can be provided (e.g. FieldExpr)
673 // We can optimize for side-effect free expressions, they can be
674 // emitted out of order
676 if (IsSideEffectFree)
679 bool needs_temporary = ContainsEmitWithAwait ();
680 if (!needs_temporary)
683 // Emit original code
684 var field = EmitToFieldSource (ec);
687 // Store the result to temporary field when we
688 // cannot load `this' directly
690 field = ec.GetTemporaryField (type);
691 if (needs_temporary) {
693 // Create temporary local (we cannot load `this' before Emit)
695 var temp = ec.GetTemporaryLocal (type);
696 ec.Emit (OpCodes.Stloc, temp);
699 ec.Emit (OpCodes.Ldloc, temp);
700 field.EmitAssignFromStack (ec);
702 ec.FreeTemporaryLocal (temp, type);
704 field.EmitAssignFromStack (ec);
711 protected virtual FieldExpr EmitToFieldSource (EmitContext ec)
714 // Default implementation calls Emit method
720 protected static void EmitExpressionsList (EmitContext ec, List<Expression> expressions)
722 if (ec.HasSet (BuilderContext.Options.AsyncBody)) {
723 bool contains_await = false;
725 for (int i = 1; i < expressions.Count; ++i) {
726 if (expressions[i].ContainsEmitWithAwait ()) {
727 contains_await = true;
732 if (contains_await) {
733 for (int i = 0; i < expressions.Count; ++i) {
734 expressions[i] = expressions[i].EmitToField (ec);
739 for (int i = 0; i < expressions.Count; ++i) {
740 expressions[i].Emit (ec);
745 /// Protected constructor. Only derivate types should
746 /// be able to be created
749 protected Expression ()
754 /// Returns a fully formed expression after a MemberLookup
757 static Expression ExprClassFromMemberInfo (MemberSpec spec, Location loc)
759 if (spec is EventSpec)
760 return new EventExpr ((EventSpec) spec, loc);
761 if (spec is ConstSpec)
762 return new ConstantExpr ((ConstSpec) spec, loc);
763 if (spec is FieldSpec)
764 return new FieldExpr ((FieldSpec) spec, loc);
765 if (spec is PropertySpec)
766 return new PropertyExpr ((PropertySpec) spec, loc);
767 if (spec is TypeSpec)
768 return new TypeExpression (((TypeSpec) spec), loc);
773 public static MethodSpec ConstructorLookup (ResolveContext rc, TypeSpec type, ref Arguments args, Location loc)
775 var ctors = MemberCache.FindMembers (type, Constructor.ConstructorName, true);
778 case MemberKind.Struct:
779 // Every struct has implicit default constructor if not provided by user
783 rc.Report.SymbolRelatedToPreviousError (type);
784 // Report meaningful error for struct as they always have default ctor in C# context
785 OverloadResolver.Error_ConstructorMismatch (rc, type, args == null ? 0 : args.Count, loc);
787 case MemberKind.MissingType:
788 case MemberKind.InternalCompilerType:
789 // LAMESPEC: dynamic is not really object
790 // if (type.BuiltinType == BuiltinTypeSpec.Type.Object)
794 rc.Report.SymbolRelatedToPreviousError (type);
795 rc.Report.Error (143, loc, "The class `{0}' has no constructors defined",
796 type.GetSignatureForError ());
803 if (args == null && type.IsStruct) {
804 bool includes_empty = false;
805 foreach (MethodSpec ctor in ctors) {
806 if (ctor.Parameters.IsEmpty) {
807 includes_empty = true;
815 var r = new OverloadResolver (ctors, OverloadResolver.Restrictions.NoBaseMembers, loc);
816 if (!rc.HasSet (ResolveContext.Options.BaseInitializer)) {
817 r.InstanceQualifier = new ConstructorInstanceQualifier (type);
820 return r.ResolveMember<MethodSpec> (rc, ref args);
824 public enum MemberLookupRestrictions
830 EmptyArguments = 1 << 4,
831 IgnoreArity = 1 << 5,
832 IgnoreAmbiguity = 1 << 6,
833 NameOfExcluded = 1 << 7,
834 DontSetConditionalAccess = 1 << 8
838 // Lookup type `queried_type' for code in class `container_type' with a qualifier of
839 // `qualifier_type' or null to lookup members in the current class.
841 public static Expression MemberLookup (IMemberContext rc, bool errorMode, TypeSpec queried_type, string name, int arity, MemberLookupRestrictions restrictions, Location loc)
843 var members = MemberCache.FindMembers (queried_type, name, false);
845 if (members != null) {
848 expr = MemberLookupToExpression (rc, members, errorMode, queried_type, name, arity, restrictions, loc);
852 if (members [0].DeclaringType.BaseType == null)
855 members = MemberCache.FindMembers (members [0].DeclaringType.BaseType, name, false);
856 } while (members != null);
859 var tps = queried_type as TypeParameterSpec;
861 members = MemberCache.FindInterfaceMembers (tps, name);
863 return MemberLookupToExpression (rc, members, errorMode, queried_type, name, arity, restrictions, loc);
869 public static Expression MemberLookupToExpression (IMemberContext rc, IList<MemberSpec> members, bool errorMode, TypeSpec queried_type, string name, int arity, MemberLookupRestrictions restrictions, Location loc)
871 MemberSpec non_method = null;
872 MemberSpec ambig_non_method = null;
874 for (int i = 0; i < members.Count; ++i) {
875 var member = members [i];
877 // HACK: for events because +=/-= can appear at same class only, should use OverrideToBase there
878 if ((member.Modifiers & Modifiers.OVERRIDE) != 0 && member.Kind != MemberKind.Event)
881 if ((member.Modifiers & Modifiers.BACKING_FIELD) != 0 || member.Kind == MemberKind.Operator)
884 if ((arity > 0 || (restrictions & MemberLookupRestrictions.ExactArity) != 0) && member.Arity != arity)
888 if (!member.IsAccessible (rc))
892 // With runtime binder we can have a situation where queried type is inaccessible
893 // because it came via dynamic object, the check about inconsisted accessibility
894 // had no effect as the type was unknown during compilation
897 // private class N { }
899 // public dynamic Foo ()
905 if (rc.Module.Compiler.IsRuntimeBinder && !member.DeclaringType.IsAccessible (rc))
909 if ((restrictions & MemberLookupRestrictions.InvocableOnly) != 0) {
910 if (member is MethodSpec) {
911 return new MethodGroupExpr (members, queried_type, loc);
914 if (!Invocation.IsMemberInvocable (member))
918 if (non_method == null || member is MethodSpec || non_method.IsNotCSharpCompatible) {
920 } else if (!errorMode && !member.IsNotCSharpCompatible) {
922 // Interface members that are hidden by class members are removed from the set when T is a type parameter and
923 // T has both an effective base class other than object and a non-empty effective interface set.
925 // The spec has more complex rules but we simply remove all members declared in an interface declaration.
927 var tps = queried_type as TypeParameterSpec;
928 if (tps != null && tps.HasTypeConstraint) {
929 if (non_method.DeclaringType.IsClass && member.DeclaringType.IsInterface)
932 if (non_method.DeclaringType.IsInterface && member.DeclaringType.IsInterface) {
938 ambig_non_method = member;
942 if (non_method != null) {
943 if (ambig_non_method != null && rc != null && (restrictions & MemberLookupRestrictions.IgnoreAmbiguity) == 0) {
944 var report = rc.Module.Compiler.Report;
945 report.SymbolRelatedToPreviousError (non_method);
946 report.SymbolRelatedToPreviousError (ambig_non_method);
947 report.Error (229, loc, "Ambiguity between `{0}' and `{1}'",
948 non_method.GetSignatureForError (), ambig_non_method.GetSignatureForError ());
951 if (non_method is MethodSpec)
952 return new MethodGroupExpr (members, queried_type, loc);
954 return ExprClassFromMemberInfo (non_method, loc);
960 protected static void Error_NamedArgument (NamedArgument na, Report Report)
962 Report.Error (1742, na.Location, "An element access expression cannot use named argument");
965 protected virtual void Error_NegativeArrayIndex (ResolveContext ec, Location loc)
967 throw new NotImplementedException ();
970 public virtual void Error_OperatorCannotBeApplied (ResolveContext rc, Location loc, string oper, TypeSpec t)
972 if (t == InternalType.ErrorType)
975 rc.Report.Error (23, loc, "The `{0}' operator cannot be applied to operand of type `{1}'",
976 oper, t.GetSignatureForError ());
979 protected void Error_PointerInsideExpressionTree (ResolveContext ec)
981 ec.Report.Error (1944, loc, "An expression tree cannot contain an unsafe pointer operation");
984 protected void Error_NullShortCircuitInsideExpressionTree (ResolveContext rc)
986 rc.Report.Error (8072, loc, "An expression tree cannot contain a null propagating operator");
989 protected void Error_NullPropagatingLValue (ResolveContext rc)
991 rc.Report.Error (-1030, loc, "The left-hand side of an assignment cannot contain a null propagating operator");
994 public virtual void FlowAnalysis (FlowAnalysisContext fc)
999 // Special version of flow analysis for expressions which can return different
1000 // on-true and on-false result. Used by &&, ||, ?: expressions
1002 public virtual void FlowAnalysisConditional (FlowAnalysisContext fc)
1005 fc.DefiniteAssignmentOnTrue = fc.DefiniteAssignmentOnFalse = fc.DefiniteAssignment;
1009 /// Returns an expression that can be used to invoke operator true
1010 /// on the expression if it exists.
1012 protected static Expression GetOperatorTrue (ResolveContext ec, Expression e, Location loc)
1014 return GetOperatorTrueOrFalse (ec, e, true, loc);
1018 /// Returns an expression that can be used to invoke operator false
1019 /// on the expression if it exists.
1021 protected static Expression GetOperatorFalse (ResolveContext ec, Expression e, Location loc)
1023 return GetOperatorTrueOrFalse (ec, e, false, loc);
1026 static Expression GetOperatorTrueOrFalse (ResolveContext ec, Expression e, bool is_true, Location loc)
1028 var op = is_true ? Operator.OpType.True : Operator.OpType.False;
1030 if (type.IsNullableType)
1031 type = Nullable.NullableInfo.GetUnderlyingType (type);
1033 var methods = MemberCache.GetUserOperator (type, op, false);
1034 if (methods == null)
1037 Arguments arguments = new Arguments (1);
1038 arguments.Add (new Argument (e));
1040 var res = new OverloadResolver (methods, OverloadResolver.Restrictions.BaseMembersIncluded | OverloadResolver.Restrictions.NoBaseMembers, loc);
1041 var oper = res.ResolveOperator (ec, ref arguments);
1046 return new UserOperatorCall (oper, arguments, null, loc);
1049 public virtual string ExprClassName
1053 case ExprClass.Unresolved:
1054 return "Unresolved";
1055 case ExprClass.Value:
1057 case ExprClass.Variable:
1059 case ExprClass.Namespace:
1061 case ExprClass.Type:
1063 case ExprClass.MethodGroup:
1064 return "method group";
1065 case ExprClass.PropertyAccess:
1066 return "property access";
1067 case ExprClass.EventAccess:
1068 return "event access";
1069 case ExprClass.IndexerAccess:
1070 return "indexer access";
1071 case ExprClass.Nothing:
1073 case ExprClass.TypeParameter:
1074 return "type parameter";
1076 throw new Exception ("Should not happen");
1081 /// Reports that we were expecting `expr' to be of class `expected'
1083 public static void Error_UnexpectedKind (IMemberContext ctx, Expression memberExpr, string expected, string was, Location loc)
1085 var name = memberExpr.GetSignatureForError ();
1087 ctx.Module.Compiler.Report.Error (118, loc, "`{0}' is a `{1}' but a `{2}' was expected", name, was, expected);
1090 public virtual void Error_UnexpectedKind (ResolveContext ec, ResolveFlags flags, Location loc)
1092 string [] valid = new string [4];
1095 if ((flags & ResolveFlags.VariableOrValue) != 0) {
1096 valid [count++] = "variable";
1097 valid [count++] = "value";
1100 if ((flags & ResolveFlags.Type) != 0)
1101 valid [count++] = "type";
1103 if ((flags & ResolveFlags.MethodGroup) != 0)
1104 valid [count++] = "method group";
1107 valid [count++] = "unknown";
1109 StringBuilder sb = new StringBuilder (valid [0]);
1110 for (int i = 1; i < count - 1; i++) {
1112 sb.Append (valid [i]);
1115 sb.Append ("' or `");
1116 sb.Append (valid [count - 1]);
1119 ec.Report.Error (119, loc,
1120 "Expression denotes a `{0}', where a `{1}' was expected", ExprClassName, sb.ToString ());
1123 public static void UnsafeError (ResolveContext ec, Location loc)
1125 UnsafeError (ec.Report, loc);
1128 public static void UnsafeError (Report Report, Location loc)
1130 Report.Error (214, loc, "Pointers and fixed size buffers may only be used in an unsafe context");
1134 // Converts `source' to an int, uint, long or ulong.
1136 protected Expression ConvertExpressionToArrayIndex (ResolveContext ec, Expression source, bool pointerArray = false)
1138 var btypes = ec.BuiltinTypes;
1140 if (source.type.BuiltinType == BuiltinTypeSpec.Type.Dynamic) {
1141 Arguments args = new Arguments (1);
1142 args.Add (new Argument (source));
1143 return new DynamicConversion (btypes.Int, CSharpBinderFlags.ConvertArrayIndex, args, source.loc).Resolve (ec);
1146 Expression converted;
1148 using (ec.Set (ResolveContext.Options.CheckedScope)) {
1149 converted = Convert.ImplicitConversion (ec, source, btypes.Int, source.loc);
1150 if (converted == null)
1151 converted = Convert.ImplicitConversion (ec, source, btypes.UInt, source.loc);
1152 if (converted == null)
1153 converted = Convert.ImplicitConversion (ec, source, btypes.Long, source.loc);
1154 if (converted == null)
1155 converted = Convert.ImplicitConversion (ec, source, btypes.ULong, source.loc);
1157 if (converted == null) {
1158 source.Error_ValueCannotBeConverted (ec, btypes.Int, false);
1167 // Only positive constants are allowed at compile time
1169 Constant c = converted as Constant;
1170 if (c != null && c.IsNegative)
1171 Error_NegativeArrayIndex (ec, source.loc);
1173 // No conversion needed to array index
1174 if (converted.Type.BuiltinType == BuiltinTypeSpec.Type.Int)
1177 return new ArrayIndexCast (converted, btypes.Int).Resolve (ec);
1180 public Expression MakePointerAccess (ResolveContext rc, TypeSpec type, Arguments args)
1182 if (args.Count != 1){
1183 rc.Report.Error (196, loc, "A pointer must be indexed by only one value");
1188 if (arg is NamedArgument)
1189 Error_NamedArgument ((NamedArgument) arg, rc.Report);
1191 var index = arg.Expr.Resolve (rc);
1195 index = ConvertExpressionToArrayIndex (rc, index, true);
1197 Expression p = new PointerArithmetic (Binary.Operator.Addition, this, index, type, loc);
1198 return new Indirection (p, loc);
1202 // Derived classes implement this method by cloning the fields that
1203 // could become altered during the Resolve stage
1205 // Only expressions that are created for the parser need to implement
1208 protected virtual void CloneTo (CloneContext clonectx, Expression target)
1210 throw new NotImplementedException (
1212 "CloneTo not implemented for expression {0}", this.GetType ()));
1216 // Clones an expression created by the parser.
1218 // We only support expressions created by the parser so far, not
1219 // expressions that have been resolved (many more classes would need
1220 // to implement CloneTo).
1222 // This infrastructure is here merely for Lambda expressions which
1223 // compile the same code using different type values for the same
1224 // arguments to find the correct overload
1226 public virtual Expression Clone (CloneContext clonectx)
1228 Expression cloned = (Expression) MemberwiseClone ();
1229 CloneTo (clonectx, cloned);
1235 // Implementation of expression to expression tree conversion
1237 public abstract Expression CreateExpressionTree (ResolveContext ec);
1239 protected Expression CreateExpressionFactoryCall (ResolveContext ec, string name, Arguments args)
1241 return CreateExpressionFactoryCall (ec, name, null, args, loc);
1244 protected Expression CreateExpressionFactoryCall (ResolveContext ec, string name, TypeArguments typeArguments, Arguments args)
1246 return CreateExpressionFactoryCall (ec, name, typeArguments, args, loc);
1249 public static Expression CreateExpressionFactoryCall (ResolveContext ec, string name, TypeArguments typeArguments, Arguments args, Location loc)
1251 return new Invocation (new MemberAccess (CreateExpressionTypeExpression (ec, loc), name, typeArguments, loc), args);
1254 protected static TypeExpr CreateExpressionTypeExpression (ResolveContext ec, Location loc)
1256 var t = ec.Module.PredefinedTypes.Expression.Resolve ();
1260 return new TypeExpression (t, loc);
1264 // Implemented by all expressions which support conversion from
1265 // compiler expression to invokable runtime expression. Used by
1266 // dynamic C# binder.
1268 public virtual SLE.Expression MakeExpression (BuilderContext ctx)
1270 throw new NotImplementedException ("MakeExpression for " + GetType ());
1273 public virtual object Accept (StructuralVisitor visitor)
1275 return visitor.Visit (this);
1280 /// This is just a base class for expressions that can
1281 /// appear on statements (invocations, object creation,
1282 /// assignments, post/pre increment and decrement). The idea
1283 /// being that they would support an extra Emition interface that
1284 /// does not leave a result on the stack.
1286 public abstract class ExpressionStatement : Expression
1288 public virtual void MarkReachable (Reachability rc)
1292 public virtual ExpressionStatement ResolveStatement (BlockContext ec)
1294 Expression e = Resolve (ec);
1298 ExpressionStatement es = e as ExpressionStatement;
1299 if (es == null || e is AnonymousMethodBody) {
1300 var reduced = e as IReducedExpressionStatement;
1301 if (reduced != null) {
1302 return EmptyExpressionStatement.Instance;
1305 Error_InvalidExpressionStatement (ec);
1309 // This is quite expensive warning, try to limit the damage
1311 if (MemberAccess.IsValidDotExpression (e.Type) && !(e is Assign || e is Await)) {
1312 WarningAsyncWithoutWait (ec, e);
1318 static void WarningAsyncWithoutWait (BlockContext bc, Expression e)
1320 if (bc.CurrentAnonymousMethod is AsyncInitializer) {
1321 var awaiter = new AwaitStatement.AwaitableMemberAccess (e) {
1326 // Need to do full resolve because GetAwaiter can be extension method
1327 // available only in this context
1329 var mg = awaiter.Resolve (bc) as MethodGroupExpr;
1333 var arguments = new Arguments (0);
1334 mg = mg.OverloadResolve (bc, ref arguments, null, OverloadResolver.Restrictions.ProbingOnly);
1339 // Use same check rules as for real await
1341 var awaiter_definition = bc.Module.GetAwaiter (mg.BestCandidateReturnType);
1342 if (!awaiter_definition.IsValidPattern || !awaiter_definition.INotifyCompletion)
1345 bc.Report.Warning (4014, 1, e.Location,
1346 "The statement is not awaited and execution of current method continues before the call is completed. Consider using `await' operator");
1350 var inv = e as Invocation;
1351 if (inv != null && inv.MethodGroup != null && inv.MethodGroup.BestCandidate.IsAsync) {
1352 // The warning won't be reported for imported methods to maintain warning compatiblity with csc
1353 bc.Report.Warning (4014, 1, e.Location,
1354 "The statement is not awaited and execution of current method continues before the call is completed. Consider using `await' operator or calling `Wait' method");
1360 /// Requests the expression to be emitted in a `statement'
1361 /// context. This means that no new value is left on the
1362 /// stack after invoking this method (constrasted with
1363 /// Emit that will always leave a value on the stack).
1365 public abstract void EmitStatement (EmitContext ec);
1367 public override void EmitSideEffect (EmitContext ec)
1373 interface IReducedExpressionStatement
1378 /// This kind of cast is used to encapsulate the child
1379 /// whose type is child.Type into an expression that is
1380 /// reported to return "return_type". This is used to encapsulate
1381 /// expressions which have compatible types, but need to be dealt
1382 /// at higher levels with.
1384 /// For example, a "byte" expression could be encapsulated in one
1385 /// of these as an "unsigned int". The type for the expression
1386 /// would be "unsigned int".
1389 public abstract class TypeCast : Expression
1391 protected readonly Expression child;
1393 protected TypeCast (Expression child, TypeSpec return_type)
1395 eclass = child.eclass;
1396 loc = child.Location;
1401 public Expression Child {
1407 public override bool ContainsEmitWithAwait ()
1409 return child.ContainsEmitWithAwait ();
1412 public override Expression CreateExpressionTree (ResolveContext ec)
1414 Arguments args = new Arguments (2);
1415 args.Add (new Argument (child.CreateExpressionTree (ec)));
1416 args.Add (new Argument (new TypeOf (type, loc)));
1418 if (type.IsPointer || child.Type.IsPointer)
1419 Error_PointerInsideExpressionTree (ec);
1421 return CreateExpressionFactoryCall (ec, ec.HasSet (ResolveContext.Options.CheckedScope) ? "ConvertChecked" : "Convert", args);
1424 protected override Expression DoResolve (ResolveContext ec)
1426 // This should never be invoked, we are born in fully
1427 // initialized state.
1432 public override void Emit (EmitContext ec)
1437 public override void FlowAnalysis (FlowAnalysisContext fc)
1439 child.FlowAnalysis (fc);
1442 public override SLE.Expression MakeExpression (BuilderContext ctx)
1445 return base.MakeExpression (ctx);
1447 return ctx.HasSet (BuilderContext.Options.CheckedScope) ?
1448 SLE.Expression.ConvertChecked (child.MakeExpression (ctx), type.GetMetaInfo ()) :
1449 SLE.Expression.Convert (child.MakeExpression (ctx), type.GetMetaInfo ());
1453 protected override void CloneTo (CloneContext clonectx, Expression t)
1458 public override bool IsNull {
1459 get { return child.IsNull; }
1463 public class EmptyCast : TypeCast {
1464 EmptyCast (Expression child, TypeSpec target_type)
1465 : base (child, target_type)
1469 public static Expression Create (Expression child, TypeSpec type)
1471 Constant c = child as Constant;
1473 var enum_constant = c as EnumConstant;
1474 if (enum_constant != null)
1475 c = enum_constant.Child;
1477 if (!(c is ReducedExpression.ReducedConstantExpression)) {
1481 var res = c.ConvertImplicitly (type);
1487 EmptyCast e = child as EmptyCast;
1489 return new EmptyCast (e.child, type);
1491 return new EmptyCast (child, type);
1494 public override void EmitBranchable (EmitContext ec, Label label, bool on_true)
1496 child.EmitBranchable (ec, label, on_true);
1499 public override void EmitSideEffect (EmitContext ec)
1501 child.EmitSideEffect (ec);
1506 // Used for predefined type user operator (no obsolete check, etc.)
1508 public class OperatorCast : TypeCast
1510 readonly MethodSpec conversion_operator;
1512 public OperatorCast (Expression expr, TypeSpec target_type)
1513 : this (expr, target_type, target_type, false)
1517 public OperatorCast (Expression expr, TypeSpec target_type, bool find_explicit)
1518 : this (expr, target_type, target_type, find_explicit)
1522 public OperatorCast (Expression expr, TypeSpec declaringType, TypeSpec returnType, bool isExplicit)
1523 : base (expr, returnType)
1525 var op = isExplicit ? Operator.OpType.Explicit : Operator.OpType.Implicit;
1526 var mi = MemberCache.GetUserOperator (declaringType, op, true);
1529 foreach (MethodSpec oper in mi) {
1530 if (oper.ReturnType != returnType)
1533 if (oper.Parameters.Types[0] == expr.Type) {
1534 conversion_operator = oper;
1540 throw new InternalErrorException ("Missing predefined user operator between `{0}' and `{1}'",
1541 returnType.GetSignatureForError (), expr.Type.GetSignatureForError ());
1544 public override void Emit (EmitContext ec)
1547 ec.Emit (OpCodes.Call, conversion_operator);
1552 // Constant specialization of EmptyCast.
1553 // We need to special case this since an empty cast of
1554 // a constant is still a constant.
1556 public class EmptyConstantCast : Constant
1558 public readonly Constant child;
1560 public EmptyConstantCast (Constant child, TypeSpec type)
1561 : base (child.Location)
1564 throw new ArgumentNullException ("child");
1567 this.eclass = child.eclass;
1571 public override Constant ConvertExplicitly (bool in_checked_context, TypeSpec target_type)
1573 if (child.Type == target_type)
1576 // FIXME: check that 'type' can be converted to 'target_type' first
1577 return child.ConvertExplicitly (in_checked_context, target_type);
1580 public override Expression CreateExpressionTree (ResolveContext ec)
1582 Arguments args = Arguments.CreateForExpressionTree (ec, null,
1583 child.CreateExpressionTree (ec),
1584 new TypeOf (type, loc));
1587 Error_PointerInsideExpressionTree (ec);
1589 return CreateExpressionFactoryCall (ec, "Convert", args);
1592 public override bool IsDefaultValue {
1593 get { return child.IsDefaultValue; }
1596 public override bool IsNegative {
1597 get { return child.IsNegative; }
1600 public override bool IsNull {
1601 get { return child.IsNull; }
1604 public override bool IsOneInteger {
1605 get { return child.IsOneInteger; }
1608 public override bool IsSideEffectFree {
1610 return child.IsSideEffectFree;
1614 public override bool IsZeroInteger {
1615 get { return child.IsZeroInteger; }
1618 public override void Emit (EmitContext ec)
1623 public override void EmitBranchable (EmitContext ec, Label label, bool on_true)
1625 child.EmitBranchable (ec, label, on_true);
1627 // Only to make verifier happy
1628 if (TypeManager.IsGenericParameter (type) && child.IsNull)
1629 ec.Emit (OpCodes.Unbox_Any, type);
1632 public override void EmitSideEffect (EmitContext ec)
1634 child.EmitSideEffect (ec);
1637 public override object GetValue ()
1639 return child.GetValue ();
1642 public override string GetValueAsLiteral ()
1644 return child.GetValueAsLiteral ();
1647 public override long GetValueAsLong ()
1649 return child.GetValueAsLong ();
1652 public override Constant ConvertImplicitly (TypeSpec target_type)
1654 if (type == target_type)
1657 // FIXME: Do we need to check user conversions?
1658 if (!Convert.ImplicitStandardConversionExists (this, target_type))
1661 return child.ConvertImplicitly (target_type);
1666 /// This class is used to wrap literals which belong inside Enums
1668 public class EnumConstant : Constant
1670 public Constant Child;
1672 public EnumConstant (Constant child, TypeSpec enum_type)
1673 : base (child.Location)
1677 this.eclass = ExprClass.Value;
1678 this.type = enum_type;
1681 protected EnumConstant (Location loc)
1686 public override void Emit (EmitContext ec)
1691 public override void EncodeAttributeValue (IMemberContext rc, AttributeEncoder enc, TypeSpec targetType, TypeSpec parameterType)
1693 Child.EncodeAttributeValue (rc, enc, Child.Type, parameterType);
1696 public override void EmitBranchable (EmitContext ec, Label label, bool on_true)
1698 Child.EmitBranchable (ec, label, on_true);
1701 public override void EmitSideEffect (EmitContext ec)
1703 Child.EmitSideEffect (ec);
1706 public override string GetSignatureForError()
1708 return Type.GetSignatureForError ();
1711 public override object GetValue ()
1713 return Child.GetValue ();
1717 public override object GetTypedValue ()
1720 // The method can be used in dynamic context only (on closed types)
1722 // System.Enum.ToObject cannot be called on dynamic types
1723 // EnumBuilder has to be used, but we cannot use EnumBuilder
1724 // because it does not properly support generics
1726 return System.Enum.ToObject (type.GetMetaInfo (), Child.GetValue ());
1730 public override string GetValueAsLiteral ()
1732 return Child.GetValueAsLiteral ();
1735 public override long GetValueAsLong ()
1737 return Child.GetValueAsLong ();
1740 public EnumConstant Increment()
1742 return new EnumConstant (((IntegralConstant) Child).Increment (), type);
1745 public override bool IsDefaultValue {
1747 return Child.IsDefaultValue;
1751 public override bool IsSideEffectFree {
1753 return Child.IsSideEffectFree;
1757 public override bool IsZeroInteger {
1758 get { return Child.IsZeroInteger; }
1761 public override bool IsNegative {
1763 return Child.IsNegative;
1767 public override Constant ConvertExplicitly (bool in_checked_context, TypeSpec target_type)
1769 if (Child.Type == target_type)
1772 return Child.ConvertExplicitly (in_checked_context, target_type);
1775 public override Constant ConvertImplicitly (TypeSpec type)
1777 if (this.type == type) {
1781 if (!Convert.ImplicitStandardConversionExists (this, type)){
1785 return Child.ConvertImplicitly (type);
1790 /// This kind of cast is used to encapsulate Value Types in objects.
1792 /// The effect of it is to box the value type emitted by the previous
1795 public class BoxedCast : TypeCast {
1797 public BoxedCast (Expression expr, TypeSpec target_type)
1798 : base (expr, target_type)
1800 eclass = ExprClass.Value;
1803 protected override Expression DoResolve (ResolveContext ec)
1805 // This should never be invoked, we are born in fully
1806 // initialized state.
1811 public override void EncodeAttributeValue (IMemberContext rc, AttributeEncoder enc, TypeSpec targetType, TypeSpec parameterType)
1813 // Only boxing to object type is supported
1814 if (targetType.BuiltinType != BuiltinTypeSpec.Type.Object) {
1815 base.EncodeAttributeValue (rc, enc, targetType, parameterType);
1819 enc.Encode (child.Type);
1820 child.EncodeAttributeValue (rc, enc, child.Type, parameterType);
1823 public override void Emit (EmitContext ec)
1827 ec.Emit (OpCodes.Box, child.Type);
1830 public override void EmitSideEffect (EmitContext ec)
1832 // boxing is side-effectful, since it involves runtime checks, except when boxing to Object or ValueType
1833 // so, we need to emit the box+pop instructions in most cases
1834 if (child.Type.IsStruct &&
1835 (type.BuiltinType == BuiltinTypeSpec.Type.Object || type.BuiltinType == BuiltinTypeSpec.Type.ValueType))
1836 child.EmitSideEffect (ec);
1838 base.EmitSideEffect (ec);
1842 public class UnboxCast : TypeCast {
1843 public UnboxCast (Expression expr, TypeSpec return_type)
1844 : base (expr, return_type)
1848 protected override Expression DoResolve (ResolveContext ec)
1850 // This should never be invoked, we are born in fully
1851 // initialized state.
1856 public override void Emit (EmitContext ec)
1860 ec.Emit (OpCodes.Unbox_Any, type);
1865 /// This is used to perform explicit numeric conversions.
1867 /// Explicit numeric conversions might trigger exceptions in a checked
1868 /// context, so they should generate the conv.ovf opcodes instead of
1871 public class ConvCast : TypeCast {
1872 public enum Mode : byte {
1873 I1_U1, I1_U2, I1_U4, I1_U8, I1_CH,
1875 I2_I1, I2_U1, I2_U2, I2_U4, I2_U8, I2_CH,
1876 U2_I1, U2_U1, U2_I2, U2_CH,
1877 I4_I1, I4_U1, I4_I2, I4_U2, I4_U4, I4_U8, I4_CH,
1878 U4_I1, U4_U1, U4_I2, U4_U2, U4_I4, U4_CH,
1879 I8_I1, I8_U1, I8_I2, I8_U2, I8_I4, I8_U4, I8_U8, I8_CH, I8_I,
1880 U8_I1, U8_U1, U8_I2, U8_U2, U8_I4, U8_U4, U8_I8, U8_CH, U8_I,
1881 CH_I1, CH_U1, CH_I2,
1882 R4_I1, R4_U1, R4_I2, R4_U2, R4_I4, R4_U4, R4_I8, R4_U8, R4_CH,
1883 R8_I1, R8_U1, R8_I2, R8_U2, R8_I4, R8_U4, R8_I8, R8_U8, R8_CH, R8_R4,
1889 public ConvCast (Expression child, TypeSpec return_type, Mode m)
1890 : base (child, return_type)
1895 protected override Expression DoResolve (ResolveContext ec)
1897 // This should never be invoked, we are born in fully
1898 // initialized state.
1903 public override string ToString ()
1905 return String.Format ("ConvCast ({0}, {1})", mode, child);
1908 public override void Emit (EmitContext ec)
1914 public static void Emit (EmitContext ec, Mode mode)
1916 if (ec.HasSet (EmitContext.Options.CheckedScope)) {
1918 case Mode.I1_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
1919 case Mode.I1_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1920 case Mode.I1_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
1921 case Mode.I1_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
1922 case Mode.I1_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1924 case Mode.U1_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
1925 case Mode.U1_CH: /* nothing */ break;
1927 case Mode.I2_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
1928 case Mode.I2_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
1929 case Mode.I2_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1930 case Mode.I2_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
1931 case Mode.I2_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
1932 case Mode.I2_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1934 case Mode.U2_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
1935 case Mode.U2_U1: ec.Emit (OpCodes.Conv_Ovf_U1_Un); break;
1936 case Mode.U2_I2: ec.Emit (OpCodes.Conv_Ovf_I2_Un); break;
1937 case Mode.U2_CH: /* nothing */ break;
1939 case Mode.I4_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
1940 case Mode.I4_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
1941 case Mode.I4_I2: ec.Emit (OpCodes.Conv_Ovf_I2); break;
1942 case Mode.I4_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
1943 case Mode.I4_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1944 case Mode.I4_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
1945 case Mode.I4_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1947 case Mode.U4_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
1948 case Mode.U4_U1: ec.Emit (OpCodes.Conv_Ovf_U1_Un); break;
1949 case Mode.U4_I2: ec.Emit (OpCodes.Conv_Ovf_I2_Un); break;
1950 case Mode.U4_U2: ec.Emit (OpCodes.Conv_Ovf_U2_Un); break;
1951 case Mode.U4_I4: ec.Emit (OpCodes.Conv_Ovf_I4_Un); break;
1952 case Mode.U4_CH: ec.Emit (OpCodes.Conv_Ovf_U2_Un); break;
1954 case Mode.I8_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
1955 case Mode.I8_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
1956 case Mode.I8_I2: ec.Emit (OpCodes.Conv_Ovf_I2); break;
1957 case Mode.I8_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1958 case Mode.I8_I4: ec.Emit (OpCodes.Conv_Ovf_I4); break;
1959 case Mode.I8_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
1960 case Mode.I8_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
1961 case Mode.I8_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1962 case Mode.I8_I: ec.Emit (OpCodes.Conv_Ovf_U); break;
1964 case Mode.U8_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
1965 case Mode.U8_U1: ec.Emit (OpCodes.Conv_Ovf_U1_Un); break;
1966 case Mode.U8_I2: ec.Emit (OpCodes.Conv_Ovf_I2_Un); break;
1967 case Mode.U8_U2: ec.Emit (OpCodes.Conv_Ovf_U2_Un); break;
1968 case Mode.U8_I4: ec.Emit (OpCodes.Conv_Ovf_I4_Un); break;
1969 case Mode.U8_U4: ec.Emit (OpCodes.Conv_Ovf_U4_Un); break;
1970 case Mode.U8_I8: ec.Emit (OpCodes.Conv_Ovf_I8_Un); break;
1971 case Mode.U8_CH: ec.Emit (OpCodes.Conv_Ovf_U2_Un); break;
1972 case Mode.U8_I: ec.Emit (OpCodes.Conv_Ovf_U_Un); break;
1974 case Mode.CH_I1: ec.Emit (OpCodes.Conv_Ovf_I1_Un); break;
1975 case Mode.CH_U1: ec.Emit (OpCodes.Conv_Ovf_U1_Un); break;
1976 case Mode.CH_I2: ec.Emit (OpCodes.Conv_Ovf_I2_Un); break;
1978 case Mode.R4_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
1979 case Mode.R4_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
1980 case Mode.R4_I2: ec.Emit (OpCodes.Conv_Ovf_I2); break;
1981 case Mode.R4_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1982 case Mode.R4_I4: ec.Emit (OpCodes.Conv_Ovf_I4); break;
1983 case Mode.R4_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
1984 case Mode.R4_I8: ec.Emit (OpCodes.Conv_Ovf_I8); break;
1985 case Mode.R4_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
1986 case Mode.R4_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1988 case Mode.R8_I1: ec.Emit (OpCodes.Conv_Ovf_I1); break;
1989 case Mode.R8_U1: ec.Emit (OpCodes.Conv_Ovf_U1); break;
1990 case Mode.R8_I2: ec.Emit (OpCodes.Conv_Ovf_I2); break;
1991 case Mode.R8_U2: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1992 case Mode.R8_I4: ec.Emit (OpCodes.Conv_Ovf_I4); break;
1993 case Mode.R8_U4: ec.Emit (OpCodes.Conv_Ovf_U4); break;
1994 case Mode.R8_I8: ec.Emit (OpCodes.Conv_Ovf_I8); break;
1995 case Mode.R8_U8: ec.Emit (OpCodes.Conv_Ovf_U8); break;
1996 case Mode.R8_CH: ec.Emit (OpCodes.Conv_Ovf_U2); break;
1997 case Mode.R8_R4: ec.Emit (OpCodes.Conv_R4); break;
1999 case Mode.I_I8: ec.Emit (OpCodes.Conv_Ovf_I8_Un); break;
2003 case Mode.I1_U1: ec.Emit (OpCodes.Conv_U1); break;
2004 case Mode.I1_U2: ec.Emit (OpCodes.Conv_U2); break;
2005 case Mode.I1_U4: ec.Emit (OpCodes.Conv_U4); break;
2006 case Mode.I1_U8: ec.Emit (OpCodes.Conv_I8); break;
2007 case Mode.I1_CH: ec.Emit (OpCodes.Conv_U2); break;
2009 case Mode.U1_I1: ec.Emit (OpCodes.Conv_I1); break;
2010 case Mode.U1_CH: ec.Emit (OpCodes.Conv_U2); break;
2012 case Mode.I2_I1: ec.Emit (OpCodes.Conv_I1); break;
2013 case Mode.I2_U1: ec.Emit (OpCodes.Conv_U1); break;
2014 case Mode.I2_U2: ec.Emit (OpCodes.Conv_U2); break;
2015 case Mode.I2_U4: ec.Emit (OpCodes.Conv_U4); break;
2016 case Mode.I2_U8: ec.Emit (OpCodes.Conv_I8); break;
2017 case Mode.I2_CH: ec.Emit (OpCodes.Conv_U2); break;
2019 case Mode.U2_I1: ec.Emit (OpCodes.Conv_I1); break;
2020 case Mode.U2_U1: ec.Emit (OpCodes.Conv_U1); break;
2021 case Mode.U2_I2: ec.Emit (OpCodes.Conv_I2); break;
2022 case Mode.U2_CH: /* nothing */ break;
2024 case Mode.I4_I1: ec.Emit (OpCodes.Conv_I1); break;
2025 case Mode.I4_U1: ec.Emit (OpCodes.Conv_U1); break;
2026 case Mode.I4_I2: ec.Emit (OpCodes.Conv_I2); break;
2027 case Mode.I4_U4: /* nothing */ break;
2028 case Mode.I4_U2: ec.Emit (OpCodes.Conv_U2); break;
2029 case Mode.I4_U8: ec.Emit (OpCodes.Conv_I8); break;
2030 case Mode.I4_CH: ec.Emit (OpCodes.Conv_U2); break;
2032 case Mode.U4_I1: ec.Emit (OpCodes.Conv_I1); break;
2033 case Mode.U4_U1: ec.Emit (OpCodes.Conv_U1); break;
2034 case Mode.U4_I2: ec.Emit (OpCodes.Conv_I2); break;
2035 case Mode.U4_U2: ec.Emit (OpCodes.Conv_U2); break;
2036 case Mode.U4_I4: /* nothing */ break;
2037 case Mode.U4_CH: ec.Emit (OpCodes.Conv_U2); break;
2039 case Mode.I8_I1: ec.Emit (OpCodes.Conv_I1); break;
2040 case Mode.I8_U1: ec.Emit (OpCodes.Conv_U1); break;
2041 case Mode.I8_I2: ec.Emit (OpCodes.Conv_I2); break;
2042 case Mode.I8_U2: ec.Emit (OpCodes.Conv_U2); break;
2043 case Mode.I8_I4: ec.Emit (OpCodes.Conv_I4); break;
2044 case Mode.I8_U4: ec.Emit (OpCodes.Conv_U4); break;
2045 case Mode.I8_U8: /* nothing */ break;
2046 case Mode.I8_CH: ec.Emit (OpCodes.Conv_U2); break;
2047 case Mode.I8_I: ec.Emit (OpCodes.Conv_U); break;
2049 case Mode.U8_I1: ec.Emit (OpCodes.Conv_I1); break;
2050 case Mode.U8_U1: ec.Emit (OpCodes.Conv_U1); break;
2051 case Mode.U8_I2: ec.Emit (OpCodes.Conv_I2); break;
2052 case Mode.U8_U2: ec.Emit (OpCodes.Conv_U2); break;
2053 case Mode.U8_I4: ec.Emit (OpCodes.Conv_I4); break;
2054 case Mode.U8_U4: ec.Emit (OpCodes.Conv_U4); break;
2055 case Mode.U8_I8: /* nothing */ break;
2056 case Mode.U8_CH: ec.Emit (OpCodes.Conv_U2); break;
2057 case Mode.U8_I: ec.Emit (OpCodes.Conv_U); break;
2059 case Mode.CH_I1: ec.Emit (OpCodes.Conv_I1); break;
2060 case Mode.CH_U1: ec.Emit (OpCodes.Conv_U1); break;
2061 case Mode.CH_I2: ec.Emit (OpCodes.Conv_I2); break;
2063 case Mode.R4_I1: ec.Emit (OpCodes.Conv_I1); break;
2064 case Mode.R4_U1: ec.Emit (OpCodes.Conv_U1); break;
2065 case Mode.R4_I2: ec.Emit (OpCodes.Conv_I2); break;
2066 case Mode.R4_U2: ec.Emit (OpCodes.Conv_U2); break;
2067 case Mode.R4_I4: ec.Emit (OpCodes.Conv_I4); break;
2068 case Mode.R4_U4: ec.Emit (OpCodes.Conv_U4); break;
2069 case Mode.R4_I8: ec.Emit (OpCodes.Conv_I8); break;
2070 case Mode.R4_U8: ec.Emit (OpCodes.Conv_U8); break;
2071 case Mode.R4_CH: ec.Emit (OpCodes.Conv_U2); break;
2073 case Mode.R8_I1: ec.Emit (OpCodes.Conv_I1); break;
2074 case Mode.R8_U1: ec.Emit (OpCodes.Conv_U1); break;
2075 case Mode.R8_I2: ec.Emit (OpCodes.Conv_I2); break;
2076 case Mode.R8_U2: ec.Emit (OpCodes.Conv_U2); break;
2077 case Mode.R8_I4: ec.Emit (OpCodes.Conv_I4); break;
2078 case Mode.R8_U4: ec.Emit (OpCodes.Conv_U4); break;
2079 case Mode.R8_I8: ec.Emit (OpCodes.Conv_I8); break;
2080 case Mode.R8_U8: ec.Emit (OpCodes.Conv_U8); break;
2081 case Mode.R8_CH: ec.Emit (OpCodes.Conv_U2); break;
2082 case Mode.R8_R4: ec.Emit (OpCodes.Conv_R4); break;
2084 case Mode.I_I8: ec.Emit (OpCodes.Conv_U8); break;
2090 class OpcodeCast : TypeCast
2094 public OpcodeCast (Expression child, TypeSpec return_type, OpCode op)
2095 : base (child, return_type)
2100 protected override Expression DoResolve (ResolveContext ec)
2102 // This should never be invoked, we are born in fully
2103 // initialized state.
2108 public override void Emit (EmitContext ec)
2114 public TypeSpec UnderlyingType {
2115 get { return child.Type; }
2120 // Opcode casts expression with 2 opcodes but only
2121 // single expression tree node
2123 class OpcodeCastDuplex : OpcodeCast
2125 readonly OpCode second;
2127 public OpcodeCastDuplex (Expression child, TypeSpec returnType, OpCode first, OpCode second)
2128 : base (child, returnType, first)
2130 this.second = second;
2133 public override void Emit (EmitContext ec)
2141 /// This kind of cast is used to encapsulate a child and cast it
2142 /// to the class requested
2144 public sealed class ClassCast : TypeCast {
2145 readonly bool forced;
2147 public ClassCast (Expression child, TypeSpec return_type)
2148 : base (child, return_type)
2152 public ClassCast (Expression child, TypeSpec return_type, bool forced)
2153 : base (child, return_type)
2155 this.forced = forced;
2158 public override void Emit (EmitContext ec)
2162 bool gen = TypeManager.IsGenericParameter (child.Type);
2164 ec.Emit (OpCodes.Box, child.Type);
2166 if (type.IsGenericParameter) {
2167 ec.Emit (OpCodes.Unbox_Any, type);
2174 ec.Emit (OpCodes.Castclass, type);
2179 // Created during resolving pahse when an expression is wrapped or constantified
2180 // and original expression can be used later (e.g. for expression trees)
2182 public class ReducedExpression : Expression
2184 public class ReducedConstantExpression : EmptyConstantCast
2186 readonly Expression orig_expr;
2188 public ReducedConstantExpression (Constant expr, Expression orig_expr)
2189 : base (expr, expr.Type)
2191 this.orig_expr = orig_expr;
2194 public Expression OriginalExpression {
2200 public override Constant ConvertImplicitly (TypeSpec target_type)
2202 Constant c = base.ConvertImplicitly (target_type);
2204 c = new ReducedConstantExpression (c, orig_expr);
2209 public override Expression CreateExpressionTree (ResolveContext ec)
2211 return orig_expr.CreateExpressionTree (ec);
2214 public override Constant ConvertExplicitly (bool in_checked_context, TypeSpec target_type)
2216 Constant c = base.ConvertExplicitly (in_checked_context, target_type);
2218 c = new ReducedConstantExpression (c, orig_expr);
2222 public override void EncodeAttributeValue (IMemberContext rc, AttributeEncoder enc, TypeSpec targetType, TypeSpec parameterType)
2225 // LAMESPEC: Reduced conditional expression is allowed as an attribute argument
2227 if (orig_expr is Conditional)
2228 child.EncodeAttributeValue (rc, enc, targetType,parameterType);
2230 base.EncodeAttributeValue (rc, enc, targetType, parameterType);
2234 sealed class ReducedConstantStatement : ReducedConstantExpression, IReducedExpressionStatement
2236 public ReducedConstantStatement (Constant expr, Expression origExpr)
2237 : base (expr, origExpr)
2242 sealed class ReducedExpressionStatement : ExpressionStatement
2244 readonly Expression orig_expr;
2245 readonly ExpressionStatement stm;
2247 public ReducedExpressionStatement (ExpressionStatement stm, Expression orig)
2249 this.orig_expr = orig;
2251 this.eclass = stm.eclass;
2252 this.type = stm.Type;
2254 this.loc = orig.Location;
2257 public override bool ContainsEmitWithAwait ()
2259 return stm.ContainsEmitWithAwait ();
2262 public override Expression CreateExpressionTree (ResolveContext ec)
2264 return orig_expr.CreateExpressionTree (ec);
2267 protected override Expression DoResolve (ResolveContext ec)
2272 public override void Emit (EmitContext ec)
2277 public override void EmitStatement (EmitContext ec)
2279 stm.EmitStatement (ec);
2282 public override void FlowAnalysis (FlowAnalysisContext fc)
2284 stm.FlowAnalysis (fc);
2288 readonly Expression expr, orig_expr;
2290 private ReducedExpression (Expression expr, Expression orig_expr)
2293 this.eclass = expr.eclass;
2294 this.type = expr.Type;
2295 this.orig_expr = orig_expr;
2296 this.loc = orig_expr.Location;
2301 public override bool IsSideEffectFree {
2303 return expr.IsSideEffectFree;
2307 public Expression OriginalExpression {
2315 public override bool ContainsEmitWithAwait ()
2317 return expr.ContainsEmitWithAwait ();
2321 // Creates fully resolved expression switcher
2323 public static Constant Create (Constant expr, Expression originalExpr)
2325 if (expr.eclass == ExprClass.Unresolved)
2326 throw new ArgumentException ("Unresolved expression");
2328 if (originalExpr is ExpressionStatement)
2329 return new ReducedConstantStatement (expr, originalExpr);
2331 return new ReducedConstantExpression (expr, originalExpr);
2334 public static ExpressionStatement Create (ExpressionStatement s, Expression orig)
2336 return new ReducedExpressionStatement (s, orig);
2339 public static Expression Create (Expression expr, Expression original_expr)
2341 return Create (expr, original_expr, true);
2345 // Creates unresolved reduce expression. The original expression has to be
2346 // already resolved. Created expression is constant based based on `expr'
2347 // value unless canBeConstant is used
2349 public static Expression Create (Expression expr, Expression original_expr, bool canBeConstant)
2351 if (canBeConstant) {
2352 Constant c = expr as Constant;
2354 return Create (c, original_expr);
2357 ExpressionStatement s = expr as ExpressionStatement;
2359 return Create (s, original_expr);
2361 if (expr.eclass == ExprClass.Unresolved)
2362 throw new ArgumentException ("Unresolved expression");
2364 return new ReducedExpression (expr, original_expr);
2367 public override Expression CreateExpressionTree (ResolveContext ec)
2369 return orig_expr.CreateExpressionTree (ec);
2372 protected override Expression DoResolve (ResolveContext ec)
2377 public override void Emit (EmitContext ec)
2382 public override Expression EmitToField (EmitContext ec)
2384 return expr.EmitToField(ec);
2387 public override void EmitBranchable (EmitContext ec, Label target, bool on_true)
2389 expr.EmitBranchable (ec, target, on_true);
2392 public override void FlowAnalysis (FlowAnalysisContext fc)
2394 expr.FlowAnalysis (fc);
2397 public override SLE.Expression MakeExpression (BuilderContext ctx)
2399 return orig_expr.MakeExpression (ctx);
2404 // Standard composite pattern
2406 public abstract class CompositeExpression : Expression
2408 protected Expression expr;
2410 protected CompositeExpression (Expression expr)
2413 this.loc = expr.Location;
2416 public override bool ContainsEmitWithAwait ()
2418 return expr.ContainsEmitWithAwait ();
2421 public override Expression CreateExpressionTree (ResolveContext rc)
2423 return expr.CreateExpressionTree (rc);
2426 public Expression Child {
2427 get { return expr; }
2430 protected override Expression DoResolve (ResolveContext rc)
2432 expr = expr.Resolve (rc);
2437 eclass = expr.eclass;
2441 public override void Emit (EmitContext ec)
2446 public override bool IsNull {
2447 get { return expr.IsNull; }
2452 // Base of expressions used only to narrow resolve flow
2454 public abstract class ShimExpression : Expression
2456 protected Expression expr;
2458 protected ShimExpression (Expression expr)
2463 public Expression Expr {
2469 protected override void CloneTo (CloneContext clonectx, Expression t)
2474 ShimExpression target = (ShimExpression) t;
2475 target.expr = expr.Clone (clonectx);
2478 public override bool ContainsEmitWithAwait ()
2480 return expr.ContainsEmitWithAwait ();
2483 public override Expression CreateExpressionTree (ResolveContext ec)
2485 throw new NotSupportedException ("ET");
2488 public override void Emit (EmitContext ec)
2490 throw new InternalErrorException ("Missing Resolve call");
2494 public class UnreachableExpression : Expression
2496 public UnreachableExpression (Expression expr)
2498 this.loc = expr.Location;
2501 public override Expression CreateExpressionTree (ResolveContext ec)
2504 throw new NotImplementedException ();
2507 protected override Expression DoResolve (ResolveContext rc)
2509 throw new NotSupportedException ();
2512 public override void FlowAnalysis (FlowAnalysisContext fc)
2514 fc.Report.Warning (429, 4, loc, "Unreachable expression code detected");
2517 public override void Emit (EmitContext ec)
2521 public override void EmitBranchable (EmitContext ec, Label target, bool on_true)
2527 // Unresolved type name expressions
2529 public abstract class ATypeNameExpression : FullNamedExpression
2532 protected TypeArguments targs;
2534 protected ATypeNameExpression (string name, Location l)
2540 protected ATypeNameExpression (string name, TypeArguments targs, Location l)
2547 protected ATypeNameExpression (string name, int arity, Location l)
2548 : this (name, new UnboundTypeArguments (arity, l), l)
2556 return targs == null ? 0 : targs.Count;
2560 public bool HasTypeArguments {
2562 return targs != null && !targs.IsEmpty;
2566 public string Name {
2575 public TypeArguments TypeArguments {
2583 public override bool Equals (object obj)
2585 ATypeNameExpression atne = obj as ATypeNameExpression;
2586 return atne != null && atne.Name == Name &&
2587 (targs == null || targs.Equals (atne.targs));
2590 public override int GetHashCode ()
2592 return Name.GetHashCode ();
2595 // TODO: Move it to MemberCore
2596 public static string GetMemberType (MemberCore mc)
2602 if (mc is FieldBase)
2604 if (mc is MethodCore)
2606 if (mc is EnumMember)
2614 public override string GetSignatureForError ()
2616 if (targs != null) {
2617 return Name + "<" + targs.GetSignatureForError () + ">";
2623 public abstract Expression LookupNameExpression (ResolveContext rc, MemberLookupRestrictions restriction);
2627 /// SimpleName expressions are formed of a single word and only happen at the beginning
2628 /// of a dotted-name.
2630 public class SimpleName : ATypeNameExpression
2632 public SimpleName (string name, Location l)
2637 public SimpleName (string name, TypeArguments args, Location l)
2638 : base (name, args, l)
2642 public SimpleName (string name, int arity, Location l)
2643 : base (name, arity, l)
2647 public SimpleName GetMethodGroup ()
2649 return new SimpleName (Name, targs, loc);
2652 protected override Expression DoResolve (ResolveContext rc)
2654 return SimpleNameResolve (rc, null);
2657 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
2659 return SimpleNameResolve (ec, right_side);
2662 public void Error_NameDoesNotExist (ResolveContext rc)
2664 rc.Report.Error (103, loc, "The name `{0}' does not exist in the current context", Name);
2667 protected virtual void Error_TypeOrNamespaceNotFound (IMemberContext ctx)
2669 if (ctx.CurrentType != null) {
2670 var member = MemberLookup (ctx, false, ctx.CurrentType, Name, 0, MemberLookupRestrictions.ExactArity, loc) as MemberExpr;
2671 if (member != null) {
2672 Error_UnexpectedKind (ctx, member, "type", member.KindName, loc);
2677 var report = ctx.Module.Compiler.Report;
2679 var retval = ctx.LookupNamespaceOrType (Name, Arity, LookupMode.IgnoreAccessibility, loc);
2680 if (retval != null) {
2681 report.SymbolRelatedToPreviousError (retval.Type);
2682 ErrorIsInaccesible (ctx, retval.GetSignatureForError (), loc);
2686 retval = ctx.LookupNamespaceOrType (Name, -System.Math.Max (1, Arity), LookupMode.Probing, loc);
2687 if (retval != null) {
2688 Error_TypeArgumentsCannotBeUsed (ctx, retval.Type, loc);
2692 var ns_candidates = ctx.Module.GlobalRootNamespace.FindTypeNamespaces (ctx, Name, Arity);
2693 if (ns_candidates != null) {
2694 if (ctx is UsingAliasNamespace.AliasContext) {
2695 report.Error (246, loc,
2696 "The type or namespace name `{1}' could not be found. Consider using fully qualified name `{0}.{1}'",
2697 ns_candidates[0], Name);
2699 string usings = string.Join ("' or `", ns_candidates.ToArray ());
2700 report.Error (246, loc,
2701 "The type or namespace name `{0}' could not be found. Are you missing `{1}' using directive?",
2705 report.Error (246, loc,
2706 "The type or namespace name `{0}' could not be found. Are you missing an assembly reference?",
2711 public override FullNamedExpression ResolveAsTypeOrNamespace (IMemberContext mc, bool allowUnboundTypeArguments)
2713 FullNamedExpression fne = mc.LookupNamespaceOrType (Name, Arity, LookupMode.Normal, loc);
2716 if (fne.Type != null && Arity > 0) {
2717 if (HasTypeArguments) {
2718 GenericTypeExpr ct = new GenericTypeExpr (fne.Type, targs, loc);
2719 if (ct.ResolveAsType (mc) == null)
2725 targs.Resolve (mc, allowUnboundTypeArguments);
2727 return new GenericOpenTypeExpr (fne.Type, loc);
2731 // dynamic namespace is ignored when dynamic is allowed (does not apply to types)
2733 if (!(fne is NamespaceExpression))
2737 if (Arity == 0 && Name == "dynamic" && !(mc is NamespaceContainer) && mc.Module.Compiler.Settings.Version > LanguageVersion.V_3) {
2738 if (!mc.Module.PredefinedAttributes.Dynamic.IsDefined) {
2739 mc.Module.Compiler.Report.Error (1980, Location,
2740 "Dynamic keyword requires `{0}' to be defined. Are you missing System.Core.dll assembly reference?",
2741 mc.Module.PredefinedAttributes.Dynamic.GetSignatureForError ());
2744 fne = new DynamicTypeExpr (loc);
2745 fne.ResolveAsType (mc);
2751 Error_TypeOrNamespaceNotFound (mc);
2755 public bool IsPossibleTypeOrNamespace (IMemberContext mc)
2757 return mc.LookupNamespaceOrType (Name, Arity, LookupMode.Probing, loc) != null;
2760 public bool IsPossibleType (IMemberContext mc)
2762 return mc.LookupNamespaceOrType (Name, Arity, LookupMode.Probing, loc) is TypeExpr;
2765 public override Expression LookupNameExpression (ResolveContext rc, MemberLookupRestrictions restrictions)
2767 int lookup_arity = Arity;
2768 bool errorMode = false;
2770 Block current_block = rc.CurrentBlock;
2771 INamedBlockVariable variable = null;
2772 bool variable_found = false;
2776 // Stage 1: binding to local variables or parameters
2778 // LAMESPEC: It should take invocableOnly into account but that would break csc compatibility
2780 if (current_block != null && lookup_arity == 0) {
2781 if (current_block.ParametersBlock.TopBlock.GetLocalName (Name, current_block.Original, ref variable)) {
2782 if (!variable.IsDeclared) {
2783 // We found local name in accessible block but it's not
2784 // initialized yet, maybe the user wanted to bind to something else
2786 variable_found = true;
2788 e = variable.CreateReferenceExpression (rc, loc);
2791 Error_TypeArgumentsCannotBeUsed (rc, "variable", Name, loc);
2800 // Stage 2: Lookup members if we are inside a type up to top level type for nested types
2802 TypeSpec member_type = rc.CurrentType;
2803 for (; member_type != null; member_type = member_type.DeclaringType) {
2804 e = MemberLookup (rc, errorMode, member_type, Name, lookup_arity, restrictions, loc);
2808 var me = e as MemberExpr;
2810 // The name matches a type, defer to ResolveAsTypeStep
2818 if (variable != null) {
2819 if (me is FieldExpr || me is ConstantExpr || me is EventExpr || me is PropertyExpr) {
2820 rc.Report.Error (844, loc,
2821 "A local variable `{0}' cannot be used before it is declared. Consider renaming the local variable when it hides the member `{1}'",
2822 Name, me.GetSignatureForError ());
2826 } else if (me is MethodGroupExpr || me is PropertyExpr || me is IndexerExpr) {
2827 // Leave it to overload resolution to report correct error
2829 // TODO: rc.Report.SymbolRelatedToPreviousError ()
2830 ErrorIsInaccesible (rc, me.GetSignatureForError (), loc);
2834 // MemberLookup does not check accessors availability, this is actually needed for properties only
2836 var pe = me as PropertyExpr;
2839 // Break as there is no other overload available anyway
2840 if ((restrictions & MemberLookupRestrictions.ReadAccess) != 0) {
2841 if (!pe.PropertyInfo.HasGet || !pe.PropertyInfo.Get.IsAccessible (rc))
2844 pe.Getter = pe.PropertyInfo.Get;
2846 if (!pe.PropertyInfo.HasSet) {
2847 if (rc.HasSet (ResolveContext.Options.ConstructorScope) && pe.IsAutoPropertyAccess &&
2848 pe.PropertyInfo.DeclaringType == rc.CurrentType && pe.IsStatic == rc.IsStatic) {
2849 var p = (Property) pe.PropertyInfo.MemberDefinition;
2850 return new FieldExpr (p.BackingField, loc);
2853 variable_found = true;
2857 if (!pe.PropertyInfo.Set.IsAccessible (rc)) {
2858 variable_found = true;
2862 pe.Setter = pe.PropertyInfo.Set;
2867 // TODO: It's used by EventExpr -> FieldExpr transformation only
2868 // TODO: Should go to MemberAccess
2869 me = me.ResolveMemberAccess (rc, null, null);
2872 targs.Resolve (rc, false);
2873 me.SetTypeArguments (rc, targs);
2879 var expr = NamespaceContainer.LookupStaticUsings (rc, Name, Arity, loc);
2882 targs.Resolve (rc, false);
2884 var me = expr as MemberExpr;
2886 me.SetTypeArguments (rc, targs);
2892 // Stage 3: Lookup nested types, namespaces and type parameters in the context
2894 if ((restrictions & MemberLookupRestrictions.InvocableOnly) == 0 && !variable_found) {
2895 if (IsPossibleTypeOrNamespace (rc)) {
2896 return ResolveAsTypeOrNamespace (rc, false);
2900 if ((restrictions & MemberLookupRestrictions.NameOfExcluded) == 0 && Name == "nameof")
2901 return new NameOf (this);
2904 if (variable_found) {
2905 rc.Report.Error (841, loc, "A local variable `{0}' cannot be used before it is declared", Name);
2908 var tparams = rc.CurrentTypeParameters;
2909 if (tparams != null) {
2910 if (tparams.Find (Name) != null) {
2911 Error_TypeArgumentsCannotBeUsed (rc, "type parameter", Name, loc);
2916 var ct = rc.CurrentType;
2918 if (ct.MemberDefinition.TypeParametersCount > 0) {
2919 foreach (var ctp in ct.MemberDefinition.TypeParameters) {
2920 if (ctp.Name == Name) {
2921 Error_TypeArgumentsCannotBeUsed (rc, "type parameter", Name, loc);
2927 ct = ct.DeclaringType;
2928 } while (ct != null);
2931 if ((restrictions & MemberLookupRestrictions.InvocableOnly) == 0) {
2932 e = rc.LookupNamespaceOrType (Name, Arity, LookupMode.IgnoreAccessibility, loc);
2934 rc.Report.SymbolRelatedToPreviousError (e.Type);
2935 ErrorIsInaccesible (rc, e.GetSignatureForError (), loc);
2939 var me = MemberLookup (rc, false, rc.CurrentType, Name, Arity, restrictions & ~MemberLookupRestrictions.InvocableOnly, loc) as MemberExpr;
2941 Error_UnexpectedKind (rc, me, "method group", me.KindName, loc);
2942 return ErrorExpression.Instance;
2946 e = rc.LookupNamespaceOrType (Name, -System.Math.Max (1, Arity), LookupMode.Probing, loc);
2948 if (e.Type.Arity != Arity && (restrictions & MemberLookupRestrictions.IgnoreArity) == 0) {
2949 Error_TypeArgumentsCannotBeUsed (rc, e.Type, loc);
2953 if (e is TypeExpr) {
2954 // TypeExpression does not have correct location
2955 if (e is TypeExpression)
2956 e = new TypeExpression (e.Type, loc);
2962 Error_NameDoesNotExist (rc);
2965 return ErrorExpression.Instance;
2968 if (rc.Module.Evaluator != null) {
2969 var fi = rc.Module.Evaluator.LookupField (Name);
2971 return new FieldExpr (fi.Item1, loc);
2979 Expression SimpleNameResolve (ResolveContext ec, Expression right_side)
2981 Expression e = LookupNameExpression (ec, right_side == null ? MemberLookupRestrictions.ReadAccess : MemberLookupRestrictions.None);
2986 if (e is FullNamedExpression && e.eclass != ExprClass.Unresolved) {
2987 Error_UnexpectedKind (ec, e, "variable", e.ExprClassName, loc);
2991 if (right_side != null) {
2992 e = e.ResolveLValue (ec, right_side);
3000 public override object Accept (StructuralVisitor visitor)
3002 return visitor.Visit (this);
3007 /// Represents a namespace or a type. The name of the class was inspired by
3008 /// section 10.8.1 (Fully Qualified Names).
3010 public abstract class FullNamedExpression : Expression
3012 protected override void CloneTo (CloneContext clonectx, Expression target)
3014 // Do nothing, most unresolved type expressions cannot be
3015 // resolved to different type
3018 public override bool ContainsEmitWithAwait ()
3023 public override Expression CreateExpressionTree (ResolveContext ec)
3025 throw new NotSupportedException ("ET");
3028 public abstract FullNamedExpression ResolveAsTypeOrNamespace (IMemberContext mc, bool allowUnboundTypeArguments);
3031 // This is used to resolve the expression as a type, a null
3032 // value will be returned if the expression is not a type
3035 public override TypeSpec ResolveAsType (IMemberContext mc, bool allowUnboundTypeArguments = false)
3037 FullNamedExpression fne = ResolveAsTypeOrNamespace (mc, allowUnboundTypeArguments);
3042 TypeExpr te = fne as TypeExpr;
3044 Error_UnexpectedKind (mc, fne, "type", fne.ExprClassName, loc);
3052 var dep = type.GetMissingDependencies ();
3054 ImportedTypeDefinition.Error_MissingDependency (mc, dep, loc);
3057 if (type.Kind == MemberKind.Void) {
3058 mc.Module.Compiler.Report.Error (673, loc, "System.Void cannot be used from C#. Consider using `void'");
3062 // Obsolete checks cannot be done when resolving base context as they
3063 // require type dependencies to be set but we are in process of resolving them
3065 if (mc is ResolveContext) {
3066 var oa = type.GetAttributeObsolete ();
3067 if (oa != null && !mc.IsObsolete)
3068 AttributeTester.Report_ObsoleteMessage (oa, type.GetSignatureForError (), fne.Location, mc.Module.Compiler.Report);
3075 public override void Emit (EmitContext ec)
3077 throw new InternalErrorException ("FullNamedExpression `{0}' found in resolved tree",
3078 GetSignatureForError ());
3083 /// Expression that evaluates to a type
3085 public abstract class TypeExpr : FullNamedExpression
3087 public sealed override FullNamedExpression ResolveAsTypeOrNamespace (IMemberContext mc, bool allowUnboundTypeArguments)
3093 protected sealed override Expression DoResolve (ResolveContext ec)
3099 public override bool Equals (object obj)
3101 TypeExpr tobj = obj as TypeExpr;
3105 return Type == tobj.Type;
3108 public override int GetHashCode ()
3110 return Type.GetHashCode ();
3115 /// Fully resolved Expression that already evaluated to a type
3117 public class TypeExpression : TypeExpr
3119 public TypeExpression (TypeSpec t, Location l)
3122 eclass = ExprClass.Type;
3126 public sealed override TypeSpec ResolveAsType (IMemberContext mc, bool allowUnboundTypeArguments = false)
3132 public class NamespaceExpression : FullNamedExpression
3134 readonly Namespace ns;
3136 public NamespaceExpression (Namespace ns, Location loc)
3139 this.Type = InternalType.Namespace;
3140 this.eclass = ExprClass.Namespace;
3144 public Namespace Namespace {
3150 protected override Expression DoResolve (ResolveContext rc)
3152 throw new NotImplementedException ();
3155 public override FullNamedExpression ResolveAsTypeOrNamespace (IMemberContext mc, bool allowUnboundTypeArguments)
3160 public void Error_NamespaceDoesNotExist (IMemberContext ctx, string name, int arity, Location loc)
3162 var retval = Namespace.LookupType (ctx, name, arity, LookupMode.IgnoreAccessibility, loc);
3163 if (retval != null) {
3164 // ctx.Module.Compiler.Report.SymbolRelatedToPreviousError (retval.MemberDefinition);
3165 ErrorIsInaccesible (ctx, retval.GetSignatureForError (), loc);
3169 retval = Namespace.LookupType (ctx, name, -System.Math.Max (1, arity), LookupMode.Probing, loc);
3170 if (retval != null) {
3171 Error_TypeArgumentsCannotBeUsed (ctx, retval, loc);
3176 if (arity > 0 && Namespace.TryGetNamespace (name, out ns)) {
3177 Error_TypeArgumentsCannotBeUsed (ctx, ExprClassName, ns.GetSignatureForError (), loc);
3181 string assembly = null;
3182 string possible_name = Namespace.GetSignatureForError () + "." + name;
3184 // Only assembly unique name should be added
3185 switch (possible_name) {
3186 case "System.Drawing":
3187 case "System.Web.Services":
3190 case "System.Configuration":
3191 case "System.Data.Services":
3192 case "System.DirectoryServices":
3194 case "System.Net.Http":
3195 case "System.Numerics":
3196 case "System.Runtime.Caching":
3197 case "System.ServiceModel":
3198 case "System.Transactions":
3199 case "System.Web.Routing":
3200 case "System.Xml.Linq":
3202 assembly = possible_name;
3206 case "System.Linq.Expressions":
3207 assembly = "System.Core";
3210 case "System.Windows.Forms":
3211 case "System.Windows.Forms.Layout":
3212 assembly = "System.Windows.Forms";
3216 assembly = assembly == null ? "an" : "`" + assembly + "'";
3218 if (Namespace is GlobalRootNamespace) {
3219 ctx.Module.Compiler.Report.Error (400, loc,
3220 "The type or namespace name `{0}' could not be found in the global namespace. Are you missing {1} assembly reference?",
3223 ctx.Module.Compiler.Report.Error (234, loc,
3224 "The type or namespace name `{0}' does not exist in the namespace `{1}'. Are you missing {2} assembly reference?",
3225 name, GetSignatureForError (), assembly);
3229 public override string GetSignatureForError ()
3231 return ns.GetSignatureForError ();
3234 public FullNamedExpression LookupTypeOrNamespace (IMemberContext ctx, string name, int arity, LookupMode mode, Location loc)
3236 return ns.LookupTypeOrNamespace (ctx, name, arity, mode, loc);
3239 public override string ToString ()
3241 return Namespace.Name;
3246 /// This class denotes an expression which evaluates to a member
3247 /// of a struct or a class.
3249 public abstract class MemberExpr : Expression, OverloadResolver.IInstanceQualifier
3251 protected bool conditional_access_receiver;
3254 // An instance expression associated with this member, if it's a
3255 // non-static member
3257 public Expression InstanceExpression;
3260 /// The name of this member.
3262 public abstract string Name {
3267 // When base.member is used
3269 public bool IsBase {
3270 get { return InstanceExpression is BaseThis; }
3274 /// Whether this is an instance member.
3276 public abstract bool IsInstance {
3281 /// Whether this is a static member.
3283 public abstract bool IsStatic {
3287 public abstract string KindName {
3291 public bool ConditionalAccess { get; set; }
3293 protected abstract TypeSpec DeclaringType {
3297 TypeSpec OverloadResolver.IInstanceQualifier.InstanceType {
3299 return InstanceExpression.Type;
3304 // Converts best base candidate for virtual method starting from QueriedBaseType
3306 protected MethodSpec CandidateToBaseOverride (ResolveContext rc, MethodSpec method)
3309 // Only when base.member is used and method is virtual
3315 // Overload resulution works on virtual or non-virtual members only (no overrides). That
3316 // means for base.member access we have to find the closest match after we found best candidate
3318 if ((method.Modifiers & (Modifiers.ABSTRACT | Modifiers.VIRTUAL | Modifiers.OVERRIDE)) != 0) {
3320 // The method could already be what we are looking for
3322 TypeSpec[] targs = null;
3323 if (method.DeclaringType != InstanceExpression.Type) {
3325 // Candidate can have inflated MVAR parameters and we need to find
3326 // base match for original definition not inflated parameter types
3328 var parameters = method.Parameters;
3329 if (method.Arity > 0) {
3330 parameters = ((IParametersMember) method.MemberDefinition).Parameters;
3331 var inflated = method.DeclaringType as InflatedTypeSpec;
3332 if (inflated != null) {
3333 parameters = parameters.Inflate (inflated.CreateLocalInflator (rc));
3337 var filter = new MemberFilter (method.Name, method.Arity, MemberKind.Method, parameters, null);
3338 var base_override = MemberCache.FindMember (InstanceExpression.Type, filter, BindingRestriction.InstanceOnly | BindingRestriction.OverrideOnly) as MethodSpec;
3339 if (base_override != null && base_override.DeclaringType != method.DeclaringType) {
3340 if (base_override.IsGeneric)
3341 targs = method.TypeArguments;
3343 method = base_override;
3348 // When base access is used inside anonymous method/iterator/etc we need to
3349 // get back to the context of original type. We do it by emiting proxy
3350 // method in original class and rewriting base call to this compiler
3351 // generated method call which does the actual base invocation. This may
3352 // introduce redundant storey but with `this' only but it's tricky to avoid
3353 // at this stage as we don't know what expressions follow base
3355 if (rc.CurrentAnonymousMethod != null) {
3356 if (targs == null && method.IsGeneric) {
3357 targs = method.TypeArguments;
3358 method = method.GetGenericMethodDefinition ();
3361 if (method.Parameters.HasArglist)
3362 throw new NotImplementedException ("__arglist base call proxy");
3364 method = rc.CurrentMemberDefinition.Parent.PartialContainer.CreateHoistedBaseCallProxy (rc, method);
3366 // Ideally this should apply to any proxy rewrite but in the case of unary mutators on
3367 // get/set member expressions second call would fail to proxy because left expression
3368 // would be of 'this' and not 'base' because we share InstanceExpression for get/set
3369 // FIXME: The async check is another hack but will probably fail with mutators
3370 if (rc.CurrentType.IsStruct || rc.CurrentAnonymousMethod.Storey is AsyncTaskStorey)
3371 InstanceExpression = new This (loc).Resolve (rc);
3375 method = method.MakeGenericMethod (rc, targs);
3379 // Only base will allow this invocation to happen.
3381 if (method.IsAbstract) {
3382 rc.Report.SymbolRelatedToPreviousError (method);
3383 Error_CannotCallAbstractBase (rc, method.GetSignatureForError ());
3389 protected void CheckProtectedMemberAccess (ResolveContext rc, MemberSpec member)
3391 if (InstanceExpression == null)
3394 if ((member.Modifiers & Modifiers.PROTECTED) != 0 && !(InstanceExpression is This)) {
3395 if (!CheckProtectedMemberAccess (rc, member, InstanceExpression.Type)) {
3396 Error_ProtectedMemberAccess (rc, member, InstanceExpression.Type, loc);
3401 bool OverloadResolver.IInstanceQualifier.CheckProtectedMemberAccess (ResolveContext rc, MemberSpec member)
3403 if (InstanceExpression == null)
3406 return InstanceExpression is This || CheckProtectedMemberAccess (rc, member, InstanceExpression.Type);
3409 public static bool CheckProtectedMemberAccess<T> (ResolveContext rc, T member, TypeSpec qualifier) where T : MemberSpec
3411 var ct = rc.CurrentType;
3412 if (ct == qualifier)
3415 if ((member.Modifiers & Modifiers.INTERNAL) != 0 && member.DeclaringType.MemberDefinition.IsInternalAsPublic (ct.MemberDefinition.DeclaringAssembly))
3418 qualifier = qualifier.GetDefinition ();
3419 if (ct != qualifier && !IsSameOrBaseQualifier (ct, qualifier)) {
3426 public override bool ContainsEmitWithAwait ()
3428 return InstanceExpression != null && InstanceExpression.ContainsEmitWithAwait ();
3431 public override bool HasConditionalAccess ()
3433 return ConditionalAccess || (InstanceExpression != null && InstanceExpression.HasConditionalAccess ());
3436 static bool IsSameOrBaseQualifier (TypeSpec type, TypeSpec qtype)
3439 type = type.GetDefinition ();
3441 if (type == qtype || TypeManager.IsFamilyAccessible (qtype, type))
3444 type = type.DeclaringType;
3445 } while (type != null);
3450 protected void DoBestMemberChecks<T> (ResolveContext rc, T member) where T : MemberSpec, IInterfaceMemberSpec
3452 if (InstanceExpression != null) {
3453 InstanceExpression = InstanceExpression.Resolve (rc);
3454 CheckProtectedMemberAccess (rc, member);
3457 if (member.MemberType.IsPointer && !rc.IsUnsafe) {
3458 UnsafeError (rc, loc);
3461 var dep = member.GetMissingDependencies ();
3463 ImportedTypeDefinition.Error_MissingDependency (rc, dep, loc);
3466 member.CheckObsoleteness (rc, loc);
3468 if (!(member is FieldSpec))
3469 member.MemberDefinition.SetIsUsed ();
3472 protected virtual void Error_CannotCallAbstractBase (ResolveContext rc, string name)
3474 rc.Report.Error (205, loc, "Cannot call an abstract base member `{0}'", name);
3477 public static void Error_ProtectedMemberAccess (ResolveContext rc, MemberSpec member, TypeSpec qualifier, Location loc)
3479 rc.Report.SymbolRelatedToPreviousError (member);
3480 rc.Report.Error (1540, loc,
3481 "Cannot access protected member `{0}' via a qualifier of type `{1}'. The qualifier must be of type `{2}' or derived from it",
3482 member.GetSignatureForError (), qualifier.GetSignatureForError (), rc.CurrentType.GetSignatureForError ());
3485 public override void FlowAnalysis (FlowAnalysisContext fc)
3487 if (InstanceExpression != null) {
3488 InstanceExpression.FlowAnalysis (fc);
3492 protected void ResolveConditionalAccessReceiver (ResolveContext rc)
3494 if (!rc.HasSet (ResolveContext.Options.DontSetConditionalAccessReceiver) && HasConditionalAccess ()) {
3495 conditional_access_receiver = true;
3499 public bool ResolveInstanceExpression (ResolveContext rc, Expression rhs)
3501 if (!ResolveInstanceExpressionCore (rc, rhs))
3505 // Check intermediate value modification which won't have any effect
3507 if (rhs != null && TypeSpec.IsValueType (InstanceExpression.Type)) {
3508 var fexpr = InstanceExpression as FieldExpr;
3509 if (fexpr != null) {
3510 if (!fexpr.Spec.IsReadOnly || rc.HasAny (ResolveContext.Options.FieldInitializerScope | ResolveContext.Options.ConstructorScope))
3513 if (fexpr.IsStatic) {
3514 rc.Report.Error (1650, loc, "Fields of static readonly field `{0}' cannot be assigned to (except in a static constructor or a variable initializer)",
3515 fexpr.GetSignatureForError ());
3517 rc.Report.Error (1648, loc, "Members of readonly field `{0}' cannot be modified (except in a constructor or a variable initializer)",
3518 fexpr.GetSignatureForError ());
3524 if (InstanceExpression is PropertyExpr || InstanceExpression is IndexerExpr || InstanceExpression is Invocation) {
3525 if (rc.CurrentInitializerVariable != null) {
3526 rc.Report.Error (1918, loc, "Members of value type `{0}' cannot be assigned using a property `{1}' object initializer",
3527 InstanceExpression.Type.GetSignatureForError (), InstanceExpression.GetSignatureForError ());
3529 rc.Report.Error (1612, loc,
3530 "Cannot modify a value type return value of `{0}'. Consider storing the value in a temporary variable",
3531 InstanceExpression.GetSignatureForError ());
3537 var lvr = InstanceExpression as LocalVariableReference;
3540 if (!lvr.local_info.IsReadonly)
3543 rc.Report.Error (1654, loc, "Cannot assign to members of `{0}' because it is a `{1}'",
3544 InstanceExpression.GetSignatureForError (), lvr.local_info.GetReadOnlyContext ());
3551 bool ResolveInstanceExpressionCore (ResolveContext rc, Expression rhs)
3554 if (InstanceExpression != null) {
3555 if (InstanceExpression is TypeExpr) {
3556 var t = InstanceExpression.Type;
3558 t.CheckObsoleteness (rc, loc);
3560 t = t.DeclaringType;
3561 } while (t != null);
3563 var runtime_expr = InstanceExpression as RuntimeValueExpression;
3564 if (runtime_expr == null || !runtime_expr.IsSuggestionOnly) {
3565 rc.Report.Error (176, loc,
3566 "Static member `{0}' cannot be accessed with an instance reference, qualify it with a type name instead",
3567 GetSignatureForError ());
3571 InstanceExpression = null;
3577 if (InstanceExpression == null || InstanceExpression is TypeExpr) {
3578 if (InstanceExpression != null || !This.IsThisAvailable (rc, true)) {
3579 if (rc.HasSet (ResolveContext.Options.FieldInitializerScope)) {
3580 rc.Report.Error (236, loc,
3581 "A field initializer cannot reference the nonstatic field, method, or property `{0}'",
3582 GetSignatureForError ());
3584 var fe = this as FieldExpr;
3585 if (fe != null && fe.Spec.MemberDefinition is PrimaryConstructorField) {
3586 if (rc.HasSet (ResolveContext.Options.BaseInitializer)) {
3587 rc.Report.Error (9005, loc, "Constructor initializer cannot access primary constructor parameters");
3589 rc.Report.Error (9006, loc, "An object reference is required to access primary constructor parameter `{0}'",
3593 rc.Report.Error (120, loc,
3594 "An object reference is required to access non-static member `{0}'",
3595 GetSignatureForError ());
3599 InstanceExpression = new CompilerGeneratedThis (rc.CurrentType, loc).Resolve (rc);
3603 if (!TypeManager.IsFamilyAccessible (rc.CurrentType, DeclaringType)) {
3604 rc.Report.Error (38, loc,
3605 "Cannot access a nonstatic member of outer type `{0}' via nested type `{1}'",
3606 DeclaringType.GetSignatureForError (), rc.CurrentType.GetSignatureForError ());
3609 InstanceExpression = new This (loc).Resolve (rc);
3613 var me = InstanceExpression as MemberExpr;
3615 me.ResolveInstanceExpressionCore (rc, rhs);
3617 var fe = me as FieldExpr;
3618 if (fe != null && fe.IsMarshalByRefAccess (rc)) {
3619 rc.Report.SymbolRelatedToPreviousError (me.DeclaringType);
3620 rc.Report.Warning (1690, 1, loc,
3621 "Cannot call methods, properties, or indexers on `{0}' because it is a value type member of a marshal-by-reference class",
3622 me.GetSignatureForError ());
3629 // Additional checks for l-value member access
3632 if (InstanceExpression is UnboxCast) {
3633 rc.Report.Error (445, InstanceExpression.Location, "Cannot modify the result of an unboxing conversion");
3640 public virtual MemberExpr ResolveMemberAccess (ResolveContext ec, Expression left, SimpleName original)
3642 if (left != null && !ConditionalAccess && !ec.HasSet (ResolveContext.Options.NameOfScope) && left.IsNull && TypeSpec.IsReferenceType (left.Type)) {
3643 ec.Report.Warning (1720, 1, left.Location,
3644 "Expression will always cause a `{0}'", "System.NullReferenceException");
3647 InstanceExpression = left;
3651 public virtual void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
3656 protected void EmitInstance (EmitContext ec, bool prepare_for_load)
3658 var inst = new InstanceEmitter (InstanceExpression, TypeSpec.IsValueType (InstanceExpression.Type));
3659 inst.Emit (ec, ConditionalAccess);
3661 if (prepare_for_load)
3662 ec.Emit (OpCodes.Dup);
3665 public abstract void SetTypeArguments (ResolveContext ec, TypeArguments ta);
3668 public class ExtensionMethodCandidates
3670 readonly NamespaceContainer container;
3671 readonly IList<MethodSpec> methods;
3673 readonly IMemberContext context;
3675 public ExtensionMethodCandidates (IMemberContext context, IList<MethodSpec> methods, NamespaceContainer nsContainer, int lookupIndex)
3677 this.context = context;
3678 this.methods = methods;
3679 this.container = nsContainer;
3680 this.index = lookupIndex;
3683 public NamespaceContainer Container {
3689 public IMemberContext Context {
3695 public int LookupIndex {
3701 public IList<MethodSpec> Methods {
3709 // Represents a group of extension method candidates for whole namespace
3711 class ExtensionMethodGroupExpr : MethodGroupExpr, OverloadResolver.IErrorHandler
3713 ExtensionMethodCandidates candidates;
3714 public Expression ExtensionExpression;
3716 public ExtensionMethodGroupExpr (ExtensionMethodCandidates candidates, Expression extensionExpr, Location loc)
3717 : base (candidates.Methods.Cast<MemberSpec>().ToList (), extensionExpr.Type, loc)
3719 this.candidates = candidates;
3720 this.ExtensionExpression = extensionExpr;
3723 public override bool IsStatic {
3724 get { return true; }
3728 // For extension methodgroup we are not looking for base members but parent
3729 // namespace extension methods
3731 public override IList<MemberSpec> GetBaseMembers (TypeSpec type)
3733 // TODO: candidates are null only when doing error reporting, that's
3734 // incorrect. We have to discover same extension methods in error mode
3735 if (candidates == null)
3738 int arity = type_arguments == null ? 0 : type_arguments.Count;
3740 candidates = candidates.Container.LookupExtensionMethod (candidates.Context, Name, arity, candidates.LookupIndex);
3741 if (candidates == null)
3744 return candidates.Methods.Cast<MemberSpec> ().ToList ();
3747 public static bool IsExtensionTypeCompatible (TypeSpec argType, TypeSpec extensionType)
3750 // Indentity, implicit reference or boxing conversion must exist for the extension parameter
3752 // LAMESPEC: or implicit type parameter conversion
3754 return argType == extensionType ||
3755 TypeSpecComparer.IsEqual (argType, extensionType) ||
3756 Convert.ImplicitReferenceConversionExists (argType, extensionType, false) ||
3757 Convert.ImplicitBoxingConversion (null, argType, extensionType) != null;
3760 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
3762 rc.Report.Error (8093, expr.Location, "An argument to nameof operator cannot be extension method group");
3765 public override MethodGroupExpr LookupExtensionMethod (ResolveContext rc)
3767 // We are already here
3771 public override MethodGroupExpr OverloadResolve (ResolveContext ec, ref Arguments arguments, OverloadResolver.IErrorHandler ehandler, OverloadResolver.Restrictions restr)
3773 if (arguments == null)
3774 arguments = new Arguments (1);
3776 ExtensionExpression = ExtensionExpression.Resolve (ec);
3777 if (ExtensionExpression == null)
3780 var cand = candidates;
3781 var atype = ConditionalAccess ? Argument.AType.ExtensionTypeConditionalAccess : Argument.AType.ExtensionType;
3782 arguments.Insert (0, new Argument (ExtensionExpression, atype));
3783 var res = base.OverloadResolve (ec, ref arguments, ehandler ?? this, restr);
3785 // Restore candidates in case we are running in probing mode
3788 // Store resolved argument and restore original arguments
3790 // Clean-up modified arguments for error reporting
3791 arguments.RemoveAt (0);
3795 var me = ExtensionExpression as MemberExpr;
3797 me.ResolveInstanceExpression (ec, null);
3798 var fe = me as FieldExpr;
3800 fe.Spec.MemberDefinition.SetIsUsed ();
3803 InstanceExpression = null;
3807 #region IErrorHandler Members
3809 bool OverloadResolver.IErrorHandler.AmbiguousCandidates (ResolveContext rc, MemberSpec best, MemberSpec ambiguous)
3814 bool OverloadResolver.IErrorHandler.ArgumentMismatch (ResolveContext rc, MemberSpec best, Argument arg, int index)
3816 rc.Report.SymbolRelatedToPreviousError (best);
3819 rc.Report.Error (1929, loc,
3820 "Type `{0}' does not contain a member `{1}' and the best extension method overload `{2}' requires an instance of type `{3}'",
3821 queried_type.GetSignatureForError (), Name, best.GetSignatureForError (), ((MethodSpec)best).Parameters.ExtensionMethodType.GetSignatureForError ());
3823 rc.Report.Error (1928, loc,
3824 "Type `{0}' does not contain a member `{1}' and the best extension method overload `{2}' has some invalid arguments",
3825 queried_type.GetSignatureForError (), Name, best.GetSignatureForError ());
3831 bool OverloadResolver.IErrorHandler.NoArgumentMatch (ResolveContext rc, MemberSpec best)
3836 bool OverloadResolver.IErrorHandler.TypeInferenceFailed (ResolveContext rc, MemberSpec best)
3845 /// MethodGroupExpr represents a group of method candidates which
3846 /// can be resolved to the best method overload
3848 public class MethodGroupExpr : MemberExpr, OverloadResolver.IBaseMembersProvider
3850 static readonly MemberSpec[] Excluded = new MemberSpec[0];
3852 protected IList<MemberSpec> Methods;
3853 MethodSpec best_candidate;
3854 TypeSpec best_candidate_return;
3855 protected TypeArguments type_arguments;
3857 SimpleName simple_name;
3858 protected TypeSpec queried_type;
3860 public MethodGroupExpr (IList<MemberSpec> mi, TypeSpec type, Location loc)
3864 this.type = InternalType.MethodGroup;
3866 eclass = ExprClass.MethodGroup;
3867 queried_type = type;
3870 public MethodGroupExpr (MethodSpec m, TypeSpec type, Location loc)
3871 : this (new MemberSpec[] { m }, type, loc)
3877 public MethodSpec BestCandidate {
3879 return best_candidate;
3883 public TypeSpec BestCandidateReturnType {
3885 return best_candidate_return;
3889 public IList<MemberSpec> Candidates {
3895 protected override TypeSpec DeclaringType {
3897 return queried_type;
3901 public bool IsConditionallyExcluded {
3903 return Methods == Excluded;
3907 public override bool IsInstance {
3909 if (best_candidate != null)
3910 return !best_candidate.IsStatic;
3916 public override bool IsSideEffectFree {
3918 return InstanceExpression == null || InstanceExpression.IsSideEffectFree;
3922 public override bool IsStatic {
3924 if (best_candidate != null)
3925 return best_candidate.IsStatic;
3931 public override string KindName {
3932 get { return "method"; }
3935 public override string Name {
3937 if (best_candidate != null)
3938 return best_candidate.Name;
3941 return Methods.First ().Name;
3948 // When best candidate is already know this factory can be used
3949 // to avoid expensive overload resolution to be called
3951 // NOTE: InstanceExpression has to be set manually
3953 public static MethodGroupExpr CreatePredefined (MethodSpec best, TypeSpec queriedType, Location loc)
3955 return new MethodGroupExpr (best, queriedType, loc) {
3956 best_candidate = best,
3957 best_candidate_return = best.ReturnType
3961 public override string GetSignatureForError ()
3963 if (best_candidate != null)
3964 return best_candidate.GetSignatureForError ();
3966 return Methods.First ().GetSignatureForError ();
3969 public override Expression CreateExpressionTree (ResolveContext ec)
3971 if (best_candidate == null) {
3972 ec.Report.Error (1953, loc, "An expression tree cannot contain an expression with method group");
3976 if (IsConditionallyExcluded)
3977 ec.Report.Error (765, loc,
3978 "Partial methods with only a defining declaration or removed conditional methods cannot be used in an expression tree");
3980 if (ConditionalAccess)
3981 Error_NullShortCircuitInsideExpressionTree (ec);
3983 return new TypeOfMethod (best_candidate, loc);
3986 protected override Expression DoResolve (ResolveContext ec)
3988 this.eclass = ExprClass.MethodGroup;
3990 if (InstanceExpression != null) {
3991 InstanceExpression = InstanceExpression.Resolve (ec);
3992 if (InstanceExpression == null)
3999 public override void Emit (EmitContext ec)
4001 throw new NotSupportedException ();
4004 public void EmitCall (EmitContext ec, Arguments arguments, bool statement)
4006 var call = new CallEmitter ();
4007 call.InstanceExpression = InstanceExpression;
4008 call.ConditionalAccess = ConditionalAccess;
4011 call.EmitStatement (ec, best_candidate, arguments, loc);
4013 call.Emit (ec, best_candidate, arguments, loc);
4016 public void EmitCall (EmitContext ec, Arguments arguments, TypeSpec conditionalAccessReceiver, bool statement)
4018 var ca = ec.ConditionalAccess;
4019 ec.ConditionalAccess = new ConditionalAccessContext (conditionalAccessReceiver, ec.DefineLabel ()) {
4020 Statement = statement
4023 EmitCall (ec, arguments, statement);
4025 ec.CloseConditionalAccess (!statement && best_candidate_return != conditionalAccessReceiver && conditionalAccessReceiver.IsNullableType ? conditionalAccessReceiver : null);
4026 ec.ConditionalAccess = ca;
4029 public override void Error_ValueCannotBeConverted (ResolveContext ec, TypeSpec target, bool expl)
4031 if (target != InternalType.ErrorType) {
4032 ec.Report.Error (428, loc, "Cannot convert method group `{0}' to non-delegate type `{1}'. Consider using parentheses to invoke the method",
4033 Name, target.GetSignatureForError ());
4037 public bool HasAccessibleCandidate (ResolveContext rc)
4039 foreach (var candidate in Candidates) {
4040 if (candidate.IsAccessible (rc))
4047 public static bool IsExtensionMethodArgument (Expression expr)
4050 // LAMESPEC: No details about which expressions are not allowed
4052 return !(expr is TypeExpr) && !(expr is BaseThis);
4056 /// Find the Applicable Function Members (7.4.2.1)
4058 /// me: Method Group expression with the members to select.
4059 /// it might contain constructors or methods (or anything
4060 /// that maps to a method).
4062 /// Arguments: ArrayList containing resolved Argument objects.
4064 /// loc: The location if we want an error to be reported, or a Null
4065 /// location for "probing" purposes.
4067 /// Returns: The MethodBase (either a ConstructorInfo or a MethodInfo)
4068 /// that is the best match of me on Arguments.
4071 public virtual MethodGroupExpr OverloadResolve (ResolveContext ec, ref Arguments args, OverloadResolver.IErrorHandler cerrors, OverloadResolver.Restrictions restr)
4073 // TODO: causes issues with probing mode, remove explicit Kind check
4074 if (best_candidate != null && best_candidate.Kind == MemberKind.Destructor)
4077 var r = new OverloadResolver (Methods, type_arguments, restr, loc);
4078 if ((restr & OverloadResolver.Restrictions.NoBaseMembers) == 0) {
4079 r.BaseMembersProvider = this;
4080 r.InstanceQualifier = this;
4083 if (cerrors != null)
4084 r.CustomErrors = cerrors;
4086 // TODO: When in probing mode do IsApplicable only and when called again do VerifyArguments for full error reporting
4087 best_candidate = r.ResolveMember<MethodSpec> (ec, ref args);
4088 if (best_candidate == null) {
4089 if (!r.BestCandidateIsDynamic)
4092 if (simple_name != null && ec.IsStatic)
4093 InstanceExpression = ProbeIdenticalTypeName (ec, InstanceExpression, simple_name);
4098 // Overload resolver had to create a new method group, all checks bellow have already been executed
4099 if (r.BestCandidateNewMethodGroup != null)
4100 return r.BestCandidateNewMethodGroup;
4102 if (best_candidate.Kind == MemberKind.Method && (restr & OverloadResolver.Restrictions.ProbingOnly) == 0) {
4103 if (InstanceExpression != null) {
4104 if (best_candidate.IsExtensionMethod && args[0].Expr == InstanceExpression) {
4105 InstanceExpression = null;
4107 if (simple_name != null && best_candidate.IsStatic) {
4108 InstanceExpression = ProbeIdenticalTypeName (ec, InstanceExpression, simple_name);
4111 InstanceExpression.Resolve (ec, ResolveFlags.VariableOrValue | ResolveFlags.MethodGroup | ResolveFlags.Type);
4115 ResolveInstanceExpression (ec, null);
4118 var base_override = CandidateToBaseOverride (ec, best_candidate);
4119 if (base_override == best_candidate) {
4120 best_candidate_return = r.BestCandidateReturnType;
4122 best_candidate = base_override;
4123 best_candidate_return = best_candidate.ReturnType;
4126 if (best_candidate.IsGeneric && (restr & OverloadResolver.Restrictions.ProbingOnly) == 0 && TypeParameterSpec.HasAnyTypeParameterConstrained (best_candidate.GenericDefinition)) {
4127 ConstraintChecker cc = new ConstraintChecker (ec);
4128 cc.CheckAll (best_candidate.GetGenericMethodDefinition (), best_candidate.TypeArguments, best_candidate.Constraints, loc);
4132 // Additional check for possible imported base override method which
4133 // could not be done during IsOverrideMethodBaseTypeAccessible
4135 if (best_candidate.IsVirtual && (best_candidate.DeclaringType.Modifiers & Modifiers.PROTECTED) != 0 &&
4136 best_candidate.MemberDefinition.IsImported && !best_candidate.DeclaringType.IsAccessible (ec)) {
4137 ec.Report.SymbolRelatedToPreviousError (best_candidate);
4138 ErrorIsInaccesible (ec, best_candidate.GetSignatureForError (), loc);
4141 // Speed up the check by not doing it on disallowed targets
4142 if (best_candidate_return.Kind == MemberKind.Void && best_candidate.IsConditionallyExcluded (ec))
4148 public override MemberExpr ResolveMemberAccess (ResolveContext ec, Expression left, SimpleName original)
4150 var fe = left as FieldExpr;
4153 // Using method-group on struct fields makes the struct assigned. I am not sure
4154 // why but that's what .net does
4156 fe.Spec.MemberDefinition.SetIsAssigned ();
4159 simple_name = original;
4160 return base.ResolveMemberAccess (ec, left, original);
4163 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
4165 if (!HasAccessibleCandidate (rc)) {
4166 ErrorIsInaccesible (rc, expr.GetSignatureForError (), loc);
4169 if (expr.HasTypeArguments) {
4170 rc.Report.Error (8084, expr.Location, "An argument to nameof operator cannot be method group with type arguments");
4174 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
4176 type_arguments = ta;
4179 #region IBaseMembersProvider Members
4181 public virtual IList<MemberSpec> GetBaseMembers (TypeSpec type)
4183 var baseType = type.BaseType;
4185 IList<MemberSpec> members = baseType == null ? null : MemberCache.FindMembers (baseType, Methods [0].Name, false);
4187 if (members == null && !type.IsInterface) {
4188 var tps = queried_type as TypeParameterSpec;
4190 members = MemberCache.FindInterfaceMembers (tps, Methods [0].Name);
4196 public IParametersMember GetOverrideMemberParameters (MemberSpec member)
4198 if (queried_type == member.DeclaringType)
4201 return MemberCache.FindMember (queried_type, new MemberFilter ((MethodSpec) member),
4202 BindingRestriction.InstanceOnly | BindingRestriction.OverrideOnly) as IParametersMember;
4206 // Extension methods lookup after ordinary methods candidates failed to apply
4208 public virtual MethodGroupExpr LookupExtensionMethod (ResolveContext rc)
4210 if (InstanceExpression == null || InstanceExpression.eclass == ExprClass.Type)
4213 if (!IsExtensionMethodArgument (InstanceExpression))
4216 int arity = type_arguments == null ? 0 : type_arguments.Count;
4217 var methods = rc.LookupExtensionMethod (Methods[0].Name, arity);
4218 if (methods == null)
4221 var emg = new ExtensionMethodGroupExpr (methods, InstanceExpression, loc);
4222 emg.SetTypeArguments (rc, type_arguments);
4223 emg.ConditionalAccess = ConditionalAccess;
4230 struct ConstructorInstanceQualifier : OverloadResolver.IInstanceQualifier
4232 public ConstructorInstanceQualifier (TypeSpec type)
4235 InstanceType = type;
4238 public TypeSpec InstanceType { get; private set; }
4240 public bool CheckProtectedMemberAccess (ResolveContext rc, MemberSpec member)
4242 return MemberExpr.CheckProtectedMemberAccess (rc, member, InstanceType);
4246 public struct OverloadResolver
4249 public enum Restrictions
4253 ProbingOnly = 1 << 1,
4254 CovariantDelegate = 1 << 2,
4255 NoBaseMembers = 1 << 3,
4256 BaseMembersIncluded = 1 << 4,
4257 GetEnumeratorLookup = 1 << 5
4260 public interface IBaseMembersProvider
4262 IList<MemberSpec> GetBaseMembers (TypeSpec baseType);
4263 IParametersMember GetOverrideMemberParameters (MemberSpec member);
4264 MethodGroupExpr LookupExtensionMethod (ResolveContext rc);
4267 public interface IErrorHandler
4269 bool AmbiguousCandidates (ResolveContext rc, MemberSpec best, MemberSpec ambiguous);
4270 bool ArgumentMismatch (ResolveContext rc, MemberSpec best, Argument a, int index);
4271 bool NoArgumentMatch (ResolveContext rc, MemberSpec best);
4272 bool TypeInferenceFailed (ResolveContext rc, MemberSpec best);
4275 public interface IInstanceQualifier
4277 TypeSpec InstanceType { get; }
4278 bool CheckProtectedMemberAccess (ResolveContext rc, MemberSpec member);
4281 sealed class NoBaseMembers : IBaseMembersProvider
4283 public static readonly IBaseMembersProvider Instance = new NoBaseMembers ();
4285 public IList<MemberSpec> GetBaseMembers (TypeSpec baseType)
4290 public IParametersMember GetOverrideMemberParameters (MemberSpec member)
4295 public MethodGroupExpr LookupExtensionMethod (ResolveContext rc)
4301 struct AmbiguousCandidate
4303 public readonly MemberSpec Member;
4304 public readonly bool Expanded;
4305 public readonly AParametersCollection Parameters;
4307 public AmbiguousCandidate (MemberSpec member, AParametersCollection parameters, bool expanded)
4310 Parameters = parameters;
4311 Expanded = expanded;
4316 IList<MemberSpec> members;
4317 TypeArguments type_arguments;
4318 IBaseMembersProvider base_provider;
4319 IErrorHandler custom_errors;
4320 IInstanceQualifier instance_qualifier;
4321 Restrictions restrictions;
4322 MethodGroupExpr best_candidate_extension_group;
4323 TypeSpec best_candidate_return_type;
4325 SessionReportPrinter lambda_conv_msgs;
4327 public OverloadResolver (IList<MemberSpec> members, Restrictions restrictions, Location loc)
4328 : this (members, null, restrictions, loc)
4332 public OverloadResolver (IList<MemberSpec> members, TypeArguments targs, Restrictions restrictions, Location loc)
4335 if (members == null || members.Count == 0)
4336 throw new ArgumentException ("empty members set");
4338 this.members = members;
4340 type_arguments = targs;
4341 this.restrictions = restrictions;
4342 if (IsDelegateInvoke)
4343 this.restrictions |= Restrictions.NoBaseMembers;
4345 base_provider = NoBaseMembers.Instance;
4350 public IBaseMembersProvider BaseMembersProvider {
4352 return base_provider;
4355 base_provider = value;
4359 public bool BestCandidateIsDynamic { get; set; }
4362 // Best candidate was found in newly created MethodGroupExpr, used by extension methods
4364 public MethodGroupExpr BestCandidateNewMethodGroup {
4366 return best_candidate_extension_group;
4371 // Return type can be different between best candidate and closest override
4373 public TypeSpec BestCandidateReturnType {
4375 return best_candidate_return_type;
4379 public IErrorHandler CustomErrors {
4381 return custom_errors;
4384 custom_errors = value;
4388 TypeSpec DelegateType {
4390 if ((restrictions & Restrictions.DelegateInvoke) == 0)
4391 throw new InternalErrorException ("Not running in delegate mode", loc);
4393 return members [0].DeclaringType;
4397 public IInstanceQualifier InstanceQualifier {
4399 return instance_qualifier;
4402 instance_qualifier = value;
4406 bool IsProbingOnly {
4408 return (restrictions & Restrictions.ProbingOnly) != 0;
4412 bool IsDelegateInvoke {
4414 return (restrictions & Restrictions.DelegateInvoke) != 0;
4421 // 7.4.3.3 Better conversion from expression
4422 // Returns : 1 if a->p is better,
4423 // 2 if a->q is better,
4424 // 0 if neither is better
4426 static int BetterExpressionConversion (ResolveContext ec, Argument a, TypeSpec p, TypeSpec q)
4428 TypeSpec argument_type = a.Type;
4431 // Exactly matching Expression phase
4435 // If argument is an anonymous function
4437 if (argument_type == InternalType.AnonymousMethod && ec.Module.Compiler.Settings.Version > LanguageVersion.ISO_2) {
4439 // p and q are delegate types or expression tree types
4441 if (p.IsExpressionTreeType || q.IsExpressionTreeType) {
4442 if (q.MemberDefinition != p.MemberDefinition) {
4447 // Uwrap delegate from Expression<T>
4449 q = TypeManager.GetTypeArguments (q) [0];
4450 p = TypeManager.GetTypeArguments (p) [0];
4453 var p_m = Delegate.GetInvokeMethod (p);
4454 var q_m = Delegate.GetInvokeMethod (q);
4457 // With identical parameter lists
4459 if (!TypeSpecComparer.Equals (p_m.Parameters.Types, q_m.Parameters.Types))
4467 // if p is void returning, and q has a return type Y, then C2 is the better conversion.
4469 if (p.Kind == MemberKind.Void) {
4470 return q.Kind != MemberKind.Void ? 2 : 0;
4474 // if p has a return type Y, and q is void returning, then C1 is the better conversion.
4476 if (q.Kind == MemberKind.Void) {
4477 return p.Kind != MemberKind.Void ? 1 : 0;
4480 var am = (AnonymousMethodExpression)a.Expr;
4483 // When anonymous method is an asynchronous, and P has a return type Task<Y1>, and Q has a return type Task<Y2>
4484 // better conversion is performed between underlying types Y1 and Y2
4486 if (p.IsGenericTask || q.IsGenericTask) {
4487 if (am.Block.IsAsync && p.IsGenericTask && q.IsGenericTask) {
4488 q = q.TypeArguments [0];
4489 p = p.TypeArguments [0];
4495 // An inferred return type X exists for E in the context of the parameter list, and
4496 // an identity conversion exists from X to the return type of D
4498 var inferred_type = am.InferReturnType (ec, null, orig_q);
4499 if (inferred_type != null) {
4500 if (inferred_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic)
4501 inferred_type = ec.BuiltinTypes.Object;
4503 if (inferred_type == p)
4506 if (inferred_type == q)
4512 if (argument_type == p)
4515 if (argument_type == q)
4518 return IsBetterConversionTarget (ec, p, q);
4521 static int IsBetterConversionTarget (ResolveContext rc, TypeSpec p, TypeSpec q)
4523 if ((p.Kind == MemberKind.Delegate || p.IsExpressionTreeType) && (q.Kind == MemberKind.Delegate || q.IsExpressionTreeType)) {
4525 if (p.Kind != MemberKind.Delegate) {
4526 p = TypeManager.GetTypeArguments (p) [0];
4529 if (q.Kind != MemberKind.Delegate) {
4530 q = TypeManager.GetTypeArguments (q) [0];
4533 var p_m = Delegate.GetInvokeMethod (p);
4534 var q_m = Delegate.GetInvokeMethod (q);
4540 // if p is void returning, and q has a return type Y, then C2 is the better conversion.
4542 if (p.Kind == MemberKind.Void) {
4543 return q.Kind != MemberKind.Void ? 2 : 0;
4547 // if p has a return type Y, and q is void returning, then C1 is the better conversion.
4549 if (q.Kind == MemberKind.Void) {
4550 return p.Kind != MemberKind.Void ? 1 : 0;
4553 return IsBetterConversionTarget (rc, p, q);
4556 if (p.IsGenericTask && q.IsGenericTask) {
4557 q = q.TypeArguments [0];
4558 p = p.TypeArguments [0];
4559 return IsBetterConversionTarget (rc, p, q);
4563 if (p.IsNullableType) {
4564 p = Nullable.NullableInfo.GetUnderlyingType (p);
4565 if (!BuiltinTypeSpec.IsPrimitiveTypeOrDecimal (p))
4566 return BetterTypeConversionImplicitConversion (rc, p_orig, q);
4569 // Spec expects implicit conversion check between p and q, q and p
4570 // to be done before nullable unwrapping but that's expensive operation.
4572 // Extra manual tweak is needed because BetterTypeConversion works on
4580 if (q.IsNullableType) {
4581 q = Nullable.NullableInfo.GetUnderlyingType (q);
4582 if (!BuiltinTypeSpec.IsPrimitiveTypeOrDecimal (q))
4583 return BetterTypeConversionImplicitConversion (rc, p_orig, q_orig);
4589 return BetterTypeConversion (rc, p, q);
4593 // 7.4.3.4 Better conversion from type
4595 public static int BetterTypeConversion (ResolveContext ec, TypeSpec p, TypeSpec q)
4597 if (p == null || q == null)
4598 throw new InternalErrorException ("BetterTypeConversion got a null conversion");
4600 switch (p.BuiltinType) {
4601 case BuiltinTypeSpec.Type.Int:
4602 if (q.BuiltinType == BuiltinTypeSpec.Type.UInt || q.BuiltinType == BuiltinTypeSpec.Type.ULong)
4605 case BuiltinTypeSpec.Type.Long:
4606 if (q.BuiltinType == BuiltinTypeSpec.Type.ULong)
4609 case BuiltinTypeSpec.Type.SByte:
4610 switch (q.BuiltinType) {
4611 case BuiltinTypeSpec.Type.Byte:
4612 case BuiltinTypeSpec.Type.UShort:
4613 case BuiltinTypeSpec.Type.UInt:
4614 case BuiltinTypeSpec.Type.ULong:
4618 case BuiltinTypeSpec.Type.Short:
4619 switch (q.BuiltinType) {
4620 case BuiltinTypeSpec.Type.UShort:
4621 case BuiltinTypeSpec.Type.UInt:
4622 case BuiltinTypeSpec.Type.ULong:
4626 case BuiltinTypeSpec.Type.Dynamic:
4627 // LAMESPEC: Dynamic conversions is not considered
4628 p = ec.Module.Compiler.BuiltinTypes.Object;
4632 switch (q.BuiltinType) {
4633 case BuiltinTypeSpec.Type.Int:
4634 if (p.BuiltinType == BuiltinTypeSpec.Type.UInt || p.BuiltinType == BuiltinTypeSpec.Type.ULong)
4637 case BuiltinTypeSpec.Type.Long:
4638 if (p.BuiltinType == BuiltinTypeSpec.Type.ULong)
4641 case BuiltinTypeSpec.Type.SByte:
4642 switch (p.BuiltinType) {
4643 case BuiltinTypeSpec.Type.Byte:
4644 case BuiltinTypeSpec.Type.UShort:
4645 case BuiltinTypeSpec.Type.UInt:
4646 case BuiltinTypeSpec.Type.ULong:
4650 case BuiltinTypeSpec.Type.Short:
4651 switch (p.BuiltinType) {
4652 case BuiltinTypeSpec.Type.UShort:
4653 case BuiltinTypeSpec.Type.UInt:
4654 case BuiltinTypeSpec.Type.ULong:
4658 case BuiltinTypeSpec.Type.Dynamic:
4659 // LAMESPEC: Dynamic conversions is not considered
4660 q = ec.Module.Compiler.BuiltinTypes.Object;
4664 return BetterTypeConversionImplicitConversion (ec, p, q);
4667 static int BetterTypeConversionImplicitConversion (ResolveContext rc, TypeSpec p, TypeSpec q)
4669 // TODO: this is expensive
4670 Expression p_tmp = new EmptyExpression (p);
4671 Expression q_tmp = new EmptyExpression (q);
4673 bool p_to_q = Convert.ImplicitConversionExists (rc, p_tmp, q);
4674 bool q_to_p = Convert.ImplicitConversionExists (rc, q_tmp, p);
4676 if (p_to_q && !q_to_p)
4679 if (q_to_p && !p_to_q)
4686 /// Determines "Better function" between candidate
4687 /// and the current best match
4690 /// Returns a boolean indicating :
4691 /// false if candidate ain't better
4692 /// true if candidate is better than the current best match
4694 bool BetterFunction (ResolveContext ec, Arguments args, MemberSpec candidate, AParametersCollection cparam, bool candidate_params,
4695 MemberSpec best, AParametersCollection bparam, bool best_params)
4697 AParametersCollection candidate_pd = ((IParametersMember) candidate).Parameters;
4698 AParametersCollection best_pd = ((IParametersMember) best).Parameters;
4700 int candidate_better_count = 0;
4701 int best_better_count = 0;
4703 bool are_equivalent = true;
4704 int args_count = args == null ? 0 : args.Count;
4708 for (int c_idx = 0, b_idx = 0; j < args_count; ++j, ++c_idx, ++b_idx) {
4711 // Default arguments are ignored for better decision
4712 if (a.IsDefaultArgument)
4716 // When comparing named argument the parameter type index has to be looked up
4717 // in original parameter set (override version for virtual members)
4719 NamedArgument na = a as NamedArgument;
4721 int idx = cparam.GetParameterIndexByName (na.Name);
4722 ct = candidate_pd.Types[idx];
4723 if (candidate_params && candidate_pd.FixedParameters[idx].ModFlags == Parameter.Modifier.PARAMS)
4724 ct = TypeManager.GetElementType (ct);
4726 idx = bparam.GetParameterIndexByName (na.Name);
4727 bt = best_pd.Types[idx];
4728 if (best_params && best_pd.FixedParameters[idx].ModFlags == Parameter.Modifier.PARAMS)
4729 bt = TypeManager.GetElementType (bt);
4731 ct = candidate_pd.Types[c_idx];
4732 bt = best_pd.Types[b_idx];
4734 if (candidate_params && candidate_pd.FixedParameters[c_idx].ModFlags == Parameter.Modifier.PARAMS) {
4735 ct = TypeManager.GetElementType (ct);
4739 if (best_params && best_pd.FixedParameters[b_idx].ModFlags == Parameter.Modifier.PARAMS) {
4740 bt = TypeManager.GetElementType (bt);
4745 if (TypeSpecComparer.IsEqual (ct, bt))
4748 are_equivalent = false;
4749 int result = BetterExpressionConversion (ec, a, ct, bt);
4751 // for each argument, the conversion to 'ct' should be no worse than
4752 // the conversion to 'bt'.
4755 // No optional parameters tie breaking rules for delegates overload resolution
4757 if ((restrictions & Restrictions.CovariantDelegate) != 0)
4760 ++best_better_count;
4764 // for at least one argument, the conversion to 'ct' should be better than
4765 // the conversion to 'bt'.
4767 ++candidate_better_count;
4770 if (candidate_better_count != 0 && best_better_count == 0)
4773 if (best_better_count > 0 && candidate_better_count == 0)
4777 // LAMESPEC: Tie-breaking rules for not equivalent parameter types
4779 if (!are_equivalent) {
4780 while (j < args_count && !args [j++].IsDefaultArgument) ;
4783 // A candidate with no default parameters is still better when there
4784 // is no better expression conversion and does not have more parameters
4786 if (candidate_pd.Count < best_pd.Count) {
4787 if (candidate_params)
4790 if (!candidate_pd.FixedParameters [j - 1].HasDefaultValue)
4793 if (best_pd.FixedParameters [j].HasDefaultValue)
4796 } else if (candidate_pd.Count == best_pd.Count) {
4797 if (candidate_params)
4800 if (!candidate_pd.FixedParameters [j - 1].HasDefaultValue && best_pd.FixedParameters [j - 1].HasDefaultValue)
4803 if (candidate_pd.FixedParameters [j - 1].HasDefaultValue && best_pd.HasParams)
4811 // If candidate is applicable in its normal form and best has a params array and is applicable
4812 // only in its expanded form, then candidate is better
4814 if (candidate_params != best_params)
4815 return !candidate_params;
4818 // We have not reached end of parameters list due to params or used default parameters
4820 bool defaults_ambiguity = false;
4821 while (j < candidate_pd.Count && j < best_pd.Count) {
4822 var cand_param = candidate_pd.FixedParameters [j];
4823 var best_param = best_pd.FixedParameters [j];
4825 if (cand_param.HasDefaultValue != best_param.HasDefaultValue && (!candidate_pd.HasParams || !best_pd.HasParams))
4826 return cand_param.HasDefaultValue;
4828 defaults_ambiguity = true;
4829 if (candidate_pd.Count == best_pd.Count) {
4833 // void Foo (int i = 0) is better than void Foo (params int[]) for Foo ()
4834 // void Foo (string[] s, string value = null) is better than Foo (string s, params string[]) for Foo (null) or Foo ()
4836 if (cand_param.HasDefaultValue) {
4845 // Neither is better when not all arguments are provided
4847 // void Foo (string s, int i = 0) <-> Foo (string s, int i = 0, int i2 = 0)
4848 // void Foo (string s, int i = 0) <-> Foo (string s, byte i = 0)
4849 // void Foo (string s, params int[]) <-> Foo (string s, params byte[])
4854 if (candidate_pd.Count != best_pd.Count) {
4855 if (defaults_ambiguity && best_pd.Count - 1 == j)
4856 return best_pd.HasParams;
4858 return candidate_pd.Count < best_pd.Count;
4862 // One is a non-generic method and second is a generic method, then non-generic is better
4864 if (best.IsGeneric != candidate.IsGeneric)
4865 return best.IsGeneric;
4868 // Both methods have the same number of parameters, and the parameters have equal types
4869 // Pick the "more specific" signature using rules over original (non-inflated) types
4871 var candidate_def_pd = ((IParametersMember) candidate.MemberDefinition).Parameters;
4872 var best_def_pd = ((IParametersMember) best.MemberDefinition).Parameters;
4874 bool specific_at_least_once = false;
4875 for (j = 0; j < args_count; ++j) {
4876 NamedArgument na = args_count == 0 ? null : args [j] as NamedArgument;
4878 ct = candidate_def_pd.Types[cparam.GetParameterIndexByName (na.Name)];
4879 bt = best_def_pd.Types[bparam.GetParameterIndexByName (na.Name)];
4881 ct = candidate_def_pd.Types[j];
4882 bt = best_def_pd.Types[j];
4887 TypeSpec specific = MoreSpecific (ct, bt);
4891 specific_at_least_once = true;
4894 if (specific_at_least_once)
4900 static bool CheckInflatedArguments (MethodSpec ms)
4902 if (!TypeParameterSpec.HasAnyTypeParameterTypeConstrained (ms.GenericDefinition))
4905 // Setup constraint checker for probing only
4906 ConstraintChecker cc = new ConstraintChecker (null);
4908 var mp = ms.Parameters.Types;
4909 for (int i = 0; i < mp.Length; ++i) {
4910 var type = mp[i] as InflatedTypeSpec;
4914 var targs = type.TypeArguments;
4915 if (targs.Length == 0)
4918 // TODO: Checking inflated MVAR arguments should be enough
4919 if (!cc.CheckAll (type.GetDefinition (), targs, type.Constraints, Location.Null))
4926 public static void Error_ConstructorMismatch (ResolveContext rc, TypeSpec type, int argCount, Location loc)
4928 rc.Report.Error (1729, loc,
4929 "The type `{0}' does not contain a constructor that takes `{1}' arguments",
4930 type.GetSignatureForError (), argCount.ToString ());
4934 // Determines if the candidate method is applicable to the given set of arguments
4935 // There could be two different set of parameters for same candidate where one
4936 // is the closest override for default values and named arguments checks and second
4937 // one being the virtual base for the parameter types and modifiers.
4939 // A return value rates candidate method compatibility,
4941 // 0 = the best, int.MaxValue = the worst
4943 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)
4946 // Each step has allocated 10 values, it can overflow for
4947 // more than 10 arguments but that's ok as it's used for
4948 // better error reporting only
4950 const int ArgumentCountMismatch = 1000000000;
4951 const int NamedArgumentsMismatch = 100000000;
4952 const int DefaultArgumentMismatch = 10000000;
4953 const int UnexpectedTypeArguments = 1000000;
4954 const int TypeArgumentsMismatch = 100000;
4955 const int InflatedTypesMismatch = 10000;
4957 // Parameters of most-derived type used mainly for named and optional parameters
4958 var pd = pm.Parameters;
4960 // Used for params modifier only, that's legacy of C# 1.0 which uses base type for
4961 // params modifier instead of most-derived type
4962 var cpd = ((IParametersMember) candidate).Parameters;
4963 int param_count = pd.Count;
4964 int optional_count = 0;
4966 Arguments orig_args = arguments;
4968 if (arg_count != param_count) {
4970 // No arguments expansion when doing exact match for delegates
4972 if ((restrictions & Restrictions.CovariantDelegate) == 0) {
4973 for (int i = 0; i < pd.Count; ++i) {
4974 if (pd.FixedParameters[i].HasDefaultValue) {
4975 optional_count = pd.Count - i;
4981 if (optional_count != 0) {
4982 // Readjust expected number when params used
4983 if (cpd.HasParams) {
4985 if (arg_count < param_count)
4987 } else if (arg_count > param_count) {
4988 int args_gap = System.Math.Abs (arg_count - param_count);
4989 return ArgumentCountMismatch + args_gap;
4990 } else if (arg_count < param_count - optional_count) {
4991 int args_gap = System.Math.Abs (param_count - optional_count - arg_count);
4992 return ArgumentCountMismatch + args_gap;
4994 } else if (arg_count != param_count) {
4995 int args_gap = System.Math.Abs (arg_count - param_count);
4997 return ArgumentCountMismatch + args_gap;
4998 if (arg_count < param_count - 1)
4999 return ArgumentCountMismatch + args_gap;
5002 // Resize to fit optional arguments
5003 if (optional_count != 0) {
5004 if (arguments == null) {
5005 arguments = new Arguments (optional_count);
5007 // Have to create a new container, so the next run can do same
5008 var resized = new Arguments (param_count);
5009 resized.AddRange (arguments);
5010 arguments = resized;
5013 for (int i = arg_count; i < param_count; ++i)
5014 arguments.Add (null);
5018 if (arg_count > 0) {
5020 // Shuffle named arguments to the right positions if there are any
5022 if (arguments[arg_count - 1] is NamedArgument) {
5023 arg_count = arguments.Count;
5025 for (int i = 0; i < arg_count; ++i) {
5026 bool arg_moved = false;
5028 NamedArgument na = arguments[i] as NamedArgument;
5032 int index = pd.GetParameterIndexByName (na.Name);
5034 // Named parameter not found
5036 return NamedArgumentsMismatch - i;
5038 // already reordered
5043 if (index >= param_count) {
5044 // When using parameters which should not be available to the user
5045 if ((cpd.FixedParameters[index].ModFlags & Parameter.Modifier.PARAMS) == 0)
5048 arguments.Add (null);
5052 if (index == arg_count)
5053 return NamedArgumentsMismatch - i - 1;
5055 temp = arguments [index];
5057 // The slot has been taken by positional argument
5058 if (temp != null && !(temp is NamedArgument))
5059 return NamedArgumentsMismatch - i - 1;
5063 arguments = arguments.MarkOrderedArgument (na);
5067 if (arguments == orig_args) {
5068 arguments = new Arguments (orig_args.Count);
5069 arguments.AddRange (orig_args);
5072 arguments[index] = arguments[i];
5073 arguments[i] = temp;
5080 arg_count = arguments.Count;
5082 } else if (arguments != null) {
5083 arg_count = arguments.Count;
5087 // Don't do any expensive checks when the candidate cannot succeed
5089 if (arg_count != param_count && !cpd.HasParams)
5090 return DefaultArgumentMismatch - System.Math.Abs (param_count - arg_count);
5092 var dep = candidate.GetMissingDependencies ();
5094 ImportedTypeDefinition.Error_MissingDependency (ec, dep, loc);
5099 // 1. Handle generic method using type arguments when specified or type inference
5102 var ms = candidate as MethodSpec;
5103 if (ms != null && ms.IsGeneric) {
5104 if (type_arguments != null) {
5105 var g_args_count = ms.Arity;
5106 if (g_args_count != type_arguments.Count)
5107 return TypeArgumentsMismatch - System.Math.Abs (type_arguments.Count - g_args_count);
5109 if (type_arguments.Arguments != null)
5110 ms = ms.MakeGenericMethod (ec, type_arguments.Arguments);
5113 // Deploy custom error reporting for infered anonymous expression or lambda methods. When
5114 // probing lambda methods keep all errors reported in separate set and once we are done and no best
5115 // candidate was found use the set to report more details about what was wrong with lambda body.
5116 // The general idea is to distinguish between code errors and errors caused by
5117 // trial-and-error type inference
5119 if (lambda_conv_msgs == null) {
5120 for (int i = 0; i < arg_count; i++) {
5121 Argument a = arguments[i];
5125 var am = a.Expr as AnonymousMethodExpression;
5127 if (lambda_conv_msgs == null)
5128 lambda_conv_msgs = new SessionReportPrinter ();
5130 am.TypeInferenceReportPrinter = lambda_conv_msgs;
5135 var ti = new TypeInference (arguments);
5136 TypeSpec[] i_args = ti.InferMethodArguments (ec, ms);
5139 return TypeArgumentsMismatch - ti.InferenceScore;
5142 // Clear any error messages when the result was success
5144 if (lambda_conv_msgs != null)
5145 lambda_conv_msgs.ClearSession ();
5147 if (i_args.Length != 0) {
5149 for (int i = 0; i < i_args.Length; ++i) {
5150 var ta = i_args [i];
5151 if (!ta.IsAccessible (ec))
5152 return TypeArgumentsMismatch - i;
5156 ms = ms.MakeGenericMethod (ec, i_args);
5161 // Type arguments constraints have to match for the method to be applicable
5163 if (!CheckInflatedArguments (ms)) {
5165 return InflatedTypesMismatch;
5169 // We have a generic return type and at same time the method is override which
5170 // means we have to also inflate override return type in case the candidate is
5171 // best candidate and override return type is different to base return type.
5173 // virtual Foo<T, object> with override Foo<T, dynamic>
5175 if (candidate != pm) {
5176 MethodSpec override_ms = (MethodSpec) pm;
5177 var inflator = new TypeParameterInflator (ec, ms.DeclaringType, override_ms.GenericDefinition.TypeParameters, ms.TypeArguments);
5178 returnType = inflator.Inflate (returnType);
5180 returnType = ms.ReturnType;
5187 if (type_arguments != null)
5188 return UnexpectedTypeArguments;
5194 // 2. Each argument has to be implicitly convertible to method parameter
5196 Parameter.Modifier p_mod = 0;
5199 for (int i = 0; i < arg_count; i++) {
5200 Argument a = arguments[i];
5202 var fp = pd.FixedParameters[i];
5203 if (!fp.HasDefaultValue) {
5204 arguments = orig_args;
5205 return arg_count * 2 + 2;
5209 // Get the default value expression, we can use the same expression
5210 // if the type matches
5212 Expression e = fp.DefaultValue;
5214 e = ResolveDefaultValueArgument (ec, ptypes[i], e, loc);
5216 // Restore for possible error reporting
5217 for (int ii = i; ii < arg_count; ++ii)
5218 arguments.RemoveAt (i);
5220 return (arg_count - i) * 2 + 1;
5224 if ((fp.ModFlags & Parameter.Modifier.CallerMask) != 0) {
5226 // LAMESPEC: Attributes can be mixed together with build-in priority
5228 if ((fp.ModFlags & Parameter.Modifier.CallerLineNumber) != 0) {
5229 e = new IntLiteral (ec.BuiltinTypes, loc.Row, loc);
5230 } else if ((fp.ModFlags & Parameter.Modifier.CallerFilePath) != 0) {
5231 e = new StringLiteral (ec.BuiltinTypes, loc.SourceFile.GetFullPathName (ec.Module.Compiler.Settings.PathMap), loc);
5232 } else if (ec.MemberContext.CurrentMemberDefinition != null) {
5233 e = new StringLiteral (ec.BuiltinTypes, ec.MemberContext.CurrentMemberDefinition.GetCallerMemberName (), loc);
5237 arguments[i] = new Argument (e, Argument.AType.Default);
5241 if (p_mod != Parameter.Modifier.PARAMS) {
5242 p_mod = (pd.FixedParameters[i].ModFlags & ~Parameter.Modifier.PARAMS) | (cpd.FixedParameters[i].ModFlags & Parameter.Modifier.PARAMS);
5244 } else if (!params_expanded_form) {
5245 params_expanded_form = true;
5246 pt = ((ElementTypeSpec) pt).Element;
5252 if (!params_expanded_form) {
5253 if (a.IsExtensionType) {
5254 if (ExtensionMethodGroupExpr.IsExtensionTypeCompatible (a.Type, pt)) {
5259 score = IsArgumentCompatible (ec, a, p_mod, pt);
5262 dynamicArgument = true;
5267 // It can be applicable in expanded form (when not doing exact match like for delegates)
5269 if (score != 0 && (p_mod & Parameter.Modifier.PARAMS) != 0 && (restrictions & Restrictions.CovariantDelegate) == 0) {
5270 if (!params_expanded_form) {
5271 pt = ((ElementTypeSpec) pt).Element;
5275 score = IsArgumentCompatible (ec, a, Parameter.Modifier.NONE, pt);
5278 params_expanded_form = true;
5279 dynamicArgument = true;
5280 } else if (score == 0 || arg_count > pd.Count) {
5281 params_expanded_form = true;
5286 if (params_expanded_form)
5288 return (arg_count - i) * 2 + score;
5293 // Restore original arguments for dynamic binder to keep the intention of original source code
5295 if (dynamicArgument)
5296 arguments = orig_args;
5301 public static Expression ResolveDefaultValueArgument (ResolveContext ec, TypeSpec ptype, Expression e, Location loc)
5303 if (e is Constant && e.Type == ptype)
5307 // LAMESPEC: No idea what the exact rules are for System.Reflection.Missing.Value instead of null
5309 if (e == EmptyExpression.MissingValue && (ptype.BuiltinType == BuiltinTypeSpec.Type.Object || ptype.BuiltinType == BuiltinTypeSpec.Type.Dynamic)) {
5310 e = new MemberAccess (new MemberAccess (new MemberAccess (
5311 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "System", loc), "Reflection", loc), "Missing", loc), "Value", loc);
5312 } else if (e is Constant) {
5314 // Handles int to int? conversions, DefaultParameterValue check
5316 e = Convert.ImplicitConversionStandard (ec, e, ptype, loc);
5320 e = new DefaultValueExpression (new TypeExpression (ptype, loc), loc);
5323 return e.Resolve (ec);
5327 // Tests argument compatibility with the parameter
5328 // The possible return values are
5330 // 1 - modifier mismatch
5331 // 2 - type mismatch
5332 // -1 - dynamic binding required
5334 int IsArgumentCompatible (ResolveContext ec, Argument argument, Parameter.Modifier param_mod, TypeSpec parameter)
5337 // Types have to be identical when ref or out modifer
5338 // is used and argument is not of dynamic type
5340 if (((argument.Modifier | param_mod) & Parameter.Modifier.RefOutMask) != 0) {
5341 var arg_type = argument.Type;
5343 if ((argument.Modifier & Parameter.Modifier.RefOutMask) != (param_mod & Parameter.Modifier.RefOutMask)) {
5345 // Using dynamic for ref/out parameter can still succeed at runtime
5347 if (arg_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (argument.Modifier & Parameter.Modifier.RefOutMask) == 0 && (restrictions & Restrictions.CovariantDelegate) == 0)
5353 if (arg_type != parameter) {
5354 if (arg_type == InternalType.VarOutType)
5358 // Do full equality check after quick path
5360 if (!TypeSpecComparer.IsEqual (arg_type, parameter)) {
5362 // Using dynamic for ref/out parameter can still succeed at runtime
5364 if (arg_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (argument.Modifier & Parameter.Modifier.RefOutMask) == 0 && (restrictions & Restrictions.CovariantDelegate) == 0)
5372 if (argument.Type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (restrictions & Restrictions.CovariantDelegate) == 0)
5376 // Use implicit conversion in all modes to return same candidates when the expression
5377 // is used as argument or delegate conversion
5379 if (!Convert.ImplicitConversionExists (ec, argument.Expr, parameter)) {
5380 return parameter.IsDelegate && argument.Expr is AnonymousMethodExpression ? 2 : 3;
5387 static TypeSpec MoreSpecific (TypeSpec p, TypeSpec q)
5389 if (TypeManager.IsGenericParameter (p) && !TypeManager.IsGenericParameter (q))
5391 if (!TypeManager.IsGenericParameter (p) && TypeManager.IsGenericParameter (q))
5394 var ac_p = p as ArrayContainer;
5396 var ac_q = q as ArrayContainer;
5400 TypeSpec specific = MoreSpecific (ac_p.Element, ac_q.Element);
5401 if (specific == ac_p.Element)
5403 if (specific == ac_q.Element)
5405 } else if (p.IsGeneric && q.IsGeneric) {
5406 var pargs = TypeManager.GetTypeArguments (p);
5407 var qargs = TypeManager.GetTypeArguments (q);
5409 bool p_specific_at_least_once = false;
5410 bool q_specific_at_least_once = false;
5412 for (int i = 0; i < pargs.Length; i++) {
5413 TypeSpec specific = MoreSpecific (pargs[i], qargs[i]);
5414 if (specific == pargs[i])
5415 p_specific_at_least_once = true;
5416 if (specific == qargs[i])
5417 q_specific_at_least_once = true;
5420 if (p_specific_at_least_once && !q_specific_at_least_once)
5422 if (!p_specific_at_least_once && q_specific_at_least_once)
5430 // Find the best method from candidate list
5432 public T ResolveMember<T> (ResolveContext rc, ref Arguments args) where T : MemberSpec, IParametersMember
5434 List<AmbiguousCandidate> ambiguous_candidates = null;
5436 MemberSpec best_candidate;
5437 Arguments best_candidate_args = null;
5438 bool best_candidate_params = false;
5439 bool best_candidate_dynamic = false;
5440 int best_candidate_rate;
5441 IParametersMember best_parameter_member = null;
5443 int args_count = args != null ? args.Count : 0;
5445 Arguments candidate_args = args;
5446 bool error_mode = false;
5447 MemberSpec invocable_member = null;
5448 int applicable_candidates = 0;
5451 best_candidate = null;
5452 best_candidate_rate = int.MaxValue;
5454 var type_members = members;
5456 for (int i = 0; i < type_members.Count; ++i) {
5457 var member = type_members[i];
5460 // Methods in a base class are not candidates if any method in a derived
5461 // class is applicable
5463 if ((member.Modifiers & Modifiers.OVERRIDE) != 0)
5467 if (!member.IsAccessible (rc))
5470 if (rc.IsRuntimeBinder && !member.DeclaringType.IsAccessible (rc))
5473 if ((member.Modifiers & (Modifiers.PROTECTED | Modifiers.STATIC)) == Modifiers.PROTECTED &&
5474 instance_qualifier != null && !instance_qualifier.CheckProtectedMemberAccess (rc, member)) {
5479 IParametersMember pm = member as IParametersMember;
5482 // Will use it later to report ambiguity between best method and invocable member
5484 if (Invocation.IsMemberInvocable (member))
5485 invocable_member = member;
5491 // Overload resolution is looking for base member but using parameter names
5492 // and default values from the closest member. That means to do expensive lookup
5493 // for the closest override for virtual or abstract members
5495 if ((member.Modifiers & (Modifiers.VIRTUAL | Modifiers.ABSTRACT)) != 0) {
5496 var override_params = base_provider.GetOverrideMemberParameters (member);
5497 if (override_params != null)
5498 pm = override_params;
5502 // Check if the member candidate is applicable
5504 bool params_expanded_form = false;
5505 bool dynamic_argument = false;
5506 TypeSpec rt = pm.MemberType;
5507 int candidate_rate = IsApplicable (rc, ref candidate_args, args_count, ref member, pm, ref params_expanded_form, ref dynamic_argument, ref rt, error_mode);
5509 if (lambda_conv_msgs != null)
5510 lambda_conv_msgs.EndSession ();
5513 // How does it score compare to others
5515 if (candidate_rate < best_candidate_rate) {
5517 // Fatal error (missing dependency), cannot continue
5518 if (candidate_rate < 0)
5521 applicable_candidates = 1;
5522 if ((restrictions & Restrictions.GetEnumeratorLookup) != 0 && candidate_args.Count != 0) {
5523 // Only parameterless methods are considered
5525 best_candidate_rate = candidate_rate;
5526 best_candidate = member;
5527 best_candidate_args = candidate_args;
5528 best_candidate_params = params_expanded_form;
5529 best_candidate_dynamic = dynamic_argument;
5530 best_parameter_member = pm;
5531 best_candidate_return_type = rt;
5533 } else if (candidate_rate == 0) {
5535 // The member look is done per type for most operations but sometimes
5536 // it's not possible like for binary operators overload because they
5537 // are unioned between 2 sides
5539 if ((restrictions & Restrictions.BaseMembersIncluded) != 0) {
5540 if (TypeSpec.IsBaseClass (best_candidate.DeclaringType, member.DeclaringType, true))
5544 ++applicable_candidates;
5546 if (best_candidate.DeclaringType.IsInterface && member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
5548 // We pack all interface members into top level type which makes the overload resolution
5549 // more complicated for interfaces. We compensate it by removing methods with same
5550 // signature when building the cache hence this path should not really be hit often
5553 // interface IA { void Foo (int arg); }
5554 // interface IB : IA { void Foo (params int[] args); }
5556 // IB::Foo is the best overload when calling IB.Foo (1)
5559 if (ambiguous_candidates != null) {
5560 foreach (var amb_cand in ambiguous_candidates) {
5561 if (member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
5570 ambiguous_candidates = null;
5573 // Is the new candidate better
5574 is_better = BetterFunction (rc, candidate_args, member, pm.Parameters, params_expanded_form, best_candidate, best_parameter_member.Parameters, best_candidate_params);
5578 best_candidate = member;
5579 best_candidate_args = candidate_args;
5580 best_candidate_params = params_expanded_form;
5581 best_candidate_dynamic = dynamic_argument;
5582 best_parameter_member = pm;
5583 best_candidate_return_type = rt;
5585 // It's not better but any other found later could be but we are not sure yet
5586 if (ambiguous_candidates == null)
5587 ambiguous_candidates = new List<AmbiguousCandidate> ();
5589 ambiguous_candidates.Add (new AmbiguousCandidate (member, pm.Parameters, params_expanded_form));
5593 // Restore expanded arguments
5594 candidate_args = args;
5596 } while (best_candidate_rate != 0 && (type_members = base_provider.GetBaseMembers (type_members[0].DeclaringType)) != null);
5599 // We've found exact match
5601 if (best_candidate_rate == 0)
5605 // Try extension methods lookup when no ordinary method match was found and provider enables it
5608 var emg = base_provider.LookupExtensionMethod (rc);
5610 emg = emg.OverloadResolve (rc, ref args, null, restrictions);
5612 best_candidate_extension_group = emg;
5613 return (T) (MemberSpec) emg.BestCandidate;
5618 // Don't run expensive error reporting mode for probing
5625 if (lambda_conv_msgs != null && !lambda_conv_msgs.IsEmpty)
5628 lambda_conv_msgs = null;
5633 // No best member match found, report an error
5635 if (best_candidate_rate != 0 || error_mode) {
5636 ReportOverloadError (rc, best_candidate, best_parameter_member, best_candidate_args, best_candidate_params);
5640 if (best_candidate_dynamic) {
5641 if (args[0].IsExtensionType) {
5642 rc.Report.Error (1973, loc,
5643 "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",
5644 args [0].Type.GetSignatureForError (), best_candidate.Name, best_candidate.GetSignatureForError ());
5648 // Check type constraints only when explicit type arguments are used
5650 if (applicable_candidates == 1 && best_candidate.IsGeneric && type_arguments != null) {
5651 MethodSpec bc = best_candidate as MethodSpec;
5652 if (bc != null && TypeParameterSpec.HasAnyTypeParameterConstrained (bc.GenericDefinition)) {
5653 ConstraintChecker cc = new ConstraintChecker (rc);
5654 cc.CheckAll (bc.GetGenericMethodDefinition (), bc.TypeArguments, bc.Constraints, loc);
5658 BestCandidateIsDynamic = true;
5663 // These flags indicates we are running delegate probing conversion. No need to
5664 // do more expensive checks
5666 if ((restrictions & (Restrictions.ProbingOnly | Restrictions.CovariantDelegate)) == (Restrictions.CovariantDelegate | Restrictions.ProbingOnly))
5667 return (T) best_candidate;
5669 if (ambiguous_candidates != null) {
5671 // Now check that there are no ambiguities i.e the selected method
5672 // should be better than all the others
5674 for (int ix = 0; ix < ambiguous_candidates.Count; ix++) {
5675 var candidate = ambiguous_candidates [ix];
5677 if (!BetterFunction (rc, best_candidate_args, best_candidate, best_parameter_member.Parameters, best_candidate_params, candidate.Member, candidate.Parameters, candidate.Expanded)) {
5678 var ambiguous = candidate.Member;
5679 if (custom_errors == null || !custom_errors.AmbiguousCandidates (rc, best_candidate, ambiguous)) {
5680 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5681 rc.Report.SymbolRelatedToPreviousError (ambiguous);
5682 rc.Report.Error (121, loc, "The call is ambiguous between the following methods or properties: `{0}' and `{1}'",
5683 best_candidate.GetSignatureForError (), ambiguous.GetSignatureForError ());
5686 return (T) best_candidate;
5691 if (invocable_member != null && !IsProbingOnly) {
5692 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5693 rc.Report.SymbolRelatedToPreviousError (invocable_member);
5694 rc.Report.Warning (467, 2, loc, "Ambiguity between method `{0}' and invocable non-method `{1}'. Using method group",
5695 best_candidate.GetSignatureForError (), invocable_member.GetSignatureForError ());
5699 // And now check if the arguments are all
5700 // compatible, perform conversions if
5701 // necessary etc. and return if everything is
5704 if (!VerifyArguments (rc, ref best_candidate_args, best_candidate, best_parameter_member, best_candidate_params))
5707 if (best_candidate == null)
5711 // Don't run possibly expensive checks in probing mode
5713 if (!IsProbingOnly && !rc.IsInProbingMode) {
5715 // Check ObsoleteAttribute on the best method
5717 best_candidate.CheckObsoleteness (rc, loc);
5719 best_candidate.MemberDefinition.SetIsUsed ();
5722 args = best_candidate_args;
5723 return (T) best_candidate;
5726 public MethodSpec ResolveOperator (ResolveContext rc, ref Arguments args)
5728 return ResolveMember<MethodSpec> (rc, ref args);
5731 void ReportArgumentMismatch (ResolveContext ec, int idx, MemberSpec method,
5732 Argument a, AParametersCollection expected_par, TypeSpec paramType)
5734 if (custom_errors != null && custom_errors.ArgumentMismatch (ec, method, a, idx))
5737 if (a.Type == InternalType.ErrorType)
5740 if (a is CollectionElementInitializer.ElementInitializerArgument) {
5741 ec.Report.SymbolRelatedToPreviousError (method);
5742 if ((expected_par.FixedParameters[idx].ModFlags & Parameter.Modifier.RefOutMask) != 0) {
5743 ec.Report.Error (1954, loc, "The best overloaded collection initalizer method `{0}' cannot have `ref' or `out' modifier",
5744 TypeManager.CSharpSignature (method));
5747 ec.Report.Error (1950, loc, "The best overloaded collection initalizer method `{0}' has some invalid arguments",
5748 TypeManager.CSharpSignature (method));
5749 } else if (IsDelegateInvoke) {
5750 ec.Report.Error (1594, loc, "Delegate `{0}' has some invalid arguments",
5751 DelegateType.GetSignatureForError ());
5753 ec.Report.SymbolRelatedToPreviousError (method);
5754 ec.Report.Error (1502, loc, "The best overloaded method match for `{0}' has some invalid arguments",
5755 method.GetSignatureForError ());
5758 Parameter.Modifier mod = idx >= expected_par.Count ? 0 : expected_par.FixedParameters[idx].ModFlags;
5760 string index = (idx + 1).ToString ();
5761 if (((mod & Parameter.Modifier.RefOutMask) ^ (a.Modifier & Parameter.Modifier.RefOutMask)) != 0) {
5762 if ((mod & Parameter.Modifier.RefOutMask) == 0)
5763 ec.Report.Error (1615, a.Expr.Location, "Argument `#{0}' does not require `{1}' modifier. Consider removing `{1}' modifier",
5764 index, Parameter.GetModifierSignature (a.Modifier));
5766 ec.Report.Error (1620, a.Expr.Location, "Argument `#{0}' is missing `{1}' modifier",
5767 index, Parameter.GetModifierSignature (mod));
5769 string p1 = a.GetSignatureForError ();
5770 string p2 = paramType.GetSignatureForError ();
5773 p1 = a.Type.GetSignatureForErrorIncludingAssemblyName ();
5774 p2 = paramType.GetSignatureForErrorIncludingAssemblyName ();
5777 if ((mod & Parameter.Modifier.RefOutMask) != 0) {
5778 p1 = Parameter.GetModifierSignature (a.Modifier) + " " + p1;
5779 p2 = Parameter.GetModifierSignature (a.Modifier) + " " + p2;
5782 ec.Report.Error (1503, a.Expr.Location,
5783 "Argument `#{0}' cannot convert `{1}' expression to type `{2}'", index, p1, p2);
5788 // We have failed to find exact match so we return error info about the closest match
5790 void ReportOverloadError (ResolveContext rc, MemberSpec best_candidate, IParametersMember pm, Arguments args, bool params_expanded)
5792 int ta_count = type_arguments == null ? 0 : type_arguments.Count;
5793 int arg_count = args == null ? 0 : args.Count;
5795 if (ta_count != best_candidate.Arity && (ta_count > 0 || ((IParametersMember) best_candidate).Parameters.IsEmpty)) {
5796 var mg = new MethodGroupExpr (new [] { best_candidate }, best_candidate.DeclaringType, loc);
5797 mg.Error_TypeArgumentsCannotBeUsed (rc, best_candidate, loc);
5801 if (lambda_conv_msgs != null && lambda_conv_msgs.Merge (rc.Report.Printer)) {
5806 if ((best_candidate.Modifiers & (Modifiers.PROTECTED | Modifiers.STATIC)) == Modifiers.PROTECTED &&
5807 InstanceQualifier != null && !InstanceQualifier.CheckProtectedMemberAccess (rc, best_candidate)) {
5808 MemberExpr.Error_ProtectedMemberAccess (rc, best_candidate, InstanceQualifier.InstanceType, loc);
5812 // For candidates which match on parameters count report more details about incorrect arguments
5815 if (pm.Parameters.Count == arg_count || params_expanded || HasUnfilledParams (best_candidate, pm, args)) {
5816 // Reject any inaccessible member
5817 if (!best_candidate.IsAccessible (rc) || !best_candidate.DeclaringType.IsAccessible (rc)) {
5818 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5819 Expression.ErrorIsInaccesible (rc, best_candidate.GetSignatureForError (), loc);
5823 var ms = best_candidate as MethodSpec;
5824 if (ms != null && ms.IsGeneric) {
5825 bool constr_ok = true;
5826 if (ms.TypeArguments != null)
5827 constr_ok = new ConstraintChecker (rc.MemberContext).CheckAll (ms.GetGenericMethodDefinition (), ms.TypeArguments, ms.Constraints, loc);
5829 if (ta_count == 0 && ms.TypeArguments == null) {
5830 if (custom_errors != null && custom_errors.TypeInferenceFailed (rc, best_candidate))
5834 rc.Report.Error (411, loc,
5835 "The type arguments for method `{0}' cannot be inferred from the usage. Try specifying the type arguments explicitly",
5836 ms.GetGenericMethodDefinition ().GetSignatureForError ());
5843 VerifyArguments (rc, ref args, best_candidate, pm, params_expanded);
5849 // We failed to find any method with correct argument count, report best candidate
5851 if (custom_errors != null && custom_errors.NoArgumentMatch (rc, best_candidate))
5854 if (best_candidate.Kind == MemberKind.Constructor) {
5855 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5856 Error_ConstructorMismatch (rc, best_candidate.DeclaringType, arg_count, loc);
5857 } else if (IsDelegateInvoke) {
5858 rc.Report.SymbolRelatedToPreviousError (DelegateType);
5859 rc.Report.Error (1593, loc, "Delegate `{0}' does not take `{1}' arguments",
5860 DelegateType.GetSignatureForError (), arg_count.ToString ());
5862 string name = best_candidate.Kind == MemberKind.Indexer ? "this" : best_candidate.Name;
5863 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5864 rc.Report.Error (1501, loc, "No overload for method `{0}' takes `{1}' arguments",
5865 name, arg_count.ToString ());
5869 static bool HasUnfilledParams (MemberSpec best_candidate, IParametersMember pm, Arguments args)
5871 var p = ((IParametersMember)best_candidate).Parameters;
5876 for (int i = p.Count - 1; i != 0; --i) {
5877 var fp = p.FixedParameters [i];
5878 if ((fp.ModFlags & Parameter.Modifier.PARAMS) == 0)
5888 foreach (var arg in args) {
5889 var na = arg as NamedArgument;
5893 if (na.Name == name) {
5902 return args.Count + 1 == pm.Parameters.Count;
5905 bool VerifyArguments (ResolveContext ec, ref Arguments args, MemberSpec member, IParametersMember pm, bool chose_params_expanded)
5907 var pd = pm.Parameters;
5908 var cpd = ((IParametersMember) member).Parameters;
5909 var ptypes = cpd.Types;
5911 Parameter.Modifier p_mod = 0;
5913 int a_idx = 0, a_pos = 0;
5915 ArrayInitializer params_initializers = null;
5916 bool has_unsafe_arg = pm.MemberType.IsPointer;
5917 int arg_count = args == null ? 0 : args.Count;
5919 for (; a_idx < arg_count; a_idx++, ++a_pos) {
5924 if (p_mod != Parameter.Modifier.PARAMS) {
5925 p_mod = cpd.FixedParameters [a_idx].ModFlags;
5927 has_unsafe_arg |= pt.IsPointer;
5929 if (p_mod == Parameter.Modifier.PARAMS) {
5930 if (chose_params_expanded) {
5931 params_initializers = new ArrayInitializer (arg_count - a_idx, a.Expr.Location);
5932 pt = TypeManager.GetElementType (pt);
5938 // Types have to be identical when ref or out modifer is used
5940 if (((a.Modifier | p_mod) & Parameter.Modifier.RefOutMask) != 0) {
5941 if ((a.Modifier & Parameter.Modifier.RefOutMask) != (p_mod & Parameter.Modifier.RefOutMask))
5944 var arg_type = a.Type;
5948 if (arg_type == InternalType.VarOutType) {
5950 // Set underlying variable type based on parameter type
5952 ((DeclarationExpression)a.Expr).Variable.Type = pt;
5956 if (!TypeSpecComparer.IsEqual (arg_type, pt))
5960 NamedArgument na = a as NamedArgument;
5962 int name_index = pd.GetParameterIndexByName (na.Name);
5963 if (name_index < 0 || name_index >= pd.Count) {
5964 if (IsDelegateInvoke) {
5965 ec.Report.SymbolRelatedToPreviousError (DelegateType);
5966 ec.Report.Error (1746, na.Location,
5967 "The delegate `{0}' does not contain a parameter named `{1}'",
5968 DelegateType.GetSignatureForError (), na.Name);
5970 ec.Report.SymbolRelatedToPreviousError (member);
5971 ec.Report.Error (1739, na.Location,
5972 "The best overloaded method match for `{0}' does not contain a parameter named `{1}'",
5973 TypeManager.CSharpSignature (member), na.Name);
5975 } else if (args[name_index] != a && args[name_index] != null) {
5976 if (IsDelegateInvoke)
5977 ec.Report.SymbolRelatedToPreviousError (DelegateType);
5979 ec.Report.SymbolRelatedToPreviousError (member);
5981 ec.Report.Error (1744, na.Location,
5982 "Named argument `{0}' cannot be used for a parameter which has positional argument specified",
5987 if (a.Expr.Type.BuiltinType == BuiltinTypeSpec.Type.Dynamic)
5990 if ((restrictions & Restrictions.CovariantDelegate) != 0 && !Delegate.IsTypeCovariant (ec, a.Expr.Type, pt)) {
5991 if (a.IsExtensionType) {
5992 // TODO: Should report better message type, something similar to CS1928/1929 instead of
5993 // CS1061 but that still better than confusing CS0123
5994 var ma = new MemberAccess (a.Expr, member.Name, loc);
5995 ma.Error_TypeDoesNotContainDefinition (ec, a.Expr.Type, ma.Name);
5997 custom_errors.NoArgumentMatch (ec, member);
6003 if (a.IsExtensionType) {
6004 if (a.Expr.Type == pt || TypeSpecComparer.IsEqual (a.Expr.Type, pt)) {
6007 conv = Convert.ImplicitReferenceConversion (a.Expr, pt, false);
6009 conv = Convert.ImplicitBoxingConversion (a.Expr, a.Expr.Type, pt);
6012 conv = Convert.ImplicitConversion (ec, a.Expr, pt, loc);
6019 // Convert params arguments to an array initializer
6021 if (params_initializers != null) {
6022 // we choose to use 'a.Expr' rather than 'conv' so that
6023 // we don't hide the kind of expression we have (esp. CompoundAssign.Helper)
6024 params_initializers.Add (a.Expr);
6025 args.RemoveAt (a_idx--);
6031 // Update the argument with the implicit conversion
6035 if (a_idx != arg_count) {
6037 // Convert all var out argument to error type for less confusing error reporting
6038 // when no matching overload is found
6040 for (; a_idx < arg_count; a_idx++) {
6041 var arg = args [a_idx];
6045 if (arg.Type == InternalType.VarOutType) {
6046 ((DeclarationExpression)arg.Expr).Variable.Type = InternalType.ErrorType;
6050 ReportArgumentMismatch (ec, a_pos, member, a, pd, pt);
6055 // Fill not provided arguments required by params modifier
6057 if (params_initializers == null && arg_count + 1 == pd.Count) {
6059 args = new Arguments (1);
6061 pt = ptypes[pd.Count - 1];
6062 pt = TypeManager.GetElementType (pt);
6063 has_unsafe_arg |= pt.IsPointer;
6064 params_initializers = new ArrayInitializer (0, loc);
6068 // Append an array argument with all params arguments
6070 if (params_initializers != null) {
6071 args.Add (new Argument (
6072 new ArrayCreation (new TypeExpression (pt, loc), params_initializers, loc).Resolve (ec)));
6076 if (has_unsafe_arg && !ec.IsUnsafe) {
6077 Expression.UnsafeError (ec, loc);
6081 // We could infer inaccesible type arguments
6083 if (type_arguments == null && member.IsGeneric) {
6084 var ms = (MethodSpec) member;
6085 foreach (var ta in ms.TypeArguments) {
6086 if (!ta.IsAccessible (ec)) {
6087 ec.Report.SymbolRelatedToPreviousError (ta);
6088 Expression.ErrorIsInaccesible (ec, member.GetSignatureForError (), loc);
6098 public class ConstantExpr : MemberExpr
6100 readonly ConstSpec constant;
6102 public ConstantExpr (ConstSpec constant, Location loc)
6104 this.constant = constant;
6108 public override string Name {
6109 get { throw new NotImplementedException (); }
6112 public override string KindName {
6113 get { return "constant"; }
6116 public override bool IsInstance {
6117 get { return !IsStatic; }
6120 public override bool IsStatic {
6121 get { return true; }
6124 protected override TypeSpec DeclaringType {
6125 get { return constant.DeclaringType; }
6128 public override Expression CreateExpressionTree (ResolveContext ec)
6130 throw new NotSupportedException ("ET");
6133 protected override Expression DoResolve (ResolveContext rc)
6135 ResolveInstanceExpression (rc, null);
6136 DoBestMemberChecks (rc, constant);
6138 if (rc.HasSet (ResolveContext.Options.NameOfScope)) {
6139 eclass = ExprClass.Value;
6140 type = constant.MemberType;
6144 var c = constant.GetConstant (rc);
6146 // Creates reference expression to the constant value
6147 return Constant.CreateConstantFromValue (constant.MemberType, c.GetValue (), loc);
6150 public override void Emit (EmitContext ec)
6152 throw new NotSupportedException ();
6155 public override string GetSignatureForError ()
6157 return constant.GetSignatureForError ();
6160 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
6162 constant.CheckObsoleteness (rc, expr.Location);
6165 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
6167 Error_TypeArgumentsCannotBeUsed (ec, "constant", GetSignatureForError (), loc);
6172 // Fully resolved expression that references a Field
6174 public class FieldExpr : MemberExpr, IDynamicAssign, IMemoryLocation, IVariableReference
6176 protected FieldSpec spec;
6177 VariableInfo variable_info;
6179 LocalTemporary temp;
6182 protected FieldExpr (Location l)
6187 public FieldExpr (FieldSpec spec, Location loc)
6192 type = spec.MemberType;
6195 public FieldExpr (FieldBase fi, Location l)
6202 public override string Name {
6208 public bool IsHoisted {
6210 IVariableReference hv = InstanceExpression as IVariableReference;
6211 return hv != null && hv.IsHoisted;
6215 public override bool IsInstance {
6217 return !spec.IsStatic;
6221 public override bool IsStatic {
6223 return spec.IsStatic;
6227 public override string KindName {
6228 get { return "field"; }
6231 public FieldSpec Spec {
6237 protected override TypeSpec DeclaringType {
6239 return spec.DeclaringType;
6243 public VariableInfo VariableInfo {
6245 return variable_info;
6251 public override string GetSignatureForError ()
6253 return spec.GetSignatureForError ();
6256 public bool IsMarshalByRefAccess (ResolveContext rc)
6258 // Checks possible ldflda of field access expression
6259 return !spec.IsStatic && TypeSpec.IsValueType (spec.MemberType) && !(InstanceExpression is This) &&
6260 rc.Module.PredefinedTypes.MarshalByRefObject.Define () &&
6261 TypeSpec.IsBaseClass (spec.DeclaringType, rc.Module.PredefinedTypes.MarshalByRefObject.TypeSpec, false);
6264 public void SetHasAddressTaken ()
6266 IVariableReference vr = InstanceExpression as IVariableReference;
6268 vr.SetHasAddressTaken ();
6272 protected override void CloneTo (CloneContext clonectx, Expression target)
6274 var t = (FieldExpr) target;
6276 if (InstanceExpression != null)
6277 t.InstanceExpression = InstanceExpression.Clone (clonectx);
6280 public override Expression CreateExpressionTree (ResolveContext ec)
6282 if (ConditionalAccess) {
6283 Error_NullShortCircuitInsideExpressionTree (ec);
6286 return CreateExpressionTree (ec, true);
6289 public Expression CreateExpressionTree (ResolveContext ec, bool convertInstance)
6292 Expression instance;
6294 if (InstanceExpression == null) {
6295 instance = new NullLiteral (loc);
6296 } else if (convertInstance) {
6297 instance = InstanceExpression.CreateExpressionTree (ec);
6299 args = new Arguments (1);
6300 args.Add (new Argument (InstanceExpression));
6301 instance = CreateExpressionFactoryCall (ec, "Constant", args);
6304 args = Arguments.CreateForExpressionTree (ec, null,
6306 CreateTypeOfExpression ());
6308 return CreateExpressionFactoryCall (ec, "Field", args);
6311 public Expression CreateTypeOfExpression ()
6313 return new TypeOfField (spec, loc);
6316 protected override Expression DoResolve (ResolveContext ec)
6318 spec.MemberDefinition.SetIsUsed ();
6320 return DoResolve (ec, null);
6323 Expression DoResolve (ResolveContext ec, Expression rhs)
6325 bool lvalue_instance = rhs != null && IsInstance && spec.DeclaringType.IsStruct;
6328 ResolveConditionalAccessReceiver (ec);
6330 if (ResolveInstanceExpression (ec, rhs)) {
6331 // Resolve the field's instance expression while flow analysis is turned
6332 // off: when accessing a field "a.b", we must check whether the field
6333 // "a.b" is initialized, not whether the whole struct "a" is initialized.
6335 if (lvalue_instance) {
6336 bool out_access = rhs == EmptyExpression.OutAccess || rhs == EmptyExpression.LValueMemberOutAccess;
6338 Expression right_side =
6339 out_access ? EmptyExpression.LValueMemberOutAccess : EmptyExpression.LValueMemberAccess;
6341 InstanceExpression = InstanceExpression.ResolveLValue (ec, right_side);
6343 InstanceExpression = InstanceExpression.Resolve (ec, ResolveFlags.VariableOrValue);
6346 if (InstanceExpression == null)
6350 DoBestMemberChecks (ec, spec);
6352 if (conditional_access_receiver)
6353 ec.With (ResolveContext.Options.DontSetConditionalAccessReceiver, false);
6356 var fb = spec as FixedFieldSpec;
6357 IVariableReference var = InstanceExpression as IVariableReference;
6360 IFixedExpression fe = InstanceExpression as IFixedExpression;
6361 if (!ec.HasSet (ResolveContext.Options.FixedInitializerScope) && (fe == null || !fe.IsFixed)) {
6362 ec.Report.Error (1666, loc, "You cannot use fixed size buffers contained in unfixed expressions. Try using the fixed statement");
6365 if (InstanceExpression.eclass != ExprClass.Variable) {
6366 ec.Report.SymbolRelatedToPreviousError (spec);
6367 ec.Report.Error (1708, loc, "`{0}': Fixed size buffers can only be accessed through locals or fields",
6368 TypeManager.GetFullNameSignature (spec));
6369 } else if (var != null && var.IsHoisted) {
6370 AnonymousMethodExpression.Error_AddressOfCapturedVar (ec, var, loc);
6373 return new FixedBufferPtr (this, fb.ElementType, loc).Resolve (ec);
6377 // Set flow-analysis variable info for struct member access. It will be check later
6378 // for precise error reporting
6380 if (var != null && var.VariableInfo != null && InstanceExpression.Type.IsStruct) {
6381 variable_info = var.VariableInfo.GetStructFieldInfo (Name);
6384 if (conditional_access_receiver)
6385 type = LiftMemberType (ec, type);
6387 if (ConditionalAccess && InstanceExpression != null && InstanceExpression.IsNull)
6388 return Constant.CreateConstantFromValue (type, null, loc);
6390 eclass = ExprClass.Variable;
6394 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
6396 spec.CheckObsoleteness (rc, expr.Location);
6399 public void SetFieldAssigned (FlowAnalysisContext fc)
6404 bool lvalue_instance = spec.DeclaringType.IsStruct;
6405 if (lvalue_instance) {
6406 var var = InstanceExpression as IVariableReference;
6407 if (var != null && var.VariableInfo != null) {
6408 fc.SetStructFieldAssigned (var.VariableInfo, Name);
6412 var fe = InstanceExpression as FieldExpr;
6414 Expression instance;
6417 instance = fe.InstanceExpression;
6418 var fe_instance = instance as FieldExpr;
6419 if ((fe_instance != null && !fe_instance.IsStatic) || instance is LocalVariableReference) {
6420 if (TypeSpec.IsReferenceType (fe.Type) && instance.Type.IsStruct) {
6421 var var = InstanceExpression as IVariableReference;
6422 if (var != null && var.VariableInfo == null) {
6423 var var_inst = instance as IVariableReference;
6424 if (var_inst == null || (var_inst.VariableInfo != null && !fc.IsDefinitelyAssigned (var_inst.VariableInfo)))
6425 fc.Report.Warning (1060, 1, fe.loc, "Use of possibly unassigned field `{0}'", fe.Name);
6429 if (fe_instance != null) {
6438 if (instance != null && TypeSpec.IsReferenceType (instance.Type))
6439 instance.FlowAnalysis (fc);
6441 if (TypeSpec.IsReferenceType (InstanceExpression.Type))
6442 InstanceExpression.FlowAnalysis (fc);
6446 Expression Error_AssignToReadonly (ResolveContext rc, Expression right_side)
6448 // The return value is always null. Returning a value simplifies calling code.
6450 if (right_side == EmptyExpression.OutAccess) {
6452 rc.Report.Error (199, loc, "A static readonly field `{0}' cannot be passed ref or out (except in a static constructor)",
6453 GetSignatureForError ());
6455 rc.Report.Error (192, loc, "A readonly field `{0}' cannot be passed ref or out (except in a constructor)",
6456 GetSignatureForError ());
6462 if (right_side == EmptyExpression.LValueMemberAccess) {
6463 // Already reported as CS1648/CS1650
6467 if (right_side == EmptyExpression.LValueMemberOutAccess) {
6469 rc.Report.Error (1651, loc, "Fields of static readonly field `{0}' cannot be passed ref or out (except in a static constructor)",
6470 GetSignatureForError ());
6472 rc.Report.Error (1649, loc, "Members of readonly field `{0}' cannot be passed ref or out (except in a constructor)",
6473 GetSignatureForError ());
6479 rc.Report.Error (198, loc, "A static readonly field `{0}' cannot be assigned to (except in a static constructor or a variable initializer)",
6480 GetSignatureForError ());
6482 rc.Report.Error (191, loc, "A readonly field `{0}' cannot be assigned to (except in a constructor or a variable initializer)",
6483 GetSignatureForError ());
6489 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
6491 if (HasConditionalAccess ())
6492 Error_NullPropagatingLValue (ec);
6494 if (spec is FixedFieldSpec) {
6495 // It could be much better error message but we want to be error compatible
6496 Error_ValueAssignment (ec, right_side);
6499 Expression e = DoResolve (ec, right_side);
6504 spec.MemberDefinition.SetIsAssigned ();
6506 if ((right_side == EmptyExpression.UnaryAddress || right_side == EmptyExpression.OutAccess) &&
6507 (spec.Modifiers & Modifiers.VOLATILE) != 0) {
6508 ec.Report.Warning (420, 1, loc,
6509 "`{0}': A volatile field references will not be treated as volatile",
6510 spec.GetSignatureForError ());
6513 if (spec.IsReadOnly) {
6514 // InitOnly fields can only be assigned in constructors or initializers
6515 if (!ec.HasAny (ResolveContext.Options.FieldInitializerScope | ResolveContext.Options.ConstructorScope))
6516 return Error_AssignToReadonly (ec, right_side);
6518 if (ec.HasSet (ResolveContext.Options.ConstructorScope)) {
6520 // InitOnly fields cannot be assigned-to in a different constructor from their declaring type
6521 if (ec.CurrentMemberDefinition.Parent.PartialContainer.Definition != spec.DeclaringType.GetDefinition ())
6522 return Error_AssignToReadonly (ec, right_side);
6523 // static InitOnly fields cannot be assigned-to in an instance constructor
6524 if (IsStatic && !ec.IsStatic)
6525 return Error_AssignToReadonly (ec, right_side);
6526 // instance constructors can't modify InitOnly fields of other instances of the same type
6527 if (!IsStatic && !(InstanceExpression is This))
6528 return Error_AssignToReadonly (ec, right_side);
6532 if (right_side == EmptyExpression.OutAccess && IsMarshalByRefAccess (ec)) {
6533 ec.Report.SymbolRelatedToPreviousError (spec.DeclaringType);
6534 ec.Report.Warning (197, 1, loc,
6535 "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",
6536 GetSignatureForError ());
6539 eclass = ExprClass.Variable;
6543 public override void FlowAnalysis (FlowAnalysisContext fc)
6545 var var = InstanceExpression as IVariableReference;
6547 var vi = var.VariableInfo;
6548 if (vi != null && !fc.IsStructFieldDefinitelyAssigned (vi, Name)) {
6549 fc.Report.Error (170, loc, "Use of possibly unassigned field `{0}'", Name);
6553 if (TypeSpec.IsValueType (InstanceExpression.Type)) {
6554 var le = SkipLeftValueTypeAccess (InstanceExpression);
6556 le.FlowAnalysis (fc);
6562 var da = conditional_access_receiver ? fc.BranchDefiniteAssignment () : null;
6564 base.FlowAnalysis (fc);
6566 if (conditional_access_receiver)
6567 fc.DefiniteAssignment = da;
6570 static Expression SkipLeftValueTypeAccess (Expression expr)
6572 if (!TypeSpec.IsValueType (expr.Type))
6575 if (expr is VariableReference)
6578 var fe = expr as FieldExpr;
6582 if (fe.InstanceExpression == null)
6585 return SkipLeftValueTypeAccess (fe.InstanceExpression);
6588 public override int GetHashCode ()
6590 return spec.GetHashCode ();
6593 public bool IsFixed {
6596 // A variable of the form V.I is fixed when V is a fixed variable of a struct type
6598 IVariableReference variable = InstanceExpression as IVariableReference;
6599 if (variable != null)
6600 return InstanceExpression.Type.IsStruct && variable.IsFixed;
6602 IFixedExpression fe = InstanceExpression as IFixedExpression;
6603 return fe != null && fe.IsFixed;
6607 public override bool Equals (object obj)
6609 FieldExpr fe = obj as FieldExpr;
6613 if (spec != fe.spec)
6616 if (InstanceExpression == null || fe.InstanceExpression == null)
6619 return InstanceExpression.Equals (fe.InstanceExpression);
6622 public void Emit (EmitContext ec, bool leave_copy)
6624 bool is_volatile = (spec.Modifiers & Modifiers.VOLATILE) != 0;
6628 ec.Emit (OpCodes.Volatile);
6630 ec.Emit (OpCodes.Ldsfld, spec);
6632 var ca = ec.ConditionalAccess;
6635 if (conditional_access_receiver)
6636 ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
6638 EmitInstance (ec, false);
6641 // Optimization for build-in types
6642 if (type.IsStruct && type == ec.CurrentType && InstanceExpression.Type == type) {
6643 ec.EmitLoadFromPtr (type);
6645 var ff = spec as FixedFieldSpec;
6647 ec.Emit (OpCodes.Ldflda, spec);
6648 ec.Emit (OpCodes.Ldflda, ff.Element);
6651 ec.Emit (OpCodes.Volatile);
6653 ec.Emit (OpCodes.Ldfld, spec);
6657 if (conditional_access_receiver) {
6658 ec.CloseConditionalAccess (type.IsNullableType && type != spec.MemberType ? type : null);
6659 ec.ConditionalAccess = ca;
6664 ec.Emit (OpCodes.Dup);
6666 temp = new LocalTemporary (this.Type);
6672 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
6674 bool has_await_source = ec.HasSet (BuilderContext.Options.AsyncBody) && source.ContainsEmitWithAwait ();
6675 if (isCompound && !(source is DynamicExpressionStatement) && !has_await_source) {
6680 if (ConditionalAccess)
6681 throw new NotImplementedException ("null operator assignment");
6683 if (has_await_source)
6684 source = source.EmitToField (ec);
6686 EmitInstance (ec, prepared);
6691 if (leave_copy || ec.NotifyEvaluatorOnStore) {
6692 ec.Emit (OpCodes.Dup);
6694 temp = new LocalTemporary (this.Type);
6699 if ((spec.Modifiers & Modifiers.VOLATILE) != 0)
6700 ec.Emit (OpCodes.Volatile);
6702 spec.MemberDefinition.SetIsAssigned ();
6705 ec.Emit (OpCodes.Stsfld, spec);
6707 ec.Emit (OpCodes.Stfld, spec);
6709 if (ec.NotifyEvaluatorOnStore) {
6711 throw new NotImplementedException ("instance field write");
6714 ec.Emit (OpCodes.Dup);
6716 ec.Module.Evaluator.EmitValueChangedCallback (ec, Name, type, loc);
6727 // Emits store to field with prepared values on stack
6729 public void EmitAssignFromStack (EmitContext ec)
6732 ec.Emit (OpCodes.Stsfld, spec);
6734 ec.Emit (OpCodes.Stfld, spec);
6738 public override void Emit (EmitContext ec)
6743 public override void EmitSideEffect (EmitContext ec)
6745 bool is_volatile = (spec.Modifiers & Modifiers.VOLATILE) != 0;
6747 if (is_volatile) // || is_marshal_by_ref ())
6748 base.EmitSideEffect (ec);
6751 public virtual void AddressOf (EmitContext ec, AddressOp mode)
6753 if ((mode & AddressOp.Store) != 0)
6754 spec.MemberDefinition.SetIsAssigned ();
6755 if ((mode & AddressOp.Load) != 0)
6756 spec.MemberDefinition.SetIsUsed ();
6759 // Handle initonly fields specially: make a copy and then
6760 // get the address of the copy.
6763 if (spec.IsReadOnly){
6765 if (ec.HasSet (EmitContext.Options.ConstructorScope) && spec.DeclaringType == ec.CurrentType) {
6777 var temp = ec.GetTemporaryLocal (type);
6778 ec.Emit (OpCodes.Stloc, temp);
6779 ec.Emit (OpCodes.Ldloca, temp);
6785 ec.Emit (OpCodes.Ldsflda, spec);
6788 EmitInstance (ec, false);
6789 ec.Emit (OpCodes.Ldflda, spec);
6793 public SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source)
6795 return MakeExpression (ctx);
6798 public override SLE.Expression MakeExpression (BuilderContext ctx)
6801 return base.MakeExpression (ctx);
6803 return SLE.Expression.Field (
6804 IsStatic ? null : InstanceExpression.MakeExpression (ctx),
6805 spec.GetMetaInfo ());
6809 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
6811 Error_TypeArgumentsCannotBeUsed (ec, "field", GetSignatureForError (), loc);
6817 // Expression that evaluates to a Property.
6819 // This is not an LValue because we need to re-write the expression. We
6820 // can not take data from the stack and store it.
6822 sealed class PropertyExpr : PropertyOrIndexerExpr<PropertySpec>
6824 Arguments arguments;
6825 FieldExpr backing_field;
6827 public PropertyExpr (PropertySpec spec, Location l)
6830 best_candidate = spec;
6831 type = spec.MemberType;
6836 protected override Arguments Arguments {
6845 protected override TypeSpec DeclaringType {
6847 return best_candidate.DeclaringType;
6851 public override string Name {
6853 return best_candidate.Name;
6857 public bool IsAutoPropertyAccess {
6859 var prop = best_candidate.MemberDefinition as Property;
6860 return prop != null && prop.BackingField != null;
6864 public override bool IsInstance {
6870 public override bool IsStatic {
6872 return best_candidate.IsStatic;
6876 public override string KindName {
6877 get { return "property"; }
6880 public PropertySpec PropertyInfo {
6882 return best_candidate;
6888 public override MethodGroupExpr CanReduceLambda (AnonymousMethodBody body)
6890 if (best_candidate == null || !(best_candidate.IsStatic || InstanceExpression is This))
6893 var args_count = arguments == null ? 0 : arguments.Count;
6894 if (args_count != body.Parameters.Count && args_count == 0)
6897 var mg = MethodGroupExpr.CreatePredefined (best_candidate.Get, DeclaringType, loc);
6898 mg.InstanceExpression = InstanceExpression;
6903 public static PropertyExpr CreatePredefined (PropertySpec spec, Location loc)
6905 return new PropertyExpr (spec, loc) {
6911 public override Expression CreateExpressionTree (ResolveContext ec)
6913 if (ConditionalAccess) {
6914 Error_NullShortCircuitInsideExpressionTree (ec);
6918 if (IsSingleDimensionalArrayLength ()) {
6919 args = new Arguments (1);
6920 args.Add (new Argument (InstanceExpression.CreateExpressionTree (ec)));
6921 return CreateExpressionFactoryCall (ec, "ArrayLength", args);
6924 args = new Arguments (2);
6925 if (InstanceExpression == null)
6926 args.Add (new Argument (new NullLiteral (loc)));
6928 args.Add (new Argument (InstanceExpression.CreateExpressionTree (ec)));
6929 args.Add (new Argument (new TypeOfMethod (Getter, loc)));
6930 return CreateExpressionFactoryCall (ec, "Property", args);
6933 public Expression CreateSetterTypeOfExpression (ResolveContext rc)
6935 DoResolveLValue (rc, null);
6936 return new TypeOfMethod (Setter, loc);
6939 public override string GetSignatureForError ()
6941 return best_candidate.GetSignatureForError ();
6944 public override SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source)
6947 return base.MakeExpression (ctx);
6949 return SLE.Expression.Property (InstanceExpression.MakeExpression (ctx), (MethodInfo) Setter.GetMetaInfo ());
6953 public override SLE.Expression MakeExpression (BuilderContext ctx)
6956 return base.MakeExpression (ctx);
6958 return SLE.Expression.Property (InstanceExpression.MakeExpression (ctx), (MethodInfo) Getter.GetMetaInfo ());
6962 void Error_PropertyNotValid (ResolveContext ec)
6964 ec.Report.SymbolRelatedToPreviousError (best_candidate);
6965 ec.Report.Error (1546, loc, "Property or event `{0}' is not supported by the C# language",
6966 GetSignatureForError ());
6969 bool IsSingleDimensionalArrayLength ()
6971 if (best_candidate.DeclaringType.BuiltinType != BuiltinTypeSpec.Type.Array || !best_candidate.HasGet || Name != "Length")
6974 ArrayContainer ac = InstanceExpression.Type as ArrayContainer;
6975 return ac != null && ac.Rank == 1;
6978 public override void Emit (EmitContext ec, bool leave_copy)
6981 // Special case: length of single dimension array property is turned into ldlen
6983 if (IsSingleDimensionalArrayLength ()) {
6984 if (conditional_access_receiver) {
6985 ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
6988 EmitInstance (ec, false);
6990 ec.Emit (OpCodes.Ldlen);
6991 ec.Emit (OpCodes.Conv_I4);
6993 if (conditional_access_receiver) {
6994 ec.CloseConditionalAccess (type);
7000 base.Emit (ec, leave_copy);
7003 public override void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
7005 if (backing_field != null) {
7006 backing_field.EmitAssign (ec, source, false, false);
7011 LocalTemporary await_source_arg = null;
7013 if (isCompound && !(source is DynamicExpressionStatement)) {
7014 emitting_compound_assignment = true;
7017 if (has_await_arguments) {
7018 await_source_arg = new LocalTemporary (Type);
7019 await_source_arg.Store (ec);
7021 args = new Arguments (1);
7022 args.Add (new Argument (await_source_arg));
7025 temp = await_source_arg;
7028 has_await_arguments = false;
7033 ec.Emit (OpCodes.Dup);
7034 temp = new LocalTemporary (this.Type);
7039 args = arguments ?? new Arguments (1);
7043 temp = new LocalTemporary (this.Type);
7045 args.Add (new Argument (temp));
7047 args.Add (new Argument (source));
7051 emitting_compound_assignment = false;
7053 var call = new CallEmitter ();
7054 call.InstanceExpression = InstanceExpression;
7056 call.InstanceExpressionOnStack = true;
7058 if (ConditionalAccess) {
7059 call.ConditionalAccess = true;
7063 call.Emit (ec, Setter, args, loc);
7065 call.EmitStatement (ec, Setter, args, loc);
7072 if (await_source_arg != null) {
7073 await_source_arg.Release (ec);
7077 public override void FlowAnalysis (FlowAnalysisContext fc)
7079 var prop = best_candidate.MemberDefinition as Property;
7080 if (prop != null && prop.BackingField != null) {
7081 var var = InstanceExpression as IVariableReference;
7083 var vi = var.VariableInfo;
7084 if (vi != null && !fc.IsStructFieldDefinitelyAssigned (vi, prop.BackingField.Name)) {
7085 fc.Report.Error (8079, loc, "Use of possibly unassigned auto-implemented property `{0}'", Name);
7089 if (TypeSpec.IsValueType (InstanceExpression.Type) && InstanceExpression is VariableReference)
7094 var da = conditional_access_receiver ? fc.BranchDefiniteAssignment () : null;
7096 base.FlowAnalysis (fc);
7098 if (conditional_access_receiver)
7099 fc.DefiniteAssignment = da;
7102 protected override Expression OverloadResolve (ResolveContext rc, Expression right_side)
7104 eclass = ExprClass.PropertyAccess;
7106 if (best_candidate.IsNotCSharpCompatible) {
7107 Error_PropertyNotValid (rc);
7110 ResolveInstanceExpression (rc, right_side);
7112 if ((best_candidate.Modifiers & (Modifiers.ABSTRACT | Modifiers.VIRTUAL)) != 0 && best_candidate.DeclaringType != InstanceExpression.Type) {
7113 var filter = new MemberFilter (best_candidate.Name, 0, MemberKind.Property, null, null);
7114 var p = MemberCache.FindMember (InstanceExpression.Type, filter, BindingRestriction.InstanceOnly | BindingRestriction.OverrideOnly) as PropertySpec;
7116 type = p.MemberType;
7120 DoBestMemberChecks (rc, best_candidate);
7122 // Handling of com-imported properties with any number of default property parameters
7123 if (best_candidate.HasGet && !best_candidate.Get.Parameters.IsEmpty) {
7124 var p = best_candidate.Get.Parameters;
7125 arguments = new Arguments (p.Count);
7126 for (int i = 0; i < p.Count; ++i) {
7127 arguments.Add (new Argument (OverloadResolver.ResolveDefaultValueArgument (rc, p.Types [i], p.FixedParameters [i].DefaultValue, loc)));
7129 } else if (best_candidate.HasSet && best_candidate.Set.Parameters.Count > 1) {
7130 var p = best_candidate.Set.Parameters;
7131 arguments = new Arguments (p.Count - 1);
7132 for (int i = 0; i < p.Count - 1; ++i) {
7133 arguments.Add (new Argument (OverloadResolver.ResolveDefaultValueArgument (rc, p.Types [i], p.FixedParameters [i].DefaultValue, loc)));
7140 protected override bool ResolveAutopropertyAssignment (ResolveContext rc, Expression rhs)
7142 if (!rc.HasSet (ResolveContext.Options.ConstructorScope))
7145 var prop = best_candidate.MemberDefinition as Property;
7146 if (prop == null || prop.Parent.PartialContainer != rc.CurrentMemberDefinition.Parent.PartialContainer) {
7147 var ps = MemberCache.FindMember (rc.CurrentType, MemberFilter.Property (best_candidate.Name, best_candidate.MemberType), BindingRestriction.DeclaredOnly) as PropertySpec;
7151 prop = (Property)ps.MemberDefinition;
7154 var spec = prop.BackingField;
7158 if (rc.IsStatic != spec.IsStatic)
7161 if (!spec.IsStatic && (!(InstanceExpression is This) || InstanceExpression is BaseThis))
7164 backing_field = new FieldExpr (prop.BackingField, loc);
7165 backing_field.ResolveLValue (rc, rhs);
7169 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
7171 if (!best_candidate.IsAccessible (rc))
7172 ErrorIsInaccesible (rc, best_candidate.GetSignatureForError (), expr.Location);
7174 best_candidate.CheckObsoleteness (rc, expr.Location);
7177 public void SetBackingFieldAssigned (FlowAnalysisContext fc)
7179 if (backing_field != null) {
7180 backing_field.SetFieldAssigned (fc);
7184 if (!IsAutoPropertyAccess)
7187 var prop = best_candidate.MemberDefinition as Property;
7188 if (prop != null && prop.BackingField != null) {
7189 bool lvalue_instance = best_candidate.DeclaringType.IsStruct;
7190 if (lvalue_instance) {
7191 var var = InstanceExpression as IVariableReference;
7192 if (var != null && var.VariableInfo != null) {
7193 fc.SetStructFieldAssigned (var.VariableInfo, prop.BackingField.Name);
7199 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
7201 Error_TypeArgumentsCannotBeUsed (ec, "property", GetSignatureForError (), loc);
7205 abstract class PropertyOrIndexerExpr<T> : MemberExpr, IDynamicAssign where T : PropertySpec
7207 // getter and setter can be different for base calls
7208 MethodSpec getter, setter;
7209 protected T best_candidate;
7211 protected LocalTemporary temp;
7212 protected bool emitting_compound_assignment;
7213 protected bool has_await_arguments;
7215 protected PropertyOrIndexerExpr (Location l)
7222 protected abstract Arguments Arguments { get; set; }
7224 public MethodSpec Getter {
7233 public MethodSpec Setter {
7244 protected override Expression DoResolve (ResolveContext ec)
7246 if (eclass == ExprClass.Unresolved) {
7247 ResolveConditionalAccessReceiver (ec);
7249 var expr = OverloadResolve (ec, null);
7254 using (ec.With (ResolveContext.Options.DontSetConditionalAccessReceiver, conditional_access_receiver))
7255 return expr.Resolve (ec);
7258 if (conditional_access_receiver) {
7259 type = LiftMemberType (ec, type);
7263 if (!ResolveGetter (ec))
7269 public override Expression DoResolveLValue (ResolveContext rc, Expression right_side)
7271 if (HasConditionalAccess ())
7272 Error_NullPropagatingLValue (rc);
7274 if (right_side == EmptyExpression.OutAccess) {
7275 // TODO: best_candidate can be null at this point
7276 INamedBlockVariable variable = null;
7277 if (best_candidate != null && rc.CurrentBlock.ParametersBlock.TopBlock.GetLocalName (best_candidate.Name, rc.CurrentBlock, ref variable) && variable is Linq.RangeVariable) {
7278 rc.Report.Error (1939, loc, "A range variable `{0}' may not be passes as `ref' or `out' parameter",
7279 best_candidate.Name);
7281 right_side.DoResolveLValue (rc, this);
7286 if (eclass == ExprClass.Unresolved) {
7287 var expr = OverloadResolve (rc, right_side);
7292 return expr.ResolveLValue (rc, right_side);
7294 ResolveInstanceExpression (rc, right_side);
7297 if (!best_candidate.HasSet) {
7298 if (ResolveAutopropertyAssignment (rc, right_side))
7301 rc.Report.Error (200, loc, "Property or indexer `{0}' cannot be assigned to (it is read-only)",
7302 GetSignatureForError ());
7306 if (!best_candidate.Set.IsAccessible (rc) || !best_candidate.Set.DeclaringType.IsAccessible (rc)) {
7307 if (best_candidate.HasDifferentAccessibility) {
7308 rc.Report.SymbolRelatedToPreviousError (best_candidate.Set);
7309 rc.Report.Error (272, loc, "The property or indexer `{0}' cannot be used in this context because the set accessor is inaccessible",
7310 GetSignatureForError ());
7312 rc.Report.SymbolRelatedToPreviousError (best_candidate.Set);
7313 ErrorIsInaccesible (rc, best_candidate.GetSignatureForError (), loc);
7317 if (best_candidate.HasDifferentAccessibility)
7318 CheckProtectedMemberAccess (rc, best_candidate.Set);
7320 setter = CandidateToBaseOverride (rc, best_candidate.Set);
7324 void EmitConditionalAccess (EmitContext ec, ref CallEmitter call, MethodSpec method, Arguments arguments)
7326 var ca = ec.ConditionalAccess;
7327 ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
7329 call.Emit (ec, method, arguments, loc);
7331 ec.CloseConditionalAccess (method.ReturnType != type && type.IsNullableType ? type : null);
7332 ec.ConditionalAccess = ca;
7336 // Implements the IAssignMethod interface for assignments
7338 public virtual void Emit (EmitContext ec, bool leave_copy)
7340 var call = new CallEmitter ();
7341 call.ConditionalAccess = ConditionalAccess;
7342 call.InstanceExpression = InstanceExpression;
7343 if (has_await_arguments)
7344 call.HasAwaitArguments = true;
7346 call.DuplicateArguments = emitting_compound_assignment;
7348 if (conditional_access_receiver)
7349 EmitConditionalAccess (ec, ref call, Getter, Arguments);
7351 call.Emit (ec, Getter, Arguments, loc);
7353 if (call.HasAwaitArguments) {
7354 InstanceExpression = call.InstanceExpression;
7355 Arguments = call.EmittedArguments;
7356 has_await_arguments = true;
7360 ec.Emit (OpCodes.Dup);
7361 temp = new LocalTemporary (Type);
7366 public abstract void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound);
7368 public override void Emit (EmitContext ec)
7373 protected override FieldExpr EmitToFieldSource (EmitContext ec)
7375 has_await_arguments = true;
7380 public abstract SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source);
7382 protected abstract Expression OverloadResolve (ResolveContext rc, Expression right_side);
7384 bool ResolveGetter (ResolveContext rc)
7386 if (!best_candidate.HasGet) {
7387 if (InstanceExpression != EmptyExpression.Null) {
7388 rc.Report.SymbolRelatedToPreviousError (best_candidate);
7389 rc.Report.Error (154, loc, "The property or indexer `{0}' cannot be used in this context because it lacks the `get' accessor",
7390 best_candidate.GetSignatureForError ());
7393 } else if (!best_candidate.Get.IsAccessible (rc) || !best_candidate.Get.DeclaringType.IsAccessible (rc)) {
7394 if (best_candidate.HasDifferentAccessibility) {
7395 rc.Report.SymbolRelatedToPreviousError (best_candidate.Get);
7396 rc.Report.Error (271, loc, "The property or indexer `{0}' cannot be used in this context because the get accessor is inaccessible",
7397 TypeManager.CSharpSignature (best_candidate));
7399 rc.Report.SymbolRelatedToPreviousError (best_candidate.Get);
7400 ErrorIsInaccesible (rc, best_candidate.Get.GetSignatureForError (), loc);
7404 if (best_candidate.HasDifferentAccessibility) {
7405 CheckProtectedMemberAccess (rc, best_candidate.Get);
7408 getter = CandidateToBaseOverride (rc, best_candidate.Get);
7412 protected virtual bool ResolveAutopropertyAssignment (ResolveContext rc, Expression rhs)
7419 /// Fully resolved expression that evaluates to an Event
7421 public class EventExpr : MemberExpr, IAssignMethod
7423 readonly EventSpec spec;
7426 public EventExpr (EventSpec spec, Location loc)
7434 protected override TypeSpec DeclaringType {
7436 return spec.DeclaringType;
7440 public override string Name {
7446 public override bool IsInstance {
7448 return !spec.IsStatic;
7452 public override bool IsStatic {
7454 return spec.IsStatic;
7458 public override string KindName {
7459 get { return "event"; }
7462 public MethodSpec Operator {
7470 public override MemberExpr ResolveMemberAccess (ResolveContext ec, Expression left, SimpleName original)
7473 // If the event is local to this class and we are not lhs of +=/-= we transform ourselves into a FieldExpr
7475 if (!ec.HasSet (ResolveContext.Options.CompoundAssignmentScope)) {
7476 if (spec.BackingField != null &&
7477 (spec.DeclaringType == ec.CurrentType || TypeManager.IsNestedChildOf (ec.CurrentType, spec.DeclaringType.MemberDefinition))) {
7479 spec.MemberDefinition.SetIsUsed ();
7481 spec.CheckObsoleteness (ec, loc);
7483 if ((spec.Modifiers & (Modifiers.ABSTRACT | Modifiers.EXTERN)) != 0)
7484 Error_AssignmentEventOnly (ec);
7486 FieldExpr ml = new FieldExpr (spec.BackingField, loc);
7488 InstanceExpression = null;
7490 return ml.ResolveMemberAccess (ec, left, original);
7494 return base.ResolveMemberAccess (ec, left, original);
7497 public override Expression CreateExpressionTree (ResolveContext ec)
7499 throw new NotSupportedException ("ET");
7502 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
7504 if (right_side == EmptyExpression.EventAddition) {
7505 op = spec.AccessorAdd;
7506 } else if (right_side == EmptyExpression.EventSubtraction) {
7507 op = spec.AccessorRemove;
7511 Error_AssignmentEventOnly (ec);
7515 if (HasConditionalAccess ())
7516 Error_NullPropagatingLValue (ec);
7518 op = CandidateToBaseOverride (ec, op);
7522 protected override Expression DoResolve (ResolveContext ec)
7524 eclass = ExprClass.EventAccess;
7525 type = spec.MemberType;
7527 ResolveInstanceExpression (ec, null);
7529 if (!ec.HasSet (ResolveContext.Options.CompoundAssignmentScope)) {
7530 Error_AssignmentEventOnly (ec);
7533 DoBestMemberChecks (ec, spec);
7537 public override void Emit (EmitContext ec)
7539 throw new NotSupportedException ();
7540 //Error_CannotAssign ();
7543 #region IAssignMethod Members
7545 public void Emit (EmitContext ec, bool leave_copy)
7547 throw new NotImplementedException ();
7550 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
7552 if (leave_copy || !isCompound)
7553 throw new NotImplementedException ("EventExpr::EmitAssign");
7555 Arguments args = new Arguments (1);
7556 args.Add (new Argument (source));
7558 // TODO: Wrong, needs receiver
7559 // if (NullShortCircuit) {
7560 // ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
7563 var call = new CallEmitter ();
7564 call.InstanceExpression = InstanceExpression;
7565 call.ConditionalAccess = ConditionalAccess;
7566 call.EmitStatement (ec, op, args, loc);
7568 // if (NullShortCircuit)
7569 // ec.CloseConditionalAccess (null);
7574 void Error_AssignmentEventOnly (ResolveContext ec)
7576 if (spec.DeclaringType == ec.CurrentType || TypeManager.IsNestedChildOf (ec.CurrentType, spec.DeclaringType.MemberDefinition)) {
7577 ec.Report.Error (79, loc,
7578 "The event `{0}' can only appear on the left hand side of `+=' or `-=' operator",
7579 GetSignatureForError ());
7581 ec.Report.Error (70, loc,
7582 "The event `{0}' can only appear on the left hand side of += or -= when used outside of the type `{1}'",
7583 GetSignatureForError (), spec.DeclaringType.GetSignatureForError ());
7587 protected override void Error_CannotCallAbstractBase (ResolveContext rc, string name)
7589 name = name.Substring (0, name.LastIndexOf ('.'));
7590 base.Error_CannotCallAbstractBase (rc, name);
7593 public override string GetSignatureForError ()
7595 return TypeManager.CSharpSignature (spec);
7598 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
7600 spec.CheckObsoleteness (rc, expr.Location);
7603 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
7605 Error_TypeArgumentsCannotBeUsed (ec, "event", GetSignatureForError (), loc);
7609 public class TemporaryVariableReference : VariableReference
7611 public class Declarator : Statement
7613 TemporaryVariableReference variable;
7615 public Declarator (TemporaryVariableReference variable)
7617 this.variable = variable;
7621 protected override void DoEmit (EmitContext ec)
7623 variable.li.CreateBuilder (ec);
7626 public override void Emit (EmitContext ec)
7628 // Don't create sequence point
7632 protected override bool DoFlowAnalysis (FlowAnalysisContext fc)
7637 protected override void CloneTo (CloneContext clonectx, Statement target)
7645 public TemporaryVariableReference (LocalVariable li, Location loc)
7648 this.type = li.Type;
7652 public override bool IsLockedByStatement {
7660 public LocalVariable LocalInfo {
7666 public static TemporaryVariableReference Create (TypeSpec type, Block block, Location loc, bool writeToSymbolFile = false)
7668 var li = LocalVariable.CreateCompilerGenerated (type, block, loc, writeToSymbolFile);
7669 return new TemporaryVariableReference (li, loc);
7672 protected override Expression DoResolve (ResolveContext ec)
7674 eclass = ExprClass.Variable;
7677 // Don't capture temporary variables except when using
7678 // state machine redirection and block yields
7680 if (ec.CurrentAnonymousMethod is StateMachineInitializer &&
7681 (ec.CurrentBlock.Explicit.HasYield || ec.CurrentBlock.Explicit.HasAwait) &&
7682 ec.IsVariableCapturingRequired) {
7683 AnonymousMethodStorey storey = li.Block.Explicit.CreateAnonymousMethodStorey (ec);
7684 storey.CaptureLocalVariable (ec, li);
7690 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
7692 return Resolve (ec);
7695 public override void Emit (EmitContext ec)
7697 li.CreateBuilder (ec);
7702 public void EmitAssign (EmitContext ec, Expression source)
7704 li.CreateBuilder (ec);
7706 EmitAssign (ec, source, false, false);
7709 public override HoistedVariable GetHoistedVariable (AnonymousExpression ae)
7711 return li.HoistedVariant;
7714 public override bool IsFixed {
7715 get { return true; }
7718 public override bool IsRef {
7719 get { return false; }
7722 public override string Name {
7723 get { throw new NotImplementedException (); }
7726 public override void SetHasAddressTaken ()
7728 throw new NotImplementedException ();
7731 protected override ILocalVariable Variable {
7735 public override VariableInfo VariableInfo {
7736 get { return null; }
7741 /// Handles `var' contextual keyword; var becomes a keyword only
7742 /// if no type called var exists in a variable scope
7744 class VarExpr : SimpleName
7746 public VarExpr (Location loc)
7751 public bool InferType (ResolveContext ec, Expression right_side)
7754 throw new InternalErrorException ("An implicitly typed local variable could not be redefined");
7756 type = right_side.Type;
7757 if (type == InternalType.NullLiteral || type.Kind == MemberKind.Void || type == InternalType.AnonymousMethod || type == InternalType.MethodGroup) {
7758 ec.Report.Error (815, loc,
7759 "An implicitly typed local variable declaration cannot be initialized with `{0}'",
7760 type.GetSignatureForError ());
7761 type = InternalType.ErrorType;
7765 eclass = ExprClass.Variable;
7769 protected override void Error_TypeOrNamespaceNotFound (IMemberContext ec)
7771 if (ec.Module.Compiler.Settings.Version < LanguageVersion.V_3)
7772 base.Error_TypeOrNamespaceNotFound (ec);
7774 ec.Module.Compiler.Report.Error (825, loc, "The contextual keyword `var' may only appear within a local variable declaration");