Ejemplo n.º 1
0
        IType[] OutputTypes(ResolveResult e, IType t)
        {
            // C# 4.0 spec: §7.5.2.4 Output types
            LambdaResolveResult lrr = e as LambdaResolveResult;

            if (lrr != null || e is MethodGroupResolveResult)
            {
                IMethod m = GetDelegateOrExpressionTreeSignature(t);
                if (m != null)
                {
                    return(new[] { m.ReturnType });
                }
            }
            return(emptyTypeArray);
        }
Ejemplo n.º 2
0
        void MakeExplicitParameterTypeInference(LambdaResolveResult e, IType t)
        {
            // C# 4.0 spec: §7.5.2.7 Explicit parameter type inferences
            if (e.IsImplicitlyTyped || !e.HasParameterList)
            {
                return;
            }
            Log.WriteLine(" MakeExplicitParameterTypeInference from " + e + " to " + t);
            IMethod m = GetDelegateOrExpressionTreeSignature(t);

            if (m == null)
            {
                return;
            }
            for (int i = 0; i < e.Parameters.Count && i < m.Parameters.Count; i++)
            {
                MakeExactInference(e.Parameters[i].Type, m.Parameters[i].Type);
            }
        }
Ejemplo n.º 3
0
        IType[] InputTypes(ResolveResult e, IType t)
        {
            // C# 4.0 spec: §7.5.2.3 Input types
            LambdaResolveResult lrr = e as LambdaResolveResult;

            if (lrr != null && lrr.IsImplicitlyTyped || e is MethodGroupResolveResult)
            {
                IMethod m = GetDelegateOrExpressionTreeSignature(t);
                if (m != null)
                {
                    IType[] inputTypes = new IType[m.Parameters.Count];
                    for (int i = 0; i < inputTypes.Length; i++)
                    {
                        inputTypes[i] = m.Parameters[i].Type;
                    }
                    return(inputTypes);
                }
            }
            return(emptyTypeArray);
        }
Ejemplo n.º 4
0
        void PhaseOne()
        {
            // C# 4.0 spec: §7.5.2.1 The first phase
            Log.WriteLine("Phase One");
            for (int i = 0; i < arguments.Length; i++)
            {
                ResolveResult Ei = arguments[i];
                IType         Ti = parameterTypes[i];

                LambdaResolveResult lrr = Ei as LambdaResolveResult;
                if (lrr != null)
                {
                    MakeExplicitParameterTypeInference(lrr, Ti);
                }
                if (lrr != null || Ei is MethodGroupResolveResult)
                {
                    // this is not in the spec???
                    if (OutputTypeContainsUnfixed(Ei, Ti) && !InputTypesContainsUnfixed(Ei, Ti))
                    {
                        MakeOutputTypeInference(Ei, Ti);
                    }
                }

                if (IsValidType(Ei.Type))
                {
                    if (Ti is ByReferenceType)
                    {
                        MakeExactInference(Ei.Type, Ti);
                    }
                    else
                    {
                        MakeLowerBoundInference(Ei.Type, Ti);
                    }
                }
            }
        }
Ejemplo n.º 5
0
        void MakeOutputTypeInference(ResolveResult e, IType t)
        {
            Log.WriteLine(" MakeOutputTypeInference from " + e + " to " + t);
            // If E is an anonymous function with inferred return type  U (§7.5.2.12) and T is a delegate type or expression
            // tree type with return type Tb, then a lower-bound inference (§7.5.2.9) is made from U to Tb.
            LambdaResolveResult lrr = e as LambdaResolveResult;

            if (lrr != null)
            {
                IMethod m = GetDelegateOrExpressionTreeSignature(t);
                if (m != null)
                {
                    IType inferredReturnType;
                    if (lrr.IsImplicitlyTyped)
                    {
                        if (m.Parameters.Count != lrr.Parameters.Count)
                        {
                            return;                             // cannot infer due to mismatched parameter lists
                        }
                        TypeParameterSubstitution substitution = GetSubstitutionForFixedTPs();
                        IType[] inferredParameterTypes         = new IType[m.Parameters.Count];
                        for (int i = 0; i < inferredParameterTypes.Length; i++)
                        {
                            IType parameterType = m.Parameters[i].Type;
                            inferredParameterTypes[i] = parameterType.AcceptVisitor(substitution);
                        }
                        inferredReturnType = lrr.GetInferredReturnType(inferredParameterTypes);
                    }
                    else
                    {
                        inferredReturnType = lrr.GetInferredReturnType(null);
                    }
                    MakeLowerBoundInference(inferredReturnType, m.ReturnType);
                    return;
                }
            }
            // Otherwise, if E is a method group and T is a delegate type or expression tree type
            // with parameter types T1…Tk and return type Tb, and overload resolution
            // of E with the types T1…Tk yields a single method with return type U, then a lower­-bound
            // inference is made from U to Tb.
            MethodGroupResolveResult mgrr = e as MethodGroupResolveResult;

            if (mgrr != null)
            {
                IMethod m = GetDelegateOrExpressionTreeSignature(t);
                if (m != null)
                {
                    ResolveResult[]           args         = new ResolveResult[m.Parameters.Count];
                    TypeParameterSubstitution substitution = GetSubstitutionForFixedTPs();
                    for (int i = 0; i < args.Length; i++)
                    {
                        IParameter param         = m.Parameters[i];
                        IType      parameterType = param.Type.AcceptVisitor(substitution);
                        if ((param.IsRef || param.IsOut) && parameterType.Kind == TypeKind.ByReference)
                        {
                            parameterType = ((ByReferenceType)parameterType).ElementType;
                            args[i]       = new ByReferenceResolveResult(parameterType, param.IsOut);
                        }
                        else
                        {
                            args[i] = new ResolveResult(parameterType);
                        }
                    }
                    var or = mgrr.PerformOverloadResolution(compilation,
                                                            args,
                                                            allowExpandingParams: false, allowOptionalParameters: false);
                    if (or.FoundApplicableCandidate && or.BestCandidateAmbiguousWith == null)
                    {
                        IType returnType = or.GetBestCandidateWithSubstitutedTypeArguments().ReturnType;
                        MakeLowerBoundInference(returnType, m.ReturnType);
                    }
                }
                return;
            }
            // Otherwise, if E is an expression with type U, then a lower-bound inference is made from U to T.
            if (IsValidType(e.Type))
            {
                MakeLowerBoundInference(e.Type, t);
            }
        }