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
4786 if (candidate_pd.Count < best_pd.Count) {
4787 if (!candidate_params && !candidate_pd.FixedParameters [j - 1].HasDefaultValue) {
4790 } else if (candidate_pd.Count == best_pd.Count) {
4791 if (candidate_params)
4794 if (!candidate_pd.FixedParameters [j - 1].HasDefaultValue && best_pd.FixedParameters [j - 1].HasDefaultValue)
4797 if (candidate_pd.FixedParameters [j - 1].HasDefaultValue && best_pd.HasParams)
4805 // If candidate is applicable in its normal form and best has a params array and is applicable
4806 // only in its expanded form, then candidate is better
4808 if (candidate_params != best_params)
4809 return !candidate_params;
4812 // We have not reached end of parameters list due to params or used default parameters
4814 bool defaults_ambiguity = false;
4815 while (j < candidate_pd.Count && j < best_pd.Count) {
4816 var cand_param = candidate_pd.FixedParameters [j];
4817 var best_param = best_pd.FixedParameters [j];
4819 if (cand_param.HasDefaultValue != best_param.HasDefaultValue && (!candidate_pd.HasParams || !best_pd.HasParams))
4820 return cand_param.HasDefaultValue;
4822 defaults_ambiguity = true;
4823 if (candidate_pd.Count == best_pd.Count) {
4827 // void Foo (int i = 0) is better than void Foo (params int[]) for Foo ()
4828 // void Foo (string[] s, string value = null) is better than Foo (string s, params string[]) for Foo (null) or Foo ()
4830 if (cand_param.HasDefaultValue) {
4839 // Neither is better when not all arguments are provided
4841 // void Foo (string s, int i = 0) <-> Foo (string s, int i = 0, int i2 = 0)
4842 // void Foo (string s, int i = 0) <-> Foo (string s, byte i = 0)
4843 // void Foo (string s, params int[]) <-> Foo (string s, params byte[])
4848 if (candidate_pd.Count != best_pd.Count) {
4849 if (defaults_ambiguity && best_pd.Count - 1 == j)
4850 return best_pd.HasParams;
4852 return candidate_pd.Count < best_pd.Count;
4856 // One is a non-generic method and second is a generic method, then non-generic is better
4858 if (best.IsGeneric != candidate.IsGeneric)
4859 return best.IsGeneric;
4862 // Both methods have the same number of parameters, and the parameters have equal types
4863 // Pick the "more specific" signature using rules over original (non-inflated) types
4865 var candidate_def_pd = ((IParametersMember) candidate.MemberDefinition).Parameters;
4866 var best_def_pd = ((IParametersMember) best.MemberDefinition).Parameters;
4868 bool specific_at_least_once = false;
4869 for (j = 0; j < args_count; ++j) {
4870 NamedArgument na = args_count == 0 ? null : args [j] as NamedArgument;
4872 ct = candidate_def_pd.Types[cparam.GetParameterIndexByName (na.Name)];
4873 bt = best_def_pd.Types[bparam.GetParameterIndexByName (na.Name)];
4875 ct = candidate_def_pd.Types[j];
4876 bt = best_def_pd.Types[j];
4881 TypeSpec specific = MoreSpecific (ct, bt);
4885 specific_at_least_once = true;
4888 if (specific_at_least_once)
4894 static bool CheckInflatedArguments (MethodSpec ms)
4896 if (!TypeParameterSpec.HasAnyTypeParameterTypeConstrained (ms.GenericDefinition))
4899 // Setup constraint checker for probing only
4900 ConstraintChecker cc = new ConstraintChecker (null);
4902 var mp = ms.Parameters.Types;
4903 for (int i = 0; i < mp.Length; ++i) {
4904 var type = mp[i] as InflatedTypeSpec;
4908 var targs = type.TypeArguments;
4909 if (targs.Length == 0)
4912 // TODO: Checking inflated MVAR arguments should be enough
4913 if (!cc.CheckAll (type.GetDefinition (), targs, type.Constraints, Location.Null))
4920 public static void Error_ConstructorMismatch (ResolveContext rc, TypeSpec type, int argCount, Location loc)
4922 rc.Report.Error (1729, loc,
4923 "The type `{0}' does not contain a constructor that takes `{1}' arguments",
4924 type.GetSignatureForError (), argCount.ToString ());
4928 // Determines if the candidate method is applicable to the given set of arguments
4929 // There could be two different set of parameters for same candidate where one
4930 // is the closest override for default values and named arguments checks and second
4931 // one being the virtual base for the parameter types and modifiers.
4933 // A return value rates candidate method compatibility,
4935 // 0 = the best, int.MaxValue = the worst
4937 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)
4940 // Each step has allocated 10 values, it can overflow for
4941 // more than 10 arguments but that's ok as it's used for
4942 // better error reporting only
4944 const int ArgumentCountMismatch = 1000000000;
4945 const int NamedArgumentsMismatch = 100000000;
4946 const int DefaultArgumentMismatch = 10000000;
4947 const int UnexpectedTypeArguments = 1000000;
4948 const int TypeArgumentsMismatch = 100000;
4949 const int InflatedTypesMismatch = 10000;
4951 // Parameters of most-derived type used mainly for named and optional parameters
4952 var pd = pm.Parameters;
4954 // Used for params modifier only, that's legacy of C# 1.0 which uses base type for
4955 // params modifier instead of most-derived type
4956 var cpd = ((IParametersMember) candidate).Parameters;
4957 int param_count = pd.Count;
4958 int optional_count = 0;
4960 Arguments orig_args = arguments;
4962 if (arg_count != param_count) {
4964 // No arguments expansion when doing exact match for delegates
4966 if ((restrictions & Restrictions.CovariantDelegate) == 0) {
4967 for (int i = 0; i < pd.Count; ++i) {
4968 if (pd.FixedParameters[i].HasDefaultValue) {
4969 optional_count = pd.Count - i;
4975 if (optional_count != 0) {
4976 // Readjust expected number when params used
4977 if (cpd.HasParams) {
4979 if (arg_count < param_count)
4981 } else if (arg_count > param_count) {
4982 int args_gap = System.Math.Abs (arg_count - param_count);
4983 return ArgumentCountMismatch + args_gap;
4984 } else if (arg_count < param_count - optional_count) {
4985 int args_gap = System.Math.Abs (param_count - optional_count - arg_count);
4986 return ArgumentCountMismatch + args_gap;
4988 } else if (arg_count != param_count) {
4989 int args_gap = System.Math.Abs (arg_count - param_count);
4991 return ArgumentCountMismatch + args_gap;
4992 if (arg_count < param_count - 1)
4993 return ArgumentCountMismatch + args_gap;
4996 // Resize to fit optional arguments
4997 if (optional_count != 0) {
4998 if (arguments == null) {
4999 arguments = new Arguments (optional_count);
5001 // Have to create a new container, so the next run can do same
5002 var resized = new Arguments (param_count);
5003 resized.AddRange (arguments);
5004 arguments = resized;
5007 for (int i = arg_count; i < param_count; ++i)
5008 arguments.Add (null);
5012 if (arg_count > 0) {
5014 // Shuffle named arguments to the right positions if there are any
5016 if (arguments[arg_count - 1] is NamedArgument) {
5017 arg_count = arguments.Count;
5019 for (int i = 0; i < arg_count; ++i) {
5020 bool arg_moved = false;
5022 NamedArgument na = arguments[i] as NamedArgument;
5026 int index = pd.GetParameterIndexByName (na.Name);
5028 // Named parameter not found
5030 return NamedArgumentsMismatch - i;
5032 // already reordered
5037 if (index >= param_count) {
5038 // When using parameters which should not be available to the user
5039 if ((cpd.FixedParameters[index].ModFlags & Parameter.Modifier.PARAMS) == 0)
5042 arguments.Add (null);
5046 if (index == arg_count)
5047 return NamedArgumentsMismatch - i - 1;
5049 temp = arguments [index];
5051 // The slot has been taken by positional argument
5052 if (temp != null && !(temp is NamedArgument))
5057 arguments = arguments.MarkOrderedArgument (na);
5061 if (arguments == orig_args) {
5062 arguments = new Arguments (orig_args.Count);
5063 arguments.AddRange (orig_args);
5066 arguments[index] = arguments[i];
5067 arguments[i] = temp;
5074 arg_count = arguments.Count;
5076 } else if (arguments != null) {
5077 arg_count = arguments.Count;
5081 // Don't do any expensive checks when the candidate cannot succeed
5083 if (arg_count != param_count && !cpd.HasParams)
5084 return DefaultArgumentMismatch - System.Math.Abs (param_count - arg_count);
5086 var dep = candidate.GetMissingDependencies ();
5088 ImportedTypeDefinition.Error_MissingDependency (ec, dep, loc);
5093 // 1. Handle generic method using type arguments when specified or type inference
5096 var ms = candidate as MethodSpec;
5097 if (ms != null && ms.IsGeneric) {
5098 if (type_arguments != null) {
5099 var g_args_count = ms.Arity;
5100 if (g_args_count != type_arguments.Count)
5101 return TypeArgumentsMismatch - System.Math.Abs (type_arguments.Count - g_args_count);
5103 if (type_arguments.Arguments != null)
5104 ms = ms.MakeGenericMethod (ec, type_arguments.Arguments);
5107 // Deploy custom error reporting for infered anonymous expression or lambda methods. When
5108 // probing lambda methods keep all errors reported in separate set and once we are done and no best
5109 // candidate was found use the set to report more details about what was wrong with lambda body.
5110 // The general idea is to distinguish between code errors and errors caused by
5111 // trial-and-error type inference
5113 if (lambda_conv_msgs == null) {
5114 for (int i = 0; i < arg_count; i++) {
5115 Argument a = arguments[i];
5119 var am = a.Expr as AnonymousMethodExpression;
5121 if (lambda_conv_msgs == null)
5122 lambda_conv_msgs = new SessionReportPrinter ();
5124 am.TypeInferenceReportPrinter = lambda_conv_msgs;
5129 var ti = new TypeInference (arguments);
5130 TypeSpec[] i_args = ti.InferMethodArguments (ec, ms);
5133 return TypeArgumentsMismatch - ti.InferenceScore;
5136 // Clear any error messages when the result was success
5138 if (lambda_conv_msgs != null)
5139 lambda_conv_msgs.ClearSession ();
5141 if (i_args.Length != 0) {
5143 for (int i = 0; i < i_args.Length; ++i) {
5144 var ta = i_args [i];
5145 if (!ta.IsAccessible (ec))
5146 return TypeArgumentsMismatch - i;
5150 ms = ms.MakeGenericMethod (ec, i_args);
5155 // Type arguments constraints have to match for the method to be applicable
5157 if (!CheckInflatedArguments (ms)) {
5159 return InflatedTypesMismatch;
5163 // We have a generic return type and at same time the method is override which
5164 // means we have to also inflate override return type in case the candidate is
5165 // best candidate and override return type is different to base return type.
5167 // virtual Foo<T, object> with override Foo<T, dynamic>
5169 if (candidate != pm) {
5170 MethodSpec override_ms = (MethodSpec) pm;
5171 var inflator = new TypeParameterInflator (ec, ms.DeclaringType, override_ms.GenericDefinition.TypeParameters, ms.TypeArguments);
5172 returnType = inflator.Inflate (returnType);
5174 returnType = ms.ReturnType;
5181 if (type_arguments != null)
5182 return UnexpectedTypeArguments;
5188 // 2. Each argument has to be implicitly convertible to method parameter
5190 Parameter.Modifier p_mod = 0;
5193 for (int i = 0; i < arg_count; i++) {
5194 Argument a = arguments[i];
5196 var fp = pd.FixedParameters[i];
5197 if (!fp.HasDefaultValue) {
5198 arguments = orig_args;
5199 return arg_count * 2 + 2;
5203 // Get the default value expression, we can use the same expression
5204 // if the type matches
5206 Expression e = fp.DefaultValue;
5208 e = ResolveDefaultValueArgument (ec, ptypes[i], e, loc);
5210 // Restore for possible error reporting
5211 for (int ii = i; ii < arg_count; ++ii)
5212 arguments.RemoveAt (i);
5214 return (arg_count - i) * 2 + 1;
5218 if ((fp.ModFlags & Parameter.Modifier.CallerMask) != 0) {
5220 // LAMESPEC: Attributes can be mixed together with build-in priority
5222 if ((fp.ModFlags & Parameter.Modifier.CallerLineNumber) != 0) {
5223 e = new IntLiteral (ec.BuiltinTypes, loc.Row, loc);
5224 } else if ((fp.ModFlags & Parameter.Modifier.CallerFilePath) != 0) {
5225 e = new StringLiteral (ec.BuiltinTypes, loc.NameFullPath, loc);
5226 } else if (ec.MemberContext.CurrentMemberDefinition != null) {
5227 e = new StringLiteral (ec.BuiltinTypes, ec.MemberContext.CurrentMemberDefinition.GetCallerMemberName (), loc);
5231 arguments[i] = new Argument (e, Argument.AType.Default);
5235 if (p_mod != Parameter.Modifier.PARAMS) {
5236 p_mod = (pd.FixedParameters[i].ModFlags & ~Parameter.Modifier.PARAMS) | (cpd.FixedParameters[i].ModFlags & Parameter.Modifier.PARAMS);
5238 } else if (!params_expanded_form) {
5239 params_expanded_form = true;
5240 pt = ((ElementTypeSpec) pt).Element;
5246 if (!params_expanded_form) {
5247 if (a.IsExtensionType) {
5248 if (ExtensionMethodGroupExpr.IsExtensionTypeCompatible (a.Type, pt)) {
5253 score = IsArgumentCompatible (ec, a, p_mod, pt);
5256 dynamicArgument = true;
5261 // It can be applicable in expanded form (when not doing exact match like for delegates)
5263 if (score != 0 && (p_mod & Parameter.Modifier.PARAMS) != 0 && (restrictions & Restrictions.CovariantDelegate) == 0) {
5264 if (!params_expanded_form) {
5265 pt = ((ElementTypeSpec) pt).Element;
5269 score = IsArgumentCompatible (ec, a, Parameter.Modifier.NONE, pt);
5272 params_expanded_form = true;
5273 dynamicArgument = true;
5274 } else if (score == 0 || arg_count > pd.Count) {
5275 params_expanded_form = true;
5280 if (params_expanded_form)
5282 return (arg_count - i) * 2 + score;
5287 // Restore original arguments for dynamic binder to keep the intention of original source code
5289 if (dynamicArgument)
5290 arguments = orig_args;
5295 public static Expression ResolveDefaultValueArgument (ResolveContext ec, TypeSpec ptype, Expression e, Location loc)
5297 if (e is Constant && e.Type == ptype)
5301 // LAMESPEC: No idea what the exact rules are for System.Reflection.Missing.Value instead of null
5303 if (e == EmptyExpression.MissingValue && (ptype.BuiltinType == BuiltinTypeSpec.Type.Object || ptype.BuiltinType == BuiltinTypeSpec.Type.Dynamic)) {
5304 e = new MemberAccess (new MemberAccess (new MemberAccess (
5305 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "System", loc), "Reflection", loc), "Missing", loc), "Value", loc);
5306 } else if (e is Constant) {
5308 // Handles int to int? conversions, DefaultParameterValue check
5310 e = Convert.ImplicitConversionStandard (ec, e, ptype, loc);
5314 e = new DefaultValueExpression (new TypeExpression (ptype, loc), loc);
5317 return e.Resolve (ec);
5321 // Tests argument compatibility with the parameter
5322 // The possible return values are
5324 // 1 - modifier mismatch
5325 // 2 - type mismatch
5326 // -1 - dynamic binding required
5328 int IsArgumentCompatible (ResolveContext ec, Argument argument, Parameter.Modifier param_mod, TypeSpec parameter)
5331 // Types have to be identical when ref or out modifer
5332 // is used and argument is not of dynamic type
5334 if (((argument.Modifier | param_mod) & Parameter.Modifier.RefOutMask) != 0) {
5335 var arg_type = argument.Type;
5337 if ((argument.Modifier & Parameter.Modifier.RefOutMask) != (param_mod & Parameter.Modifier.RefOutMask)) {
5339 // Using dynamic for ref/out parameter can still succeed at runtime
5341 if (arg_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (argument.Modifier & Parameter.Modifier.RefOutMask) == 0 && (restrictions & Restrictions.CovariantDelegate) == 0)
5347 if (arg_type != parameter) {
5348 if (arg_type == InternalType.VarOutType)
5352 // Do full equality check after quick path
5354 if (!TypeSpecComparer.IsEqual (arg_type, parameter)) {
5356 // Using dynamic for ref/out parameter can still succeed at runtime
5358 if (arg_type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (argument.Modifier & Parameter.Modifier.RefOutMask) == 0 && (restrictions & Restrictions.CovariantDelegate) == 0)
5366 if (argument.Type.BuiltinType == BuiltinTypeSpec.Type.Dynamic && (restrictions & Restrictions.CovariantDelegate) == 0)
5370 // Use implicit conversion in all modes to return same candidates when the expression
5371 // is used as argument or delegate conversion
5373 if (!Convert.ImplicitConversionExists (ec, argument.Expr, parameter)) {
5374 return parameter.IsDelegate && argument.Expr is AnonymousMethodExpression ? 2 : 3;
5381 static TypeSpec MoreSpecific (TypeSpec p, TypeSpec q)
5383 if (TypeManager.IsGenericParameter (p) && !TypeManager.IsGenericParameter (q))
5385 if (!TypeManager.IsGenericParameter (p) && TypeManager.IsGenericParameter (q))
5388 var ac_p = p as ArrayContainer;
5390 var ac_q = q as ArrayContainer;
5394 TypeSpec specific = MoreSpecific (ac_p.Element, ac_q.Element);
5395 if (specific == ac_p.Element)
5397 if (specific == ac_q.Element)
5399 } else if (p.IsGeneric && q.IsGeneric) {
5400 var pargs = TypeManager.GetTypeArguments (p);
5401 var qargs = TypeManager.GetTypeArguments (q);
5403 bool p_specific_at_least_once = false;
5404 bool q_specific_at_least_once = false;
5406 for (int i = 0; i < pargs.Length; i++) {
5407 TypeSpec specific = MoreSpecific (pargs[i], qargs[i]);
5408 if (specific == pargs[i])
5409 p_specific_at_least_once = true;
5410 if (specific == qargs[i])
5411 q_specific_at_least_once = true;
5414 if (p_specific_at_least_once && !q_specific_at_least_once)
5416 if (!p_specific_at_least_once && q_specific_at_least_once)
5424 // Find the best method from candidate list
5426 public T ResolveMember<T> (ResolveContext rc, ref Arguments args) where T : MemberSpec, IParametersMember
5428 List<AmbiguousCandidate> ambiguous_candidates = null;
5430 MemberSpec best_candidate;
5431 Arguments best_candidate_args = null;
5432 bool best_candidate_params = false;
5433 bool best_candidate_dynamic = false;
5434 int best_candidate_rate;
5435 IParametersMember best_parameter_member = null;
5437 int args_count = args != null ? args.Count : 0;
5439 Arguments candidate_args = args;
5440 bool error_mode = false;
5441 MemberSpec invocable_member = null;
5442 int applicable_candidates = 0;
5445 best_candidate = null;
5446 best_candidate_rate = int.MaxValue;
5448 var type_members = members;
5450 for (int i = 0; i < type_members.Count; ++i) {
5451 var member = type_members[i];
5454 // Methods in a base class are not candidates if any method in a derived
5455 // class is applicable
5457 if ((member.Modifiers & Modifiers.OVERRIDE) != 0)
5461 if (!member.IsAccessible (rc))
5464 if (rc.IsRuntimeBinder && !member.DeclaringType.IsAccessible (rc))
5467 if ((member.Modifiers & (Modifiers.PROTECTED | Modifiers.STATIC)) == Modifiers.PROTECTED &&
5468 instance_qualifier != null && !instance_qualifier.CheckProtectedMemberAccess (rc, member)) {
5473 IParametersMember pm = member as IParametersMember;
5476 // Will use it later to report ambiguity between best method and invocable member
5478 if (Invocation.IsMemberInvocable (member))
5479 invocable_member = member;
5485 // Overload resolution is looking for base member but using parameter names
5486 // and default values from the closest member. That means to do expensive lookup
5487 // for the closest override for virtual or abstract members
5489 if ((member.Modifiers & (Modifiers.VIRTUAL | Modifiers.ABSTRACT)) != 0) {
5490 var override_params = base_provider.GetOverrideMemberParameters (member);
5491 if (override_params != null)
5492 pm = override_params;
5496 // Check if the member candidate is applicable
5498 bool params_expanded_form = false;
5499 bool dynamic_argument = false;
5500 TypeSpec rt = pm.MemberType;
5501 int candidate_rate = IsApplicable (rc, ref candidate_args, args_count, ref member, pm, ref params_expanded_form, ref dynamic_argument, ref rt, error_mode);
5503 if (lambda_conv_msgs != null)
5504 lambda_conv_msgs.EndSession ();
5507 // How does it score compare to others
5509 if (candidate_rate < best_candidate_rate) {
5511 // Fatal error (missing dependency), cannot continue
5512 if (candidate_rate < 0)
5515 applicable_candidates = 1;
5516 if ((restrictions & Restrictions.GetEnumeratorLookup) != 0 && candidate_args.Count != 0) {
5517 // Only parameterless methods are considered
5519 best_candidate_rate = candidate_rate;
5520 best_candidate = member;
5521 best_candidate_args = candidate_args;
5522 best_candidate_params = params_expanded_form;
5523 best_candidate_dynamic = dynamic_argument;
5524 best_parameter_member = pm;
5525 best_candidate_return_type = rt;
5527 } else if (candidate_rate == 0) {
5529 // The member look is done per type for most operations but sometimes
5530 // it's not possible like for binary operators overload because they
5531 // are unioned between 2 sides
5533 if ((restrictions & Restrictions.BaseMembersIncluded) != 0) {
5534 if (TypeSpec.IsBaseClass (best_candidate.DeclaringType, member.DeclaringType, true))
5538 ++applicable_candidates;
5540 if (best_candidate.DeclaringType.IsInterface && member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
5542 // We pack all interface members into top level type which makes the overload resolution
5543 // more complicated for interfaces. We compensate it by removing methods with same
5544 // signature when building the cache hence this path should not really be hit often
5547 // interface IA { void Foo (int arg); }
5548 // interface IB : IA { void Foo (params int[] args); }
5550 // IB::Foo is the best overload when calling IB.Foo (1)
5553 if (ambiguous_candidates != null) {
5554 foreach (var amb_cand in ambiguous_candidates) {
5555 if (member.DeclaringType.ImplementsInterface (best_candidate.DeclaringType, false)) {
5564 ambiguous_candidates = null;
5567 // Is the new candidate better
5568 is_better = BetterFunction (rc, candidate_args, member, pm.Parameters, params_expanded_form, best_candidate, best_parameter_member.Parameters, best_candidate_params);
5572 best_candidate = member;
5573 best_candidate_args = candidate_args;
5574 best_candidate_params = params_expanded_form;
5575 best_candidate_dynamic = dynamic_argument;
5576 best_parameter_member = pm;
5577 best_candidate_return_type = rt;
5579 // It's not better but any other found later could be but we are not sure yet
5580 if (ambiguous_candidates == null)
5581 ambiguous_candidates = new List<AmbiguousCandidate> ();
5583 ambiguous_candidates.Add (new AmbiguousCandidate (member, pm.Parameters, params_expanded_form));
5587 // Restore expanded arguments
5588 candidate_args = args;
5590 } while (best_candidate_rate != 0 && (type_members = base_provider.GetBaseMembers (type_members[0].DeclaringType)) != null);
5593 // We've found exact match
5595 if (best_candidate_rate == 0)
5599 // Try extension methods lookup when no ordinary method match was found and provider enables it
5602 var emg = base_provider.LookupExtensionMethod (rc);
5604 emg = emg.OverloadResolve (rc, ref args, null, restrictions);
5606 best_candidate_extension_group = emg;
5607 return (T) (MemberSpec) emg.BestCandidate;
5612 // Don't run expensive error reporting mode for probing
5619 if (lambda_conv_msgs != null && !lambda_conv_msgs.IsEmpty)
5622 lambda_conv_msgs = null;
5627 // No best member match found, report an error
5629 if (best_candidate_rate != 0 || error_mode) {
5630 ReportOverloadError (rc, best_candidate, best_parameter_member, best_candidate_args, best_candidate_params);
5634 if (best_candidate_dynamic) {
5635 if (args[0].IsExtensionType) {
5636 rc.Report.Error (1973, loc,
5637 "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",
5638 args [0].Type.GetSignatureForError (), best_candidate.Name, best_candidate.GetSignatureForError ());
5642 // Check type constraints only when explicit type arguments are used
5644 if (applicable_candidates == 1 && best_candidate.IsGeneric && type_arguments != null) {
5645 MethodSpec bc = best_candidate as MethodSpec;
5646 if (bc != null && TypeParameterSpec.HasAnyTypeParameterConstrained (bc.GenericDefinition)) {
5647 ConstraintChecker cc = new ConstraintChecker (rc);
5648 cc.CheckAll (bc.GetGenericMethodDefinition (), bc.TypeArguments, bc.Constraints, loc);
5652 BestCandidateIsDynamic = true;
5657 // These flags indicates we are running delegate probing conversion. No need to
5658 // do more expensive checks
5660 if ((restrictions & (Restrictions.ProbingOnly | Restrictions.CovariantDelegate)) == (Restrictions.CovariantDelegate | Restrictions.ProbingOnly))
5661 return (T) best_candidate;
5663 if (ambiguous_candidates != null) {
5665 // Now check that there are no ambiguities i.e the selected method
5666 // should be better than all the others
5668 for (int ix = 0; ix < ambiguous_candidates.Count; ix++) {
5669 var candidate = ambiguous_candidates [ix];
5671 if (!BetterFunction (rc, best_candidate_args, best_candidate, best_parameter_member.Parameters, best_candidate_params, candidate.Member, candidate.Parameters, candidate.Expanded)) {
5672 var ambiguous = candidate.Member;
5673 if (custom_errors == null || !custom_errors.AmbiguousCandidates (rc, best_candidate, ambiguous)) {
5674 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5675 rc.Report.SymbolRelatedToPreviousError (ambiguous);
5676 rc.Report.Error (121, loc, "The call is ambiguous between the following methods or properties: `{0}' and `{1}'",
5677 best_candidate.GetSignatureForError (), ambiguous.GetSignatureForError ());
5680 return (T) best_candidate;
5685 if (invocable_member != null && !IsProbingOnly) {
5686 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5687 rc.Report.SymbolRelatedToPreviousError (invocable_member);
5688 rc.Report.Warning (467, 2, loc, "Ambiguity between method `{0}' and invocable non-method `{1}'. Using method group",
5689 best_candidate.GetSignatureForError (), invocable_member.GetSignatureForError ());
5693 // And now check if the arguments are all
5694 // compatible, perform conversions if
5695 // necessary etc. and return if everything is
5698 if (!VerifyArguments (rc, ref best_candidate_args, best_candidate, best_parameter_member, best_candidate_params))
5701 if (best_candidate == null)
5705 // Don't run possibly expensive checks in probing mode
5707 if (!IsProbingOnly && !rc.IsInProbingMode) {
5709 // Check ObsoleteAttribute on the best method
5711 best_candidate.CheckObsoleteness (rc, loc);
5713 best_candidate.MemberDefinition.SetIsUsed ();
5716 args = best_candidate_args;
5717 return (T) best_candidate;
5720 public MethodSpec ResolveOperator (ResolveContext rc, ref Arguments args)
5722 return ResolveMember<MethodSpec> (rc, ref args);
5725 void ReportArgumentMismatch (ResolveContext ec, int idx, MemberSpec method,
5726 Argument a, AParametersCollection expected_par, TypeSpec paramType)
5728 if (custom_errors != null && custom_errors.ArgumentMismatch (ec, method, a, idx))
5731 if (a.Type == InternalType.ErrorType)
5734 if (a is CollectionElementInitializer.ElementInitializerArgument) {
5735 ec.Report.SymbolRelatedToPreviousError (method);
5736 if ((expected_par.FixedParameters[idx].ModFlags & Parameter.Modifier.RefOutMask) != 0) {
5737 ec.Report.Error (1954, loc, "The best overloaded collection initalizer method `{0}' cannot have `ref' or `out' modifier",
5738 TypeManager.CSharpSignature (method));
5741 ec.Report.Error (1950, loc, "The best overloaded collection initalizer method `{0}' has some invalid arguments",
5742 TypeManager.CSharpSignature (method));
5743 } else if (IsDelegateInvoke) {
5744 ec.Report.Error (1594, loc, "Delegate `{0}' has some invalid arguments",
5745 DelegateType.GetSignatureForError ());
5747 ec.Report.SymbolRelatedToPreviousError (method);
5748 ec.Report.Error (1502, loc, "The best overloaded method match for `{0}' has some invalid arguments",
5749 method.GetSignatureForError ());
5752 Parameter.Modifier mod = idx >= expected_par.Count ? 0 : expected_par.FixedParameters[idx].ModFlags;
5754 string index = (idx + 1).ToString ();
5755 if (((mod & Parameter.Modifier.RefOutMask) ^ (a.Modifier & Parameter.Modifier.RefOutMask)) != 0) {
5756 if ((mod & Parameter.Modifier.RefOutMask) == 0)
5757 ec.Report.Error (1615, a.Expr.Location, "Argument `#{0}' does not require `{1}' modifier. Consider removing `{1}' modifier",
5758 index, Parameter.GetModifierSignature (a.Modifier));
5760 ec.Report.Error (1620, a.Expr.Location, "Argument `#{0}' is missing `{1}' modifier",
5761 index, Parameter.GetModifierSignature (mod));
5763 string p1 = a.GetSignatureForError ();
5764 string p2 = paramType.GetSignatureForError ();
5767 p1 = a.Type.GetSignatureForErrorIncludingAssemblyName ();
5768 p2 = paramType.GetSignatureForErrorIncludingAssemblyName ();
5771 if ((mod & Parameter.Modifier.RefOutMask) != 0) {
5772 p1 = Parameter.GetModifierSignature (a.Modifier) + " " + p1;
5773 p2 = Parameter.GetModifierSignature (a.Modifier) + " " + p2;
5776 ec.Report.Error (1503, a.Expr.Location,
5777 "Argument `#{0}' cannot convert `{1}' expression to type `{2}'", index, p1, p2);
5782 // We have failed to find exact match so we return error info about the closest match
5784 void ReportOverloadError (ResolveContext rc, MemberSpec best_candidate, IParametersMember pm, Arguments args, bool params_expanded)
5786 int ta_count = type_arguments == null ? 0 : type_arguments.Count;
5787 int arg_count = args == null ? 0 : args.Count;
5789 if (ta_count != best_candidate.Arity && (ta_count > 0 || ((IParametersMember) best_candidate).Parameters.IsEmpty)) {
5790 var mg = new MethodGroupExpr (new [] { best_candidate }, best_candidate.DeclaringType, loc);
5791 mg.Error_TypeArgumentsCannotBeUsed (rc, best_candidate, loc);
5795 if (lambda_conv_msgs != null && lambda_conv_msgs.Merge (rc.Report.Printer)) {
5800 if ((best_candidate.Modifiers & (Modifiers.PROTECTED | Modifiers.STATIC)) == Modifiers.PROTECTED &&
5801 InstanceQualifier != null && !InstanceQualifier.CheckProtectedMemberAccess (rc, best_candidate)) {
5802 MemberExpr.Error_ProtectedMemberAccess (rc, best_candidate, InstanceQualifier.InstanceType, loc);
5806 // For candidates which match on parameters count report more details about incorrect arguments
5809 if (pm.Parameters.Count == arg_count || params_expanded || HasUnfilledParams (best_candidate, pm, args)) {
5810 // Reject any inaccessible member
5811 if (!best_candidate.IsAccessible (rc) || !best_candidate.DeclaringType.IsAccessible (rc)) {
5812 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5813 Expression.ErrorIsInaccesible (rc, best_candidate.GetSignatureForError (), loc);
5817 var ms = best_candidate as MethodSpec;
5818 if (ms != null && ms.IsGeneric) {
5819 bool constr_ok = true;
5820 if (ms.TypeArguments != null)
5821 constr_ok = new ConstraintChecker (rc.MemberContext).CheckAll (ms.GetGenericMethodDefinition (), ms.TypeArguments, ms.Constraints, loc);
5823 if (ta_count == 0 && ms.TypeArguments == null) {
5824 if (custom_errors != null && custom_errors.TypeInferenceFailed (rc, best_candidate))
5828 rc.Report.Error (411, loc,
5829 "The type arguments for method `{0}' cannot be inferred from the usage. Try specifying the type arguments explicitly",
5830 ms.GetGenericMethodDefinition ().GetSignatureForError ());
5837 VerifyArguments (rc, ref args, best_candidate, pm, params_expanded);
5843 // We failed to find any method with correct argument count, report best candidate
5845 if (custom_errors != null && custom_errors.NoArgumentMatch (rc, best_candidate))
5848 if (best_candidate.Kind == MemberKind.Constructor) {
5849 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5850 Error_ConstructorMismatch (rc, best_candidate.DeclaringType, arg_count, loc);
5851 } else if (IsDelegateInvoke) {
5852 rc.Report.SymbolRelatedToPreviousError (DelegateType);
5853 rc.Report.Error (1593, loc, "Delegate `{0}' does not take `{1}' arguments",
5854 DelegateType.GetSignatureForError (), arg_count.ToString ());
5856 string name = best_candidate.Kind == MemberKind.Indexer ? "this" : best_candidate.Name;
5857 rc.Report.SymbolRelatedToPreviousError (best_candidate);
5858 rc.Report.Error (1501, loc, "No overload for method `{0}' takes `{1}' arguments",
5859 name, arg_count.ToString ());
5863 static bool HasUnfilledParams (MemberSpec best_candidate, IParametersMember pm, Arguments args)
5865 var p = ((IParametersMember)best_candidate).Parameters;
5870 for (int i = p.Count - 1; i != 0; --i) {
5871 var fp = p.FixedParameters [i];
5872 if ((fp.ModFlags & Parameter.Modifier.PARAMS) == 0)
5882 foreach (var arg in args) {
5883 var na = arg as NamedArgument;
5887 if (na.Name == name) {
5896 return args.Count + 1 == pm.Parameters.Count;
5899 bool VerifyArguments (ResolveContext ec, ref Arguments args, MemberSpec member, IParametersMember pm, bool chose_params_expanded)
5901 var pd = pm.Parameters;
5902 var cpd = ((IParametersMember) member).Parameters;
5903 var ptypes = cpd.Types;
5905 Parameter.Modifier p_mod = 0;
5907 int a_idx = 0, a_pos = 0;
5909 ArrayInitializer params_initializers = null;
5910 bool has_unsafe_arg = pm.MemberType.IsPointer;
5911 int arg_count = args == null ? 0 : args.Count;
5913 for (; a_idx < arg_count; a_idx++, ++a_pos) {
5918 if (p_mod != Parameter.Modifier.PARAMS) {
5919 p_mod = cpd.FixedParameters [a_idx].ModFlags;
5921 has_unsafe_arg |= pt.IsPointer;
5923 if (p_mod == Parameter.Modifier.PARAMS) {
5924 if (chose_params_expanded) {
5925 params_initializers = new ArrayInitializer (arg_count - a_idx, a.Expr.Location);
5926 pt = TypeManager.GetElementType (pt);
5932 // Types have to be identical when ref or out modifer is used
5934 if (((a.Modifier | p_mod) & Parameter.Modifier.RefOutMask) != 0) {
5935 if ((a.Modifier & Parameter.Modifier.RefOutMask) != (p_mod & Parameter.Modifier.RefOutMask))
5938 var arg_type = a.Type;
5942 if (arg_type == InternalType.VarOutType) {
5944 // Set underlying variable type based on parameter type
5946 ((DeclarationExpression)a.Expr).Variable.Type = pt;
5950 if (!TypeSpecComparer.IsEqual (arg_type, pt))
5954 NamedArgument na = a as NamedArgument;
5956 int name_index = pd.GetParameterIndexByName (na.Name);
5957 if (name_index < 0 || name_index >= pd.Count) {
5958 if (IsDelegateInvoke) {
5959 ec.Report.SymbolRelatedToPreviousError (DelegateType);
5960 ec.Report.Error (1746, na.Location,
5961 "The delegate `{0}' does not contain a parameter named `{1}'",
5962 DelegateType.GetSignatureForError (), na.Name);
5964 ec.Report.SymbolRelatedToPreviousError (member);
5965 ec.Report.Error (1739, na.Location,
5966 "The best overloaded method match for `{0}' does not contain a parameter named `{1}'",
5967 TypeManager.CSharpSignature (member), na.Name);
5969 } else if (args[name_index] != a && args[name_index] != null) {
5970 if (IsDelegateInvoke)
5971 ec.Report.SymbolRelatedToPreviousError (DelegateType);
5973 ec.Report.SymbolRelatedToPreviousError (member);
5975 ec.Report.Error (1744, na.Location,
5976 "Named argument `{0}' cannot be used for a parameter which has positional argument specified",
5981 if (a.Expr.Type.BuiltinType == BuiltinTypeSpec.Type.Dynamic)
5984 if ((restrictions & Restrictions.CovariantDelegate) != 0 && !Delegate.IsTypeCovariant (ec, a.Expr.Type, pt)) {
5985 if (a.IsExtensionType) {
5986 // TODO: Should report better message type, something similar to CS1928/1929 instead of
5987 // CS1061 but that still better than confusing CS0123
5988 var ma = new MemberAccess (a.Expr, member.Name, loc);
5989 ma.Error_TypeDoesNotContainDefinition (ec, a.Expr.Type, ma.Name);
5991 custom_errors.NoArgumentMatch (ec, member);
5997 if (a.IsExtensionType) {
5998 if (a.Expr.Type == pt || TypeSpecComparer.IsEqual (a.Expr.Type, pt)) {
6001 conv = Convert.ImplicitReferenceConversion (a.Expr, pt, false);
6003 conv = Convert.ImplicitBoxingConversion (a.Expr, a.Expr.Type, pt);
6006 conv = Convert.ImplicitConversion (ec, a.Expr, pt, loc);
6013 // Convert params arguments to an array initializer
6015 if (params_initializers != null) {
6016 // we choose to use 'a.Expr' rather than 'conv' so that
6017 // we don't hide the kind of expression we have (esp. CompoundAssign.Helper)
6018 params_initializers.Add (a.Expr);
6019 args.RemoveAt (a_idx--);
6025 // Update the argument with the implicit conversion
6029 if (a_idx != arg_count) {
6031 // Convert all var out argument to error type for less confusing error reporting
6032 // when no matching overload is found
6034 for (; a_idx < arg_count; a_idx++) {
6035 var arg = args [a_idx];
6039 if (arg.Type == InternalType.VarOutType) {
6040 ((DeclarationExpression)arg.Expr).Variable.Type = InternalType.ErrorType;
6044 ReportArgumentMismatch (ec, a_pos, member, a, pd, pt);
6049 // Fill not provided arguments required by params modifier
6051 if (params_initializers == null && arg_count + 1 == pd.Count) {
6053 args = new Arguments (1);
6055 pt = ptypes[pd.Count - 1];
6056 pt = TypeManager.GetElementType (pt);
6057 has_unsafe_arg |= pt.IsPointer;
6058 params_initializers = new ArrayInitializer (0, loc);
6062 // Append an array argument with all params arguments
6064 if (params_initializers != null) {
6065 args.Add (new Argument (
6066 new ArrayCreation (new TypeExpression (pt, loc), params_initializers, loc).Resolve (ec)));
6070 if (has_unsafe_arg && !ec.IsUnsafe) {
6071 Expression.UnsafeError (ec, loc);
6075 // We could infer inaccesible type arguments
6077 if (type_arguments == null && member.IsGeneric) {
6078 var ms = (MethodSpec) member;
6079 foreach (var ta in ms.TypeArguments) {
6080 if (!ta.IsAccessible (ec)) {
6081 ec.Report.SymbolRelatedToPreviousError (ta);
6082 Expression.ErrorIsInaccesible (ec, member.GetSignatureForError (), loc);
6092 public class ConstantExpr : MemberExpr
6094 readonly ConstSpec constant;
6096 public ConstantExpr (ConstSpec constant, Location loc)
6098 this.constant = constant;
6102 public override string Name {
6103 get { throw new NotImplementedException (); }
6106 public override string KindName {
6107 get { return "constant"; }
6110 public override bool IsInstance {
6111 get { return !IsStatic; }
6114 public override bool IsStatic {
6115 get { return true; }
6118 protected override TypeSpec DeclaringType {
6119 get { return constant.DeclaringType; }
6122 public override Expression CreateExpressionTree (ResolveContext ec)
6124 throw new NotSupportedException ("ET");
6127 protected override Expression DoResolve (ResolveContext rc)
6129 ResolveInstanceExpression (rc, null);
6130 DoBestMemberChecks (rc, constant);
6132 if (rc.HasSet (ResolveContext.Options.NameOfScope)) {
6133 eclass = ExprClass.Value;
6134 type = constant.MemberType;
6138 var c = constant.GetConstant (rc);
6140 // Creates reference expression to the constant value
6141 return Constant.CreateConstantFromValue (constant.MemberType, c.GetValue (), loc);
6144 public override void Emit (EmitContext ec)
6146 throw new NotSupportedException ();
6149 public override string GetSignatureForError ()
6151 return constant.GetSignatureForError ();
6154 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
6156 constant.CheckObsoleteness (rc, expr.Location);
6159 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
6161 Error_TypeArgumentsCannotBeUsed (ec, "constant", GetSignatureForError (), loc);
6166 // Fully resolved expression that references a Field
6168 public class FieldExpr : MemberExpr, IDynamicAssign, IMemoryLocation, IVariableReference
6170 protected FieldSpec spec;
6171 VariableInfo variable_info;
6173 LocalTemporary temp;
6176 protected FieldExpr (Location l)
6181 public FieldExpr (FieldSpec spec, Location loc)
6186 type = spec.MemberType;
6189 public FieldExpr (FieldBase fi, Location l)
6196 public override string Name {
6202 public bool IsHoisted {
6204 IVariableReference hv = InstanceExpression as IVariableReference;
6205 return hv != null && hv.IsHoisted;
6209 public override bool IsInstance {
6211 return !spec.IsStatic;
6215 public override bool IsStatic {
6217 return spec.IsStatic;
6221 public override string KindName {
6222 get { return "field"; }
6225 public FieldSpec Spec {
6231 protected override TypeSpec DeclaringType {
6233 return spec.DeclaringType;
6237 public VariableInfo VariableInfo {
6239 return variable_info;
6245 public override string GetSignatureForError ()
6247 return spec.GetSignatureForError ();
6250 public bool IsMarshalByRefAccess (ResolveContext rc)
6252 // Checks possible ldflda of field access expression
6253 return !spec.IsStatic && TypeSpec.IsValueType (spec.MemberType) && !(InstanceExpression is This) &&
6254 rc.Module.PredefinedTypes.MarshalByRefObject.Define () &&
6255 TypeSpec.IsBaseClass (spec.DeclaringType, rc.Module.PredefinedTypes.MarshalByRefObject.TypeSpec, false);
6258 public void SetHasAddressTaken ()
6260 IVariableReference vr = InstanceExpression as IVariableReference;
6262 vr.SetHasAddressTaken ();
6266 protected override void CloneTo (CloneContext clonectx, Expression target)
6268 var t = (FieldExpr) target;
6270 if (InstanceExpression != null)
6271 t.InstanceExpression = InstanceExpression.Clone (clonectx);
6274 public override Expression CreateExpressionTree (ResolveContext ec)
6276 if (ConditionalAccess) {
6277 Error_NullShortCircuitInsideExpressionTree (ec);
6280 return CreateExpressionTree (ec, true);
6283 public Expression CreateExpressionTree (ResolveContext ec, bool convertInstance)
6286 Expression instance;
6288 if (InstanceExpression == null) {
6289 instance = new NullLiteral (loc);
6290 } else if (convertInstance) {
6291 instance = InstanceExpression.CreateExpressionTree (ec);
6293 args = new Arguments (1);
6294 args.Add (new Argument (InstanceExpression));
6295 instance = CreateExpressionFactoryCall (ec, "Constant", args);
6298 args = Arguments.CreateForExpressionTree (ec, null,
6300 CreateTypeOfExpression ());
6302 return CreateExpressionFactoryCall (ec, "Field", args);
6305 public Expression CreateTypeOfExpression ()
6307 return new TypeOfField (spec, loc);
6310 protected override Expression DoResolve (ResolveContext ec)
6312 spec.MemberDefinition.SetIsUsed ();
6314 return DoResolve (ec, null);
6317 Expression DoResolve (ResolveContext ec, Expression rhs)
6319 bool lvalue_instance = rhs != null && IsInstance && spec.DeclaringType.IsStruct;
6322 ResolveConditionalAccessReceiver (ec);
6324 if (ResolveInstanceExpression (ec, rhs)) {
6325 // Resolve the field's instance expression while flow analysis is turned
6326 // off: when accessing a field "a.b", we must check whether the field
6327 // "a.b" is initialized, not whether the whole struct "a" is initialized.
6329 if (lvalue_instance) {
6330 bool out_access = rhs == EmptyExpression.OutAccess || rhs == EmptyExpression.LValueMemberOutAccess;
6332 Expression right_side =
6333 out_access ? EmptyExpression.LValueMemberOutAccess : EmptyExpression.LValueMemberAccess;
6335 InstanceExpression = InstanceExpression.ResolveLValue (ec, right_side);
6337 InstanceExpression = InstanceExpression.Resolve (ec, ResolveFlags.VariableOrValue);
6340 if (InstanceExpression == null)
6344 DoBestMemberChecks (ec, spec);
6346 if (conditional_access_receiver)
6347 ec.With (ResolveContext.Options.DontSetConditionalAccessReceiver, false);
6350 var fb = spec as FixedFieldSpec;
6351 IVariableReference var = InstanceExpression as IVariableReference;
6354 IFixedExpression fe = InstanceExpression as IFixedExpression;
6355 if (!ec.HasSet (ResolveContext.Options.FixedInitializerScope) && (fe == null || !fe.IsFixed)) {
6356 ec.Report.Error (1666, loc, "You cannot use fixed size buffers contained in unfixed expressions. Try using the fixed statement");
6359 if (InstanceExpression.eclass != ExprClass.Variable) {
6360 ec.Report.SymbolRelatedToPreviousError (spec);
6361 ec.Report.Error (1708, loc, "`{0}': Fixed size buffers can only be accessed through locals or fields",
6362 TypeManager.GetFullNameSignature (spec));
6363 } else if (var != null && var.IsHoisted) {
6364 AnonymousMethodExpression.Error_AddressOfCapturedVar (ec, var, loc);
6367 return new FixedBufferPtr (this, fb.ElementType, loc).Resolve (ec);
6371 // Set flow-analysis variable info for struct member access. It will be check later
6372 // for precise error reporting
6374 if (var != null && var.VariableInfo != null && InstanceExpression.Type.IsStruct) {
6375 variable_info = var.VariableInfo.GetStructFieldInfo (Name);
6378 if (conditional_access_receiver)
6379 type = LiftMemberType (ec, type);
6381 if (ConditionalAccess && InstanceExpression != null && InstanceExpression.IsNull)
6382 return Constant.CreateConstantFromValue (type, null, loc);
6384 eclass = ExprClass.Variable;
6388 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
6390 spec.CheckObsoleteness (rc, expr.Location);
6393 public void SetFieldAssigned (FlowAnalysisContext fc)
6398 bool lvalue_instance = spec.DeclaringType.IsStruct;
6399 if (lvalue_instance) {
6400 var var = InstanceExpression as IVariableReference;
6401 if (var != null && var.VariableInfo != null) {
6402 fc.SetStructFieldAssigned (var.VariableInfo, Name);
6406 var fe = InstanceExpression as FieldExpr;
6408 Expression instance;
6411 instance = fe.InstanceExpression;
6412 var fe_instance = instance as FieldExpr;
6413 if ((fe_instance != null && !fe_instance.IsStatic) || instance is LocalVariableReference) {
6414 if (TypeSpec.IsReferenceType (fe.Type) && instance.Type.IsStruct) {
6415 var var = InstanceExpression as IVariableReference;
6416 if (var != null && var.VariableInfo == null) {
6417 var var_inst = instance as IVariableReference;
6418 if (var_inst == null || (var_inst.VariableInfo != null && !fc.IsDefinitelyAssigned (var_inst.VariableInfo)))
6419 fc.Report.Warning (1060, 1, fe.loc, "Use of possibly unassigned field `{0}'", fe.Name);
6423 if (fe_instance != null) {
6432 if (instance != null && TypeSpec.IsReferenceType (instance.Type))
6433 instance.FlowAnalysis (fc);
6435 if (TypeSpec.IsReferenceType (InstanceExpression.Type))
6436 InstanceExpression.FlowAnalysis (fc);
6440 Expression Error_AssignToReadonly (ResolveContext rc, Expression right_side)
6442 // The return value is always null. Returning a value simplifies calling code.
6444 if (right_side == EmptyExpression.OutAccess) {
6446 rc.Report.Error (199, loc, "A static readonly field `{0}' cannot be passed ref or out (except in a static constructor)",
6447 GetSignatureForError ());
6449 rc.Report.Error (192, loc, "A readonly field `{0}' cannot be passed ref or out (except in a constructor)",
6450 GetSignatureForError ());
6456 if (right_side == EmptyExpression.LValueMemberAccess) {
6457 // Already reported as CS1648/CS1650
6461 if (right_side == EmptyExpression.LValueMemberOutAccess) {
6463 rc.Report.Error (1651, loc, "Fields of static readonly field `{0}' cannot be passed ref or out (except in a static constructor)",
6464 GetSignatureForError ());
6466 rc.Report.Error (1649, loc, "Members of readonly field `{0}' cannot be passed ref or out (except in a constructor)",
6467 GetSignatureForError ());
6473 rc.Report.Error (198, loc, "A static readonly field `{0}' cannot be assigned to (except in a static constructor or a variable initializer)",
6474 GetSignatureForError ());
6476 rc.Report.Error (191, loc, "A readonly field `{0}' cannot be assigned to (except in a constructor or a variable initializer)",
6477 GetSignatureForError ());
6483 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
6485 if (HasConditionalAccess ())
6486 Error_NullPropagatingLValue (ec);
6488 if (spec is FixedFieldSpec) {
6489 // It could be much better error message but we want to be error compatible
6490 Error_ValueAssignment (ec, right_side);
6493 Expression e = DoResolve (ec, right_side);
6498 spec.MemberDefinition.SetIsAssigned ();
6500 if ((right_side == EmptyExpression.UnaryAddress || right_side == EmptyExpression.OutAccess) &&
6501 (spec.Modifiers & Modifiers.VOLATILE) != 0) {
6502 ec.Report.Warning (420, 1, loc,
6503 "`{0}': A volatile field references will not be treated as volatile",
6504 spec.GetSignatureForError ());
6507 if (spec.IsReadOnly) {
6508 // InitOnly fields can only be assigned in constructors or initializers
6509 if (!ec.HasAny (ResolveContext.Options.FieldInitializerScope | ResolveContext.Options.ConstructorScope))
6510 return Error_AssignToReadonly (ec, right_side);
6512 if (ec.HasSet (ResolveContext.Options.ConstructorScope)) {
6514 // InitOnly fields cannot be assigned-to in a different constructor from their declaring type
6515 if (ec.CurrentMemberDefinition.Parent.PartialContainer.Definition != spec.DeclaringType.GetDefinition ())
6516 return Error_AssignToReadonly (ec, right_side);
6517 // static InitOnly fields cannot be assigned-to in an instance constructor
6518 if (IsStatic && !ec.IsStatic)
6519 return Error_AssignToReadonly (ec, right_side);
6520 // instance constructors can't modify InitOnly fields of other instances of the same type
6521 if (!IsStatic && !(InstanceExpression is This))
6522 return Error_AssignToReadonly (ec, right_side);
6526 if (right_side == EmptyExpression.OutAccess && IsMarshalByRefAccess (ec)) {
6527 ec.Report.SymbolRelatedToPreviousError (spec.DeclaringType);
6528 ec.Report.Warning (197, 1, loc,
6529 "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",
6530 GetSignatureForError ());
6533 eclass = ExprClass.Variable;
6537 public override void FlowAnalysis (FlowAnalysisContext fc)
6539 var var = InstanceExpression as IVariableReference;
6541 var vi = var.VariableInfo;
6542 if (vi != null && !fc.IsStructFieldDefinitelyAssigned (vi, Name)) {
6543 fc.Report.Error (170, loc, "Use of possibly unassigned field `{0}'", Name);
6547 if (TypeSpec.IsValueType (InstanceExpression.Type)) {
6548 var le = SkipLeftValueTypeAccess (InstanceExpression);
6550 le.FlowAnalysis (fc);
6556 var da = conditional_access_receiver ? fc.BranchDefiniteAssignment () : null;
6558 base.FlowAnalysis (fc);
6560 if (conditional_access_receiver)
6561 fc.DefiniteAssignment = da;
6564 static Expression SkipLeftValueTypeAccess (Expression expr)
6566 if (!TypeSpec.IsValueType (expr.Type))
6569 if (expr is VariableReference)
6572 var fe = expr as FieldExpr;
6576 if (fe.InstanceExpression == null)
6579 return SkipLeftValueTypeAccess (fe.InstanceExpression);
6582 public override int GetHashCode ()
6584 return spec.GetHashCode ();
6587 public bool IsFixed {
6590 // A variable of the form V.I is fixed when V is a fixed variable of a struct type
6592 IVariableReference variable = InstanceExpression as IVariableReference;
6593 if (variable != null)
6594 return InstanceExpression.Type.IsStruct && variable.IsFixed;
6596 IFixedExpression fe = InstanceExpression as IFixedExpression;
6597 return fe != null && fe.IsFixed;
6601 public override bool Equals (object obj)
6603 FieldExpr fe = obj as FieldExpr;
6607 if (spec != fe.spec)
6610 if (InstanceExpression == null || fe.InstanceExpression == null)
6613 return InstanceExpression.Equals (fe.InstanceExpression);
6616 public void Emit (EmitContext ec, bool leave_copy)
6618 bool is_volatile = (spec.Modifiers & Modifiers.VOLATILE) != 0;
6622 ec.Emit (OpCodes.Volatile);
6624 ec.Emit (OpCodes.Ldsfld, spec);
6626 var ca = ec.ConditionalAccess;
6629 if (conditional_access_receiver)
6630 ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
6632 EmitInstance (ec, false);
6635 // Optimization for build-in types
6636 if (type.IsStruct && type == ec.CurrentType && InstanceExpression.Type == type) {
6637 ec.EmitLoadFromPtr (type);
6639 var ff = spec as FixedFieldSpec;
6641 ec.Emit (OpCodes.Ldflda, spec);
6642 ec.Emit (OpCodes.Ldflda, ff.Element);
6645 ec.Emit (OpCodes.Volatile);
6647 ec.Emit (OpCodes.Ldfld, spec);
6651 if (conditional_access_receiver) {
6652 ec.CloseConditionalAccess (type.IsNullableType && type != spec.MemberType ? type : null);
6653 ec.ConditionalAccess = ca;
6658 ec.Emit (OpCodes.Dup);
6660 temp = new LocalTemporary (this.Type);
6666 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
6668 bool has_await_source = ec.HasSet (BuilderContext.Options.AsyncBody) && source.ContainsEmitWithAwait ();
6669 if (isCompound && !(source is DynamicExpressionStatement) && !has_await_source) {
6674 if (ConditionalAccess)
6675 throw new NotImplementedException ("null operator assignment");
6677 if (has_await_source)
6678 source = source.EmitToField (ec);
6680 EmitInstance (ec, prepared);
6685 if (leave_copy || ec.NotifyEvaluatorOnStore) {
6686 ec.Emit (OpCodes.Dup);
6688 temp = new LocalTemporary (this.Type);
6693 if ((spec.Modifiers & Modifiers.VOLATILE) != 0)
6694 ec.Emit (OpCodes.Volatile);
6696 spec.MemberDefinition.SetIsAssigned ();
6699 ec.Emit (OpCodes.Stsfld, spec);
6701 ec.Emit (OpCodes.Stfld, spec);
6703 if (ec.NotifyEvaluatorOnStore) {
6705 throw new NotImplementedException ("instance field write");
6708 ec.Emit (OpCodes.Dup);
6710 ec.Module.Evaluator.EmitValueChangedCallback (ec, Name, type, loc);
6721 // Emits store to field with prepared values on stack
6723 public void EmitAssignFromStack (EmitContext ec)
6726 ec.Emit (OpCodes.Stsfld, spec);
6728 ec.Emit (OpCodes.Stfld, spec);
6732 public override void Emit (EmitContext ec)
6737 public override void EmitSideEffect (EmitContext ec)
6739 bool is_volatile = (spec.Modifiers & Modifiers.VOLATILE) != 0;
6741 if (is_volatile) // || is_marshal_by_ref ())
6742 base.EmitSideEffect (ec);
6745 public virtual void AddressOf (EmitContext ec, AddressOp mode)
6747 if ((mode & AddressOp.Store) != 0)
6748 spec.MemberDefinition.SetIsAssigned ();
6749 if ((mode & AddressOp.Load) != 0)
6750 spec.MemberDefinition.SetIsUsed ();
6753 // Handle initonly fields specially: make a copy and then
6754 // get the address of the copy.
6757 if (spec.IsReadOnly){
6759 if (ec.HasSet (EmitContext.Options.ConstructorScope) && spec.DeclaringType == ec.CurrentType) {
6771 var temp = ec.GetTemporaryLocal (type);
6772 ec.Emit (OpCodes.Stloc, temp);
6773 ec.Emit (OpCodes.Ldloca, temp);
6779 ec.Emit (OpCodes.Ldsflda, spec);
6782 EmitInstance (ec, false);
6783 ec.Emit (OpCodes.Ldflda, spec);
6787 public SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source)
6789 return MakeExpression (ctx);
6792 public override SLE.Expression MakeExpression (BuilderContext ctx)
6795 return base.MakeExpression (ctx);
6797 return SLE.Expression.Field (
6798 IsStatic ? null : InstanceExpression.MakeExpression (ctx),
6799 spec.GetMetaInfo ());
6803 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
6805 Error_TypeArgumentsCannotBeUsed (ec, "field", GetSignatureForError (), loc);
6811 // Expression that evaluates to a Property.
6813 // This is not an LValue because we need to re-write the expression. We
6814 // can not take data from the stack and store it.
6816 sealed class PropertyExpr : PropertyOrIndexerExpr<PropertySpec>
6818 Arguments arguments;
6819 FieldExpr backing_field;
6821 public PropertyExpr (PropertySpec spec, Location l)
6824 best_candidate = spec;
6825 type = spec.MemberType;
6830 protected override Arguments Arguments {
6839 protected override TypeSpec DeclaringType {
6841 return best_candidate.DeclaringType;
6845 public override string Name {
6847 return best_candidate.Name;
6851 public bool IsAutoPropertyAccess {
6853 var prop = best_candidate.MemberDefinition as Property;
6854 return prop != null && prop.BackingField != null;
6858 public override bool IsInstance {
6864 public override bool IsStatic {
6866 return best_candidate.IsStatic;
6870 public override string KindName {
6871 get { return "property"; }
6874 public PropertySpec PropertyInfo {
6876 return best_candidate;
6882 public override MethodGroupExpr CanReduceLambda (AnonymousMethodBody body)
6884 if (best_candidate == null || !(best_candidate.IsStatic || InstanceExpression is This))
6887 var args_count = arguments == null ? 0 : arguments.Count;
6888 if (args_count != body.Parameters.Count && args_count == 0)
6891 var mg = MethodGroupExpr.CreatePredefined (best_candidate.Get, DeclaringType, loc);
6892 mg.InstanceExpression = InstanceExpression;
6897 public static PropertyExpr CreatePredefined (PropertySpec spec, Location loc)
6899 return new PropertyExpr (spec, loc) {
6905 public override Expression CreateExpressionTree (ResolveContext ec)
6907 if (ConditionalAccess) {
6908 Error_NullShortCircuitInsideExpressionTree (ec);
6912 if (IsSingleDimensionalArrayLength ()) {
6913 args = new Arguments (1);
6914 args.Add (new Argument (InstanceExpression.CreateExpressionTree (ec)));
6915 return CreateExpressionFactoryCall (ec, "ArrayLength", args);
6918 args = new Arguments (2);
6919 if (InstanceExpression == null)
6920 args.Add (new Argument (new NullLiteral (loc)));
6922 args.Add (new Argument (InstanceExpression.CreateExpressionTree (ec)));
6923 args.Add (new Argument (new TypeOfMethod (Getter, loc)));
6924 return CreateExpressionFactoryCall (ec, "Property", args);
6927 public Expression CreateSetterTypeOfExpression (ResolveContext rc)
6929 DoResolveLValue (rc, null);
6930 return new TypeOfMethod (Setter, loc);
6933 public override string GetSignatureForError ()
6935 return best_candidate.GetSignatureForError ();
6938 public override SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source)
6941 return base.MakeExpression (ctx);
6943 return SLE.Expression.Property (InstanceExpression.MakeExpression (ctx), (MethodInfo) Setter.GetMetaInfo ());
6947 public override SLE.Expression MakeExpression (BuilderContext ctx)
6950 return base.MakeExpression (ctx);
6952 return SLE.Expression.Property (InstanceExpression.MakeExpression (ctx), (MethodInfo) Getter.GetMetaInfo ());
6956 void Error_PropertyNotValid (ResolveContext ec)
6958 ec.Report.SymbolRelatedToPreviousError (best_candidate);
6959 ec.Report.Error (1546, loc, "Property or event `{0}' is not supported by the C# language",
6960 GetSignatureForError ());
6963 bool IsSingleDimensionalArrayLength ()
6965 if (best_candidate.DeclaringType.BuiltinType != BuiltinTypeSpec.Type.Array || !best_candidate.HasGet || Name != "Length")
6968 ArrayContainer ac = InstanceExpression.Type as ArrayContainer;
6969 return ac != null && ac.Rank == 1;
6972 public override void Emit (EmitContext ec, bool leave_copy)
6975 // Special case: length of single dimension array property is turned into ldlen
6977 if (IsSingleDimensionalArrayLength ()) {
6978 if (conditional_access_receiver) {
6979 ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
6982 EmitInstance (ec, false);
6984 ec.Emit (OpCodes.Ldlen);
6985 ec.Emit (OpCodes.Conv_I4);
6987 if (conditional_access_receiver) {
6988 ec.CloseConditionalAccess (type);
6994 base.Emit (ec, leave_copy);
6997 public override void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
6999 if (backing_field != null) {
7000 backing_field.EmitAssign (ec, source, false, false);
7005 LocalTemporary await_source_arg = null;
7007 if (isCompound && !(source is DynamicExpressionStatement)) {
7008 emitting_compound_assignment = true;
7011 if (has_await_arguments) {
7012 await_source_arg = new LocalTemporary (Type);
7013 await_source_arg.Store (ec);
7015 args = new Arguments (1);
7016 args.Add (new Argument (await_source_arg));
7019 temp = await_source_arg;
7022 has_await_arguments = false;
7027 ec.Emit (OpCodes.Dup);
7028 temp = new LocalTemporary (this.Type);
7033 args = arguments ?? new Arguments (1);
7037 temp = new LocalTemporary (this.Type);
7039 args.Add (new Argument (temp));
7041 args.Add (new Argument (source));
7045 emitting_compound_assignment = false;
7047 var call = new CallEmitter ();
7048 call.InstanceExpression = InstanceExpression;
7050 call.InstanceExpressionOnStack = true;
7052 if (ConditionalAccess) {
7053 call.ConditionalAccess = true;
7057 call.Emit (ec, Setter, args, loc);
7059 call.EmitStatement (ec, Setter, args, loc);
7066 if (await_source_arg != null) {
7067 await_source_arg.Release (ec);
7071 public override void FlowAnalysis (FlowAnalysisContext fc)
7073 var prop = best_candidate.MemberDefinition as Property;
7074 if (prop != null && prop.BackingField != null) {
7075 var var = InstanceExpression as IVariableReference;
7077 var vi = var.VariableInfo;
7078 if (vi != null && !fc.IsStructFieldDefinitelyAssigned (vi, prop.BackingField.Name)) {
7079 fc.Report.Error (8079, loc, "Use of possibly unassigned auto-implemented property `{0}'", Name);
7083 if (TypeSpec.IsValueType (InstanceExpression.Type) && InstanceExpression is VariableReference)
7088 var da = conditional_access_receiver ? fc.BranchDefiniteAssignment () : null;
7090 base.FlowAnalysis (fc);
7092 if (conditional_access_receiver)
7093 fc.DefiniteAssignment = da;
7096 protected override Expression OverloadResolve (ResolveContext rc, Expression right_side)
7098 eclass = ExprClass.PropertyAccess;
7100 if (best_candidate.IsNotCSharpCompatible) {
7101 Error_PropertyNotValid (rc);
7104 ResolveInstanceExpression (rc, right_side);
7106 if ((best_candidate.Modifiers & (Modifiers.ABSTRACT | Modifiers.VIRTUAL)) != 0 && best_candidate.DeclaringType != InstanceExpression.Type) {
7107 var filter = new MemberFilter (best_candidate.Name, 0, MemberKind.Property, null, null);
7108 var p = MemberCache.FindMember (InstanceExpression.Type, filter, BindingRestriction.InstanceOnly | BindingRestriction.OverrideOnly) as PropertySpec;
7110 type = p.MemberType;
7114 DoBestMemberChecks (rc, best_candidate);
7116 // Handling of com-imported properties with any number of default property parameters
7117 if (best_candidate.HasGet && !best_candidate.Get.Parameters.IsEmpty) {
7118 var p = best_candidate.Get.Parameters;
7119 arguments = new Arguments (p.Count);
7120 for (int i = 0; i < p.Count; ++i) {
7121 arguments.Add (new Argument (OverloadResolver.ResolveDefaultValueArgument (rc, p.Types [i], p.FixedParameters [i].DefaultValue, loc)));
7123 } else if (best_candidate.HasSet && best_candidate.Set.Parameters.Count > 1) {
7124 var p = best_candidate.Set.Parameters;
7125 arguments = new Arguments (p.Count - 1);
7126 for (int i = 0; i < p.Count - 1; ++i) {
7127 arguments.Add (new Argument (OverloadResolver.ResolveDefaultValueArgument (rc, p.Types [i], p.FixedParameters [i].DefaultValue, loc)));
7134 protected override bool ResolveAutopropertyAssignment (ResolveContext rc, Expression rhs)
7136 if (!rc.HasSet (ResolveContext.Options.ConstructorScope))
7139 var prop = best_candidate.MemberDefinition as Property;
7140 if (prop == null || prop.Parent.PartialContainer != rc.CurrentMemberDefinition.Parent.PartialContainer) {
7141 var ps = MemberCache.FindMember (rc.CurrentType, MemberFilter.Property (best_candidate.Name, best_candidate.MemberType), BindingRestriction.DeclaredOnly) as PropertySpec;
7145 prop = (Property)ps.MemberDefinition;
7148 var spec = prop.BackingField;
7152 if (rc.IsStatic != spec.IsStatic)
7155 if (!spec.IsStatic && (!(InstanceExpression is This) || InstanceExpression is BaseThis))
7158 backing_field = new FieldExpr (prop.BackingField, loc);
7159 backing_field.ResolveLValue (rc, rhs);
7163 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
7165 if (!best_candidate.IsAccessible (rc))
7166 ErrorIsInaccesible (rc, best_candidate.GetSignatureForError (), expr.Location);
7168 best_candidate.CheckObsoleteness (rc, expr.Location);
7171 public void SetBackingFieldAssigned (FlowAnalysisContext fc)
7173 if (backing_field != null) {
7174 backing_field.SetFieldAssigned (fc);
7178 if (!IsAutoPropertyAccess)
7181 var prop = best_candidate.MemberDefinition as Property;
7182 if (prop != null && prop.BackingField != null) {
7183 bool lvalue_instance = best_candidate.DeclaringType.IsStruct;
7184 if (lvalue_instance) {
7185 var var = InstanceExpression as IVariableReference;
7186 if (var != null && var.VariableInfo != null) {
7187 fc.SetStructFieldAssigned (var.VariableInfo, prop.BackingField.Name);
7193 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
7195 Error_TypeArgumentsCannotBeUsed (ec, "property", GetSignatureForError (), loc);
7199 abstract class PropertyOrIndexerExpr<T> : MemberExpr, IDynamicAssign where T : PropertySpec
7201 // getter and setter can be different for base calls
7202 MethodSpec getter, setter;
7203 protected T best_candidate;
7205 protected LocalTemporary temp;
7206 protected bool emitting_compound_assignment;
7207 protected bool has_await_arguments;
7209 protected PropertyOrIndexerExpr (Location l)
7216 protected abstract Arguments Arguments { get; set; }
7218 public MethodSpec Getter {
7227 public MethodSpec Setter {
7238 protected override Expression DoResolve (ResolveContext ec)
7240 if (eclass == ExprClass.Unresolved) {
7241 ResolveConditionalAccessReceiver (ec);
7243 var expr = OverloadResolve (ec, null);
7248 using (ec.With (ResolveContext.Options.DontSetConditionalAccessReceiver, conditional_access_receiver))
7249 return expr.Resolve (ec);
7252 if (conditional_access_receiver) {
7253 type = LiftMemberType (ec, type);
7257 if (!ResolveGetter (ec))
7263 public override Expression DoResolveLValue (ResolveContext rc, Expression right_side)
7265 if (HasConditionalAccess ())
7266 Error_NullPropagatingLValue (rc);
7268 if (right_side == EmptyExpression.OutAccess) {
7269 // TODO: best_candidate can be null at this point
7270 INamedBlockVariable variable = null;
7271 if (best_candidate != null && rc.CurrentBlock.ParametersBlock.TopBlock.GetLocalName (best_candidate.Name, rc.CurrentBlock, ref variable) && variable is Linq.RangeVariable) {
7272 rc.Report.Error (1939, loc, "A range variable `{0}' may not be passes as `ref' or `out' parameter",
7273 best_candidate.Name);
7275 right_side.DoResolveLValue (rc, this);
7280 if (eclass == ExprClass.Unresolved) {
7281 var expr = OverloadResolve (rc, right_side);
7286 return expr.ResolveLValue (rc, right_side);
7288 ResolveInstanceExpression (rc, right_side);
7291 if (!best_candidate.HasSet) {
7292 if (ResolveAutopropertyAssignment (rc, right_side))
7295 rc.Report.Error (200, loc, "Property or indexer `{0}' cannot be assigned to (it is read-only)",
7296 GetSignatureForError ());
7300 if (!best_candidate.Set.IsAccessible (rc) || !best_candidate.Set.DeclaringType.IsAccessible (rc)) {
7301 if (best_candidate.HasDifferentAccessibility) {
7302 rc.Report.SymbolRelatedToPreviousError (best_candidate.Set);
7303 rc.Report.Error (272, loc, "The property or indexer `{0}' cannot be used in this context because the set accessor is inaccessible",
7304 GetSignatureForError ());
7306 rc.Report.SymbolRelatedToPreviousError (best_candidate.Set);
7307 ErrorIsInaccesible (rc, best_candidate.GetSignatureForError (), loc);
7311 if (best_candidate.HasDifferentAccessibility)
7312 CheckProtectedMemberAccess (rc, best_candidate.Set);
7314 setter = CandidateToBaseOverride (rc, best_candidate.Set);
7318 void EmitConditionalAccess (EmitContext ec, ref CallEmitter call, MethodSpec method, Arguments arguments)
7320 var ca = ec.ConditionalAccess;
7321 ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
7323 call.Emit (ec, method, arguments, loc);
7325 ec.CloseConditionalAccess (method.ReturnType != type && type.IsNullableType ? type : null);
7326 ec.ConditionalAccess = ca;
7330 // Implements the IAssignMethod interface for assignments
7332 public virtual void Emit (EmitContext ec, bool leave_copy)
7334 var call = new CallEmitter ();
7335 call.ConditionalAccess = ConditionalAccess;
7336 call.InstanceExpression = InstanceExpression;
7337 if (has_await_arguments)
7338 call.HasAwaitArguments = true;
7340 call.DuplicateArguments = emitting_compound_assignment;
7342 if (conditional_access_receiver)
7343 EmitConditionalAccess (ec, ref call, Getter, Arguments);
7345 call.Emit (ec, Getter, Arguments, loc);
7347 if (call.HasAwaitArguments) {
7348 InstanceExpression = call.InstanceExpression;
7349 Arguments = call.EmittedArguments;
7350 has_await_arguments = true;
7354 ec.Emit (OpCodes.Dup);
7355 temp = new LocalTemporary (Type);
7360 public abstract void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound);
7362 public override void Emit (EmitContext ec)
7367 protected override FieldExpr EmitToFieldSource (EmitContext ec)
7369 has_await_arguments = true;
7374 public abstract SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source);
7376 protected abstract Expression OverloadResolve (ResolveContext rc, Expression right_side);
7378 bool ResolveGetter (ResolveContext rc)
7380 if (!best_candidate.HasGet) {
7381 if (InstanceExpression != EmptyExpression.Null) {
7382 rc.Report.SymbolRelatedToPreviousError (best_candidate);
7383 rc.Report.Error (154, loc, "The property or indexer `{0}' cannot be used in this context because it lacks the `get' accessor",
7384 best_candidate.GetSignatureForError ());
7387 } else if (!best_candidate.Get.IsAccessible (rc) || !best_candidate.Get.DeclaringType.IsAccessible (rc)) {
7388 if (best_candidate.HasDifferentAccessibility) {
7389 rc.Report.SymbolRelatedToPreviousError (best_candidate.Get);
7390 rc.Report.Error (271, loc, "The property or indexer `{0}' cannot be used in this context because the get accessor is inaccessible",
7391 TypeManager.CSharpSignature (best_candidate));
7393 rc.Report.SymbolRelatedToPreviousError (best_candidate.Get);
7394 ErrorIsInaccesible (rc, best_candidate.Get.GetSignatureForError (), loc);
7398 if (best_candidate.HasDifferentAccessibility) {
7399 CheckProtectedMemberAccess (rc, best_candidate.Get);
7402 getter = CandidateToBaseOverride (rc, best_candidate.Get);
7406 protected virtual bool ResolveAutopropertyAssignment (ResolveContext rc, Expression rhs)
7413 /// Fully resolved expression that evaluates to an Event
7415 public class EventExpr : MemberExpr, IAssignMethod
7417 readonly EventSpec spec;
7420 public EventExpr (EventSpec spec, Location loc)
7428 protected override TypeSpec DeclaringType {
7430 return spec.DeclaringType;
7434 public override string Name {
7440 public override bool IsInstance {
7442 return !spec.IsStatic;
7446 public override bool IsStatic {
7448 return spec.IsStatic;
7452 public override string KindName {
7453 get { return "event"; }
7456 public MethodSpec Operator {
7464 public override MemberExpr ResolveMemberAccess (ResolveContext ec, Expression left, SimpleName original)
7467 // If the event is local to this class and we are not lhs of +=/-= we transform ourselves into a FieldExpr
7469 if (!ec.HasSet (ResolveContext.Options.CompoundAssignmentScope)) {
7470 if (spec.BackingField != null &&
7471 (spec.DeclaringType == ec.CurrentType || TypeManager.IsNestedChildOf (ec.CurrentType, spec.DeclaringType.MemberDefinition))) {
7473 spec.MemberDefinition.SetIsUsed ();
7475 spec.CheckObsoleteness (ec, loc);
7477 if ((spec.Modifiers & (Modifiers.ABSTRACT | Modifiers.EXTERN)) != 0)
7478 Error_AssignmentEventOnly (ec);
7480 FieldExpr ml = new FieldExpr (spec.BackingField, loc);
7482 InstanceExpression = null;
7484 return ml.ResolveMemberAccess (ec, left, original);
7488 return base.ResolveMemberAccess (ec, left, original);
7491 public override Expression CreateExpressionTree (ResolveContext ec)
7493 throw new NotSupportedException ("ET");
7496 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
7498 if (right_side == EmptyExpression.EventAddition) {
7499 op = spec.AccessorAdd;
7500 } else if (right_side == EmptyExpression.EventSubtraction) {
7501 op = spec.AccessorRemove;
7505 Error_AssignmentEventOnly (ec);
7509 if (HasConditionalAccess ())
7510 Error_NullPropagatingLValue (ec);
7512 op = CandidateToBaseOverride (ec, op);
7516 protected override Expression DoResolve (ResolveContext ec)
7518 eclass = ExprClass.EventAccess;
7519 type = spec.MemberType;
7521 ResolveInstanceExpression (ec, null);
7523 if (!ec.HasSet (ResolveContext.Options.CompoundAssignmentScope)) {
7524 Error_AssignmentEventOnly (ec);
7527 DoBestMemberChecks (ec, spec);
7531 public override void Emit (EmitContext ec)
7533 throw new NotSupportedException ();
7534 //Error_CannotAssign ();
7537 #region IAssignMethod Members
7539 public void Emit (EmitContext ec, bool leave_copy)
7541 throw new NotImplementedException ();
7544 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
7546 if (leave_copy || !isCompound)
7547 throw new NotImplementedException ("EventExpr::EmitAssign");
7549 Arguments args = new Arguments (1);
7550 args.Add (new Argument (source));
7552 // TODO: Wrong, needs receiver
7553 // if (NullShortCircuit) {
7554 // ec.ConditionalAccess = new ConditionalAccessContext (type, ec.DefineLabel ());
7557 var call = new CallEmitter ();
7558 call.InstanceExpression = InstanceExpression;
7559 call.ConditionalAccess = ConditionalAccess;
7560 call.EmitStatement (ec, op, args, loc);
7562 // if (NullShortCircuit)
7563 // ec.CloseConditionalAccess (null);
7568 void Error_AssignmentEventOnly (ResolveContext ec)
7570 if (spec.DeclaringType == ec.CurrentType || TypeManager.IsNestedChildOf (ec.CurrentType, spec.DeclaringType.MemberDefinition)) {
7571 ec.Report.Error (79, loc,
7572 "The event `{0}' can only appear on the left hand side of `+=' or `-=' operator",
7573 GetSignatureForError ());
7575 ec.Report.Error (70, loc,
7576 "The event `{0}' can only appear on the left hand side of += or -= when used outside of the type `{1}'",
7577 GetSignatureForError (), spec.DeclaringType.GetSignatureForError ());
7581 protected override void Error_CannotCallAbstractBase (ResolveContext rc, string name)
7583 name = name.Substring (0, name.LastIndexOf ('.'));
7584 base.Error_CannotCallAbstractBase (rc, name);
7587 public override string GetSignatureForError ()
7589 return TypeManager.CSharpSignature (spec);
7592 public override void ResolveNameOf (ResolveContext rc, ATypeNameExpression expr)
7594 spec.CheckObsoleteness (rc, expr.Location);
7597 public override void SetTypeArguments (ResolveContext ec, TypeArguments ta)
7599 Error_TypeArgumentsCannotBeUsed (ec, "event", GetSignatureForError (), loc);
7603 public class TemporaryVariableReference : VariableReference
7605 public class Declarator : Statement
7607 TemporaryVariableReference variable;
7609 public Declarator (TemporaryVariableReference variable)
7611 this.variable = variable;
7615 protected override void DoEmit (EmitContext ec)
7617 variable.li.CreateBuilder (ec);
7620 public override void Emit (EmitContext ec)
7622 // Don't create sequence point
7626 protected override bool DoFlowAnalysis (FlowAnalysisContext fc)
7631 protected override void CloneTo (CloneContext clonectx, Statement target)
7639 public TemporaryVariableReference (LocalVariable li, Location loc)
7642 this.type = li.Type;
7646 public override bool IsLockedByStatement {
7654 public LocalVariable LocalInfo {
7660 public static TemporaryVariableReference Create (TypeSpec type, Block block, Location loc, bool writeToSymbolFile = false)
7662 var li = LocalVariable.CreateCompilerGenerated (type, block, loc, writeToSymbolFile);
7663 return new TemporaryVariableReference (li, loc);
7666 protected override Expression DoResolve (ResolveContext ec)
7668 eclass = ExprClass.Variable;
7671 // Don't capture temporary variables except when using
7672 // state machine redirection and block yields
7674 if (ec.CurrentAnonymousMethod is StateMachineInitializer &&
7675 (ec.CurrentBlock.Explicit.HasYield || ec.CurrentBlock.Explicit.HasAwait) &&
7676 ec.IsVariableCapturingRequired) {
7677 AnonymousMethodStorey storey = li.Block.Explicit.CreateAnonymousMethodStorey (ec);
7678 storey.CaptureLocalVariable (ec, li);
7684 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
7686 return Resolve (ec);
7689 public override void Emit (EmitContext ec)
7691 li.CreateBuilder (ec);
7696 public void EmitAssign (EmitContext ec, Expression source)
7698 li.CreateBuilder (ec);
7700 EmitAssign (ec, source, false, false);
7703 public override HoistedVariable GetHoistedVariable (AnonymousExpression ae)
7705 return li.HoistedVariant;
7708 public override bool IsFixed {
7709 get { return true; }
7712 public override bool IsRef {
7713 get { return false; }
7716 public override string Name {
7717 get { throw new NotImplementedException (); }
7720 public override void SetHasAddressTaken ()
7722 throw new NotImplementedException ();
7725 protected override ILocalVariable Variable {
7729 public override VariableInfo VariableInfo {
7730 get { return null; }
7735 /// Handles `var' contextual keyword; var becomes a keyword only
7736 /// if no type called var exists in a variable scope
7738 class VarExpr : SimpleName
7740 public VarExpr (Location loc)
7745 public bool InferType (ResolveContext ec, Expression right_side)
7748 throw new InternalErrorException ("An implicitly typed local variable could not be redefined");
7750 type = right_side.Type;
7751 if (type == InternalType.NullLiteral || type.Kind == MemberKind.Void || type == InternalType.AnonymousMethod || type == InternalType.MethodGroup) {
7752 ec.Report.Error (815, loc,
7753 "An implicitly typed local variable declaration cannot be initialized with `{0}'",
7754 type.GetSignatureForError ());
7755 type = InternalType.ErrorType;
7759 eclass = ExprClass.Variable;
7763 protected override void Error_TypeOrNamespaceNotFound (IMemberContext ec)
7765 if (ec.Module.Compiler.Settings.Version < LanguageVersion.V_3)
7766 base.Error_TypeOrNamespaceNotFound (ec);
7768 ec.Module.Compiler.Report.Error (825, loc, "The contextual keyword `var' may only appear within a local variable declaration");