C# IReturnType.CastToArrayReturnType方法代码示例

			/// <summary>
			/// Gets whether this type parameter occurs in the specified return type.
			/// </summary>
			public bool OccursIn(IReturnType rt)
			{
				ArrayReturnType art = rt.CastToArrayReturnType();
				if (art != null) {
					return OccursIn(art.ArrayElementType);
				}
				ConstructedReturnType crt = rt.CastToConstructedReturnType();
				if (crt != null) {
					return crt.TypeArguments.Any(ta => OccursIn(ta));
				}
				GenericReturnType grt = rt.CastToGenericReturnType();
				if (grt != null) {
					return this.TypeParameter.Equals(grt.TypeParameter);
				}
				return false;
			}

		bool CheckReturnType(IReturnType t)
		{
			if (t.IsGenericReturnType) {
				return t.CastToGenericReturnType().TypeParameter.Method == null;
			} else if (t.IsArrayReturnType) {
				return CheckReturnType(t.CastToArrayReturnType().ArrayElementType);
			} else if (t.IsConstructedReturnType) {
				foreach (IReturnType para in t.CastToConstructedReturnType().TypeArguments) {
					if (para != null) {
						if (CheckReturnType(para)) return true;
					}
				}
				return false;
			} else {
				return false;
			}
		}

		static void UnpackArrayType(StringBuilder builder, IReturnType returnType)
		{
			if (returnType.IsArrayReturnType) {
				builder.Append('[');
				int dimensions = returnType.CastToArrayReturnType().ArrayDimensions;
				for (int i = 1; i < dimensions; ++i) {
					builder.Append(',');
				}
				builder.Append(']');
				UnpackArrayType(builder, returnType.CastToArrayReturnType().ArrayElementType);
			}
		}

		static IReturnType GetElementType(IReturnType potentialArrayType)
		{
			if (potentialArrayType == null)
				return null;
			ArrayReturnType result;
			while ((result = potentialArrayType.CastToArrayReturnType()) != null) {
				potentialArrayType = result.ArrayElementType;
			}
			return potentialArrayType;
		}

		void UnpackNestedType(StringBuilder builder, IReturnType returnType)
		{
			if (returnType.IsArrayReturnType) {
				builder.Append('(');
				int dimensions = returnType.CastToArrayReturnType().ArrayDimensions;
				for (int i = 1; i < dimensions; ++i) {
					builder.Append(',');
				}
				builder.Append(')');
				UnpackNestedType(builder, returnType.CastToArrayReturnType().ArrayElementType);
			} else if (returnType.IsConstructedReturnType) {
				UnpackNestedType(builder, returnType.CastToConstructedReturnType().UnboundType);
				builder.Append("(Of ");
				IList<IReturnType> ta = returnType.CastToConstructedReturnType().TypeArguments;
				for (int i = 0; i < ta.Count; ++i) {
					if (i > 0) builder.Append(", ");
					builder.Append(Convert(ta[i]));
				}
				builder.Append(')');
			}
		}

			void WriteType(IReturnType rt)
			{
				if (rt == null) {
					writer.Write(NullRTReferenceCode);
					return;
				}
				if (rt.IsDefaultReturnType) {
					string name = rt.FullyQualifiedName;
					if (name == "System.Void") {
						writer.Write(VoidRTCode);
					} else {
						writer.Write(classIndices[new ClassNameTypeCountPair(rt)]);
					}
				} else if (rt.IsGenericReturnType) {
					GenericReturnType grt = rt.CastToGenericReturnType();
					if (grt.TypeParameter.Method != null) {
						writer.Write(MethodGenericRTCode);
					} else {
						writer.Write(TypeGenericRTCode);
					}
					writer.Write(grt.TypeParameter.Index);
				} else if (rt.IsArrayReturnType) {
					writer.Write(ArrayRTCode);
					writer.Write(rt.CastToArrayReturnType().ArrayDimensions);
					WriteType(rt.CastToArrayReturnType().ArrayElementType);
				} else if (rt.IsConstructedReturnType) {
					ConstructedReturnType crt = rt.CastToConstructedReturnType();
					writer.Write(ConstructedRTCode);
					WriteType(crt.UnboundType);
					writer.Write((byte)crt.TypeArguments.Count);
					foreach (IReturnType typeArgument in crt.TypeArguments) {
						WriteType(typeArgument);
					}
				} else if (rt.IsDecoratingReturnType<PointerReturnType>()) {
					writer.Write(PointerRTCode);
					WriteType(rt.CastToDecoratingReturnType<PointerReturnType>().BaseType);
				} else {
					writer.Write(NullRTReferenceCode);
					LoggingService.Warn("Unknown return type: " + rt.ToString());
				}
			}

			void AddExternalType(IReturnType rt, List<ClassNameTypeCountPair> externalTypes, int classCount)
			{
				if (rt.IsDefaultReturnType) {
					ClassNameTypeCountPair pair = new ClassNameTypeCountPair(rt);
					if (!classIndices.ContainsKey(pair)) {
						classIndices.Add(pair, externalTypes.Count + classCount);
						externalTypes.Add(pair);
					}
				} else if (rt.IsGenericReturnType) {
					// ignore
				} else if (rt.IsArrayReturnType) {
					AddExternalType(rt.CastToArrayReturnType().ArrayElementType, externalTypes, classCount);
				} else if (rt.IsConstructedReturnType) {
					AddExternalType(rt.CastToConstructedReturnType().UnboundType, externalTypes, classCount);
					foreach (IReturnType typeArgument in rt.CastToConstructedReturnType().TypeArguments) {
						AddExternalType(typeArgument, externalTypes, classCount);
					}
				} else if (rt.IsDecoratingReturnType<PointerReturnType>()) {
					AddExternalType(rt.CastToDecoratingReturnType<PointerReturnType>().BaseType, externalTypes, classCount);
				} else {
					LoggingService.Warn("Unknown return type: " + rt.ToString());
				}
			}

		static int GetMoreSpecific(IReturnType r, IReturnType s)
		{
			if (r == null && s == null) return 0;
			if (r == null) return 2;
			if (s == null) return 1;
			if (r.IsGenericReturnType && !(s.IsGenericReturnType))
				return 2;
			if (s.IsGenericReturnType && !(r.IsGenericReturnType))
				return 1;
			if (r.IsArrayReturnType && s.IsArrayReturnType)
				return GetMoreSpecific(r.CastToArrayReturnType().ArrayElementType, s.CastToArrayReturnType().ArrayElementType);
			if (r.IsConstructedReturnType && s.IsConstructedReturnType)
				return GetMoreSpecific(r.CastToConstructedReturnType().TypeArguments, s.CastToConstructedReturnType().TypeArguments);
			return 0;
		}

		static bool AreTypesDifferent(IReturnType oldType, CodeTypeReference newType)
		{
			IClass oldClass = oldType.GetUnderlyingClass();
			if (oldClass == null) {
				// ignore type changes to untyped VB fields
				return false;
			}
			if (newType.BaseType == "System.Void") {
				// field types get replaced with System.Void if the type cannot be resolved
				// (e.g. generic fields in the Boo designer which aren't converted to CodeDom)
				// we'll ignore such type changes (fields should never have the type void)
				return false;
			}
			
			ArrayReturnType oldArray = oldType.IsArrayReturnType ? oldType.CastToArrayReturnType() : null;
			if (oldArray == null ^ newType.ArrayRank < 1)
			{
				return true;
			}
			
			if (oldArray == null) {
				
				if (oldClass.DotNetName != newType.BaseType) {
					return true;
				}
				
			} else {
				
				if (oldArray.ArrayDimensions != newType.ArrayRank) {
					return true;
				}
				if (AreTypesDifferent(oldArray.ArrayElementType, newType.ArrayElementType)) {
					return true;
				}
				
			}
			
			return false;
		}

		/// <summary>
		/// Checks if an implicit conversion exists from <paramref name="from"/> to <paramref name="to"/>.
		/// </summary>
		public static bool ConversionExists(IReturnType from, IReturnType to)
		{
			// ECMA-334, § 13.1 Implicit conversions
			
			// Identity conversion:
			if (from == to) return true;
			if (from == null || to == null) return false;
			if (from.Equals(to)) {
				return true;
			}
			
			bool fromIsDefault = from.IsDefaultReturnType;
			bool toIsDefault = to.IsDefaultReturnType;
			
			if (fromIsDefault && toIsDefault) {
				// Implicit numeric conversions:
				int f = GetPrimitiveType(from);
				int t = GetPrimitiveType(to);
				if (f == SByte && (t == Short || t == Int || t == Long || t == Float || t == Double || t == Decimal))
					return true;
				if (f == Byte && (t == Short || t == UShort || t == Int || t == UInt || t == Long || t == ULong || t == Float || t == Double || t == Decimal))
					return true;
				if (f == Short && (t == Int || t == Long || t == Float || t == Double || t == Decimal))
					return true;
				if (f == UShort && (t == Int || t == UInt || t == Long || t == ULong || t == Float || t == Double || t == Decimal))
					return true;
				if (f == Int && (t == Long || t == Float || t == Double || t == Decimal))
					return true;
				if (f == UInt && (t == Long || t == ULong || t == Float || t == Double || t == Decimal))
					return true;
				if ((f == Long || f == ULong) && (t == Float || t == Double || t == Decimal))
					return true;
				if (f == Char && (t == UShort || t == Int || t == UInt || t == Long || t == ULong || t == Float || t == Double || t == Decimal))
					return true;
				if (f == Float && t == Double)
					return true;
			}
			// Implicit reference conversions:
			
			if (toIsDefault && to.FullyQualifiedName == "System.Object") {
				return true; // from any type to object
			}
			if (toIsDefault && (fromIsDefault || from.IsArrayReturnType)) {
				IClass c1 = from.GetUnderlyingClass();
				IClass c2 = to.GetUnderlyingClass();
				if (c1 != null && c1.IsTypeInInheritanceTree(c2)) {
					return true;
				}
			}
			if (from.IsArrayReturnType && to.IsArrayReturnType) {
				ArrayReturnType fromArt = from.CastToArrayReturnType();
				ArrayReturnType toArt   = to.CastToArrayReturnType();
				// from array to other array type
				if (fromArt.ArrayDimensions == toArt.ArrayDimensions) {
					return ConversionExists(fromArt.ArrayElementType, toArt.ArrayElementType);
				}
			}
			
			if (from.IsConstructedReturnType && to.IsConstructedReturnType) {
				if (from.FullyQualifiedName == to.FullyQualifiedName) {
					IList<IReturnType> fromTypeArguments = from.CastToConstructedReturnType().TypeArguments;
					IList<IReturnType> toTypeArguments = to.CastToConstructedReturnType().TypeArguments;
					if (fromTypeArguments.Count == toTypeArguments.Count) {
						for (int i = 0; i < fromTypeArguments.Count; i++) {
							if (fromTypeArguments[i] == toTypeArguments[i])
								continue;
							if (object.Equals(fromTypeArguments[i], toTypeArguments[i]))
								continue;
							if (!(toTypeArguments[i].IsGenericReturnType))
								return false;
						}
						return true;
					}
				}
			}
			
			return false;
		}

		/// <summary>
		/// Infers type arguments specified by passing expectedArgument as parameter where passedArgument
		/// was expected. The resulting type arguments are written to outputArray.
		/// Returns false when expectedArgument and passedArgument are incompatible, otherwise true
		/// is returned (true is used both for successful inferring and other kind of errors).
		/// </summary>
		public static bool InferTypeArgument(IReturnType expectedArgument, IReturnType passedArgument, IReturnType[] outputArray)
		{
			if (expectedArgument == null) return true;
			if (passedArgument == null) return true; // TODO: NullTypeReference
			if (expectedArgument.IsArrayReturnType) {
				IReturnType expectedArrayElementType = expectedArgument.CastToArrayReturnType().ArrayElementType;
				if (passedArgument.IsArrayReturnType && expectedArgument.CastToArrayReturnType().ArrayDimensions == passedArgument.CastToArrayReturnType().ArrayDimensions) {
					return InferTypeArgument(expectedArrayElementType, passedArgument.CastToArrayReturnType().ArrayElementType, outputArray);
				} else if (passedArgument.IsConstructedReturnType) {
					switch (passedArgument.FullyQualifiedName) {
						case "System.Collections.Generic.IList":
						case "System.Collections.Generic.ICollection":
						case "System.Collections.Generic.IEnumerable":
							return InferTypeArgument(expectedArrayElementType, passedArgument.CastToConstructedReturnType().TypeArguments[0], outputArray);
					}
				}
				// If P is an array type, and A is not an array type of the same rank,
				// or an instantiation of IList<>, ICollection<>, or IEnumerable<>, then
				// type inference fails for the generic method.
				return false;
			}
			if (expectedArgument.IsGenericReturnType) {
				GenericReturnType methodTP = expectedArgument.CastToGenericReturnType();
				if (methodTP.TypeParameter.Method != null) {
					if (methodTP.TypeParameter.Index < outputArray.Length) {
						outputArray[methodTP.TypeParameter.Index] = passedArgument;
					}
					return true;
				}
			}
			if (expectedArgument.IsConstructedReturnType) {
				// The spec for this case is quite complex.
				// For our purposes, we can simplify enourmously:
				if (!passedArgument.IsConstructedReturnType) return false;
				
				IList<IReturnType> expectedTA = expectedArgument.CastToConstructedReturnType().TypeArguments;
				IList<IReturnType> passedTA   = passedArgument.CastToConstructedReturnType().TypeArguments;
				
				int count = Math.Min(expectedTA.Count, passedTA.Count);
				for (int i = 0; i < count; i++) {
					InferTypeArgument(expectedTA[i], passedTA[i], outputArray);
				}
			}
			return true;
		}

		void UnpackNestedType(StringBuilder builder, IReturnType returnType)
		{
			if (returnType.IsArrayReturnType) {
				ArrayReturnType art = returnType.CastToArrayReturnType();
				builder.Append('(');
				UnpackNestedType(builder, art.ArrayElementType);
				if (art.ArrayDimensions > 1) {
					builder.Append(',');
					builder.Append(art.ArrayDimensions);
				}
				builder.Append(')');
			} else if (returnType.IsConstructedReturnType) {
				ConstructedReturnType crt = returnType.CastToConstructedReturnType();
				UnpackNestedType(builder, crt.UnboundType);
				builder.Append("[of ");
				for (int i = 0; i < crt.TypeArguments.Count; ++i) {
					if (i > 0) builder.Append(", ");
					builder.Append(Convert(crt.TypeArguments[i]));
				}
				builder.Append(']');
			} else {
				string fullName = returnType.FullyQualifiedName;
				if (fullName != null && typeConversionTable.ContainsKey(fullName)) {
					builder.Append(typeConversionTable[fullName].ToString());
				} else {
					if (UseFullyQualifiedTypeNames) {
						builder.Append(fullName);
					} else {
						builder.Append(returnType.Name);
					}
				}
			}
		}

		/// <summary>
		/// Make lower bound inference from U for V.
		/// </summary>
		void MakeLowerBoundInference(IReturnType U, IReturnType V)
		{
			Log(" MakeLowerBoundInference from " + U + " for " + V);
			if (U == null || V == null)
				return;
			
			// If V is one of the unfixed Xi then U is added to the set of bounds for Xi.
			TP tp = GetTPForType(V);
			if (tp != null && tp.Fixed == false) {
				Log("  Add bound '" + U.DotNetName + "' to " + tp);
				tp.Bounds.Add(U);
				return;
			}
			// Otherwise if U is an array type Ue[…] and V is either an array type Ve[…]of the
			// same rank, or if U is a one­dimensional array type Ue[]and V is one of
			// IEnumerable<Ve>, ICollection<Ve> or IList<Ve> then
			ArrayReturnType arrU = U.CastToArrayReturnType();
			ArrayReturnType arrV = V.CastToArrayReturnType();
			ConstructedReturnType CV = V.CastToConstructedReturnType();
			if (arrU != null &&
			    (arrV != null && arrU.ArrayDimensions == arrV.ArrayDimensions
			     || (arrU.ArrayDimensions == 1 && IsIEnumerableCollectionOrList(CV))))
			{
				IReturnType Ue = arrU.ArrayElementType;
				IReturnType Ve = arrV != null ? arrV.ArrayElementType : CV.TypeArguments[0];
				// If Ue is known to be a reference type then a lower­bound inference from Ue to Ve is made
				if (IsReferenceType(Ue) ?? false) {
					MakeLowerBoundInference(Ue, Ve);
				} else {
					// Otherwise an exact inference from Ue to Ve is made
					MakeExactInference(Ue, Ve);
				}
				return;
			}
			// Otherwise if V is a constructed type C<V1…Vk> and there is a unique set of
			// types U1…Uk such that a standard implicit conversion exists from U to C<U1…Uk>
			// then an exact inference is made from each Ui for the corresponding Vi.
			if (CV != null) {
				foreach (IReturnType U2 in MemberLookupHelper.GetTypeInheritanceTree(U)) {
					ConstructedReturnType CU2 = U2.CastToConstructedReturnType();
					if (CU2 != null &&
					    object.Equals(CU2.UnboundType, CV.UnboundType) &&
					    CU2.TypeArgumentCount == CV.TypeArgumentCount
					    && CU2.TypeArguments.Count == CU2.TypeArgumentCount // unfortunately these might not be the same...
					    && CV.TypeArguments.Count == CV.TypeArgumentCount)
					{
						for (int i = 0; i < CU2.TypeArgumentCount; i++) {
							MakeExactInference(CU2.TypeArguments[i], CV.TypeArguments[i]);
						}
						return;
					}
				}
			}
		}

		/// <summary>
		/// Make exact inference from U for V.
		/// </summary>
		void MakeExactInference(IReturnType U, IReturnType V)
		{
			Log(" MakeExactInference from " + U + " for " + V);
			if (U == null || V == null)
				return;
			
			// If V is one of the unfixed Xi then U is added to the set of bounds for Xi.
			TP tp = GetTPForType(V);
			if (tp != null && tp.Fixed == false) {
				Log(" Add bound '" + U.DotNetName + "' to " + tp);
				tp.Bounds.Add(U);
				return;
			}
			// Otherwise if U is an array type Ue[…] and V is an array type Ve[…] of the same rank
			// then an exact inference from Ue to Ve is made
			ArrayReturnType arrU = U.CastToArrayReturnType();
			ArrayReturnType arrV = V.CastToArrayReturnType();
			if (arrU != null && arrV != null && arrU.ArrayDimensions == arrV.ArrayDimensions) {
				MakeExactInference(arrU.ArrayElementType, arrV.ArrayElementType);
				return;
			}
			// Otherwise if V is a constructed type C<V1…Vk> and U is a constructed
			// type C<U1…Uk> then an exact inference is made from each Ui to the corresponding Vi.
			ConstructedReturnType CU = U.CastToConstructedReturnType();
			ConstructedReturnType CV = V.CastToConstructedReturnType();
			if (CU != null && CV != null
			    && object.Equals(CU.UnboundType, CV.UnboundType)
			    && CU.TypeArgumentCount == CV.TypeArgumentCount
			    && CU.TypeArguments.Count == CU.TypeArgumentCount
			    && CV.TypeArguments.Count == CV.TypeArgumentCount)
			{
				for (int i = 0; i < CU.TypeArgumentCount; i++) {
					MakeExactInference(CU.TypeArguments[i], CV.TypeArguments[i]);
				}
				return;
			}
		}

		public static IReturnType TranslateType(IReturnType input, IList<IReturnType> typeParameters, bool convertForMethod)
		{
			if (typeParameters == null || typeParameters.Count == 0) {
				return input; // nothing to do when there are no type parameters specified
			}
			if (input.IsGenericReturnType) {
				GenericReturnType rt = input.CastToGenericReturnType();
				if (convertForMethod ? (rt.TypeParameter.Method != null) : (rt.TypeParameter.Method == null)) {
					if (rt.TypeParameter.Index < typeParameters.Count) {
						IReturnType newType = typeParameters[rt.TypeParameter.Index];
						if (newType != null) {
							return newType;
						}
					}
				}
			} else if (input.IsArrayReturnType) {
				ArrayReturnType arInput = input.CastToArrayReturnType();
				IReturnType e = arInput.ArrayElementType;
				IReturnType t = TranslateType(e, typeParameters, convertForMethod);
				if (e != t && t != null)
					return new ArrayReturnType(arInput.ProjectContent, t, arInput.ArrayDimensions);
			} else if (input.IsConstructedReturnType) {
				ConstructedReturnType cinput = input.CastToConstructedReturnType();
				List<IReturnType> para = new List<IReturnType>(cinput.TypeArguments.Count);
				foreach (IReturnType argument in cinput.TypeArguments) {
					para.Add(TranslateType(argument, typeParameters, convertForMethod));
				}
				return new ConstructedReturnType(cinput.UnboundType, para);
			}
			return input;
		}