C# NewExpression类代码示例

		ISemantic E(NewExpression nex)
		{
			// http://www.d-programming-language.org/expression.html#NewExpression
			ISemantic[] possibleTypes = null;

			if (nex.Type is IdentifierDeclaration)
				possibleTypes = TypeDeclarationResolver.Resolve((IdentifierDeclaration)nex.Type, ctxt, filterForTemplateArgs: false);
			else
				possibleTypes = TypeDeclarationResolver.Resolve(nex.Type, ctxt);
			
			var ctors = new Dictionary<DMethod, TemplateIntermediateType>();

			if (possibleTypes == null)
				return null;

			foreach (var t in possibleTypes)
			{
				var ct = DResolver.StripAliasSymbol(t as AbstractType) as TemplateIntermediateType;
				if (ct!=null && 
					!ct.Definition.ContainsAttribute(DTokens.Abstract))
					foreach (var ctor in GetConstructors(ct))
						ctors.Add(ctor, ct);
			}

			MemberSymbol finalCtor = null;

			var kvArray = ctors.ToArray();

			/*
			 * TODO: Determine argument types and filter out ctor overloads.
			 */

			if (kvArray.Length != 0)
				finalCtor = new MemberSymbol(kvArray[0].Key, kvArray[0].Value, nex);
			else if (possibleTypes.Length != 0)
				return AbstractType.Get(possibleTypes[0]);

			return finalCtor;
		}

 /// <summary>
 /// Creates a new expression that is like this one, but using the
 /// supplied children. If all of the children are the same, it will
 /// return this expression.
 /// </summary>
 /// <param name="newExpression">The <see cref="NewExpression" /> property of the result.</param>
 /// <param name="bindings">The <see cref="Bindings" /> property of the result.</param>
 /// <returns>This expression if no children changed, or an expression with the updated children.</returns>
 public MemberInitExpression Update(NewExpression newExpression, IEnumerable<MemberBinding> bindings) {
     if (newExpression == NewExpression && bindings == Bindings) {
         return this;
     }
     return Expression.MemberInit(newExpression, bindings);
 }

 protected internal virtual void PostWalk(NewExpression node) { }

 public virtual void PostWalk(NewExpression node)
 {
 }

        private static void HandleNewExpression_Ctor(NewExpression nex, IBlockNode curBlock, List<AbstractType> _ctors, AbstractType t)
        {
            var udt = t as TemplateIntermediateType;
            if (udt is ClassType || udt is StructType)
            {
                bool explicitCtorFound = false;
                var constructors = new List<DMethod>();

                //TODO: Mixed-in ctors? --> Convert to AbstractVisitor/use NameScan
                foreach (var member in udt.Definition)
                {
                    var dm = member as DMethod;

                    if (dm != null && dm.SpecialType == DMethod.MethodType.Constructor)
                    {
                        explicitCtorFound = true;
                        if (!dm.IsPublic)
                        {
                            var curNode = curBlock;
                            bool pass = false;
                            do
                            {
                                if (curNode == udt.Definition)
                                {
                                    pass = true;
                                    break;
                                }
                            }
                            while ((curNode = curNode.Parent as IBlockNode) != curNode);

                            if (!pass)
                                continue;
                        }

                        constructors.Add(dm);
                    }
                }

                if (constructors.Count == 0)
                {
                    if (explicitCtorFound)
                    {
                        // TODO: Somehow inform the user that the current class can't be instantiated
                    }
                    else
                    {
                        // Introduce default constructor
                        constructors.Add(new DMethod(DMethod.MethodType.Constructor)
                        {
                            Description = "Default constructor for " + udt.Name,
                            Parent = udt.Definition
                        });
                    }
                }

                // Wrapp all ctor members in MemberSymbols
                foreach (var ctor in constructors)
                    _ctors.Add(new MemberSymbol(ctor, t, nex.Type));
            }
        }

        static void CalculateCurrentArgument(NewExpression nex, 
			ArgumentsResolutionResult res, 
			CodeLocation caretLocation, 
			ResolutionContext ctxt,
			IEnumerable<AbstractType> resultBases=null)
        {
            if (nex.Arguments != null)
                res.CurrentlyTypedArgumentIndex = nex.Arguments.Length;
                /*{
                int i = 0;
                foreach (var arg in nex.Arguments)
                {
                    if (caretLocation >= arg.Location && caretLocation <= arg.EndLocation)
                    {
                        res.CurrentlyTypedArgumentIndex = i;
                        break;
                    }
                    i++;
                }
            }*/
        }

        static void HandleNewExpression(NewExpression nex, 
			ArgumentsResolutionResult res, 
			IEditorData Editor, 
			ResolverContextStack ctxt,
			IBlockNode curBlock)
        {
            res.MethodIdentifier = nex;
            CalculateCurrentArgument(nex, res, Editor.CaretLocation, ctxt);

            var type = TypeDeclarationResolver.ResolveSingle(nex.Type, ctxt) as ClassType;

            //TODO: Inform the user that only classes can be instantiated
            if (type != null)
            {
                var constructors = new List<DMethod>();
                bool explicitCtorFound = false;

                foreach (var member in type.Definition)
                {
                    var dm = member as DMethod;

                    if (dm != null && dm.SpecialType == DMethod.MethodType.Constructor)
                    {
                        explicitCtorFound = true;
                        if (!dm.IsPublic)
                        {
                            var curNode = curBlock;
                            bool pass = false;
                            do
                            {
                                if (curNode == type.Definition)
                                {
                                    pass = true;
                                    break;
                                }
                            }
                            while ((curNode = curNode.Parent as IBlockNode) != curNode);

                            if (!pass)
                                continue;
                        }

                        constructors.Add(dm);
                    }
                }

                if (constructors.Count == 0)
                {
                    if (explicitCtorFound)
                    {
                        // TODO: Somehow inform the user that the current class can't be instantiated
                    }
                    else
                    {
                        // Introduce default constructor
                        constructors.Add(new DMethod(DMethod.MethodType.Constructor)
                        {
                            Description = "Default constructor for " + type.Name,
                            Parent = type.Definition
                        });
                    }
                }

                // Wrapp all ctor members in MemberSymbols
                var _ctors = new List<AbstractType>();
                foreach (var ctor in constructors)
                    _ctors.Add(new MemberSymbol(ctor, type, nex.Type));
                res.ResolvedTypesOrMethods = _ctors.ToArray();

                //TODO: Probably pre-select the current ctor by handling previously typed arguments etc.
            }
        }

 /// <summary>
 /// Creates a new expression that is like this one, but using the
 /// supplied children. If all of the children are the same, it will
 /// return this expression.
 /// </summary>
 /// <param name="newExpression">The <see cref="NewExpression" /> property of the result.</param>
 /// <param name="initializers">The <see cref="Initializers" /> property of the result.</param>
 /// <returns>This expression if no children changed, or an expression with the updated children.</returns>
 public ListInitExpression Update(NewExpression newExpression, IEnumerable<ElementInit> initializers) {
     if (newExpression == NewExpression && initializers == Initializers) {
         return this;
     }
     return Expression.ListInit(newExpression, initializers);
 }

		public void Visit(NewExpression nex)
		{
			res.MethodIdentifier = nex;
			CalculateCurrentArgument(nex, res, Editor.CaretLocation, ctxt);

			var type = TypeDeclarationResolver.ResolveSingle(nex.Type, ctxt);

			var _ctors = new List<AbstractType>();

			if (type is AmbiguousType)
				foreach (var t in (type as AmbiguousType).Overloads)
					HandleNewExpression_Ctor(nex, curScope, _ctors, t);
			else
				HandleNewExpression_Ctor(nex, curScope, _ctors, type);

			res.ResolvedTypesOrMethods = _ctors.ToArray();
		}

		private static void HandleNewExpression_Ctor(NewExpression nex, IBlockNode curBlock, List<AbstractType> _ctors, AbstractType t)
		{
			var udt = t as TemplateIntermediateType;
			if (udt is ClassType || udt is StructType)
			{
				bool explicitCtorFound;
				
				if (!CtorScan.ScanForConstructors(nex, curBlock, udt, _ctors, out explicitCtorFound))
				{
					if (explicitCtorFound)
					{
						// TODO: Somehow inform the user that the current class can't be instantiated
					}
					else
					{
						// Introduce default constructor
						_ctors.Add(new MemberSymbol(new DMethod(DMethod.MethodType.Constructor)
						{
							Description = "Default constructor for " + udt.Name,
							Parent = udt.Definition
						}, udt));
					}
				}
			}
		}

			public static bool ScanForConstructors(NewExpression sr, IBlockNode scope, UserDefinedType udt, List<AbstractType> _ctors, out bool explicitCtorFound)
			{
				explicitCtorFound = false;
				var ct = new CtorScan(sr, new ResolutionContext(new Misc.LegacyParseCacheView(new RootPackage[] {}), null, scope));
				ct.DeepScanClass(udt, new ItemCheckParameters(MemberFilter.Methods), false);

				_ctors.AddRange(ct.matches_types);

				var rawList = (udt.Definition as DClassLike)[DMethod.ConstructorIdentifierHash];
				if(rawList != null)
				{
					foreach(var n in rawList)
					{
						var dm = n as DMethod;
						if(dm == null || dm.IsStatic || dm.SpecialType != DMethod.MethodType.Constructor)
							continue;

						explicitCtorFound = true;
						break;
					}
				}

				return ct.matches_types.Count != 0;
			}

 internal MemberInitExpression(NewExpression newExpression, ReadOnlyCollection<MemberBinding> bindings) {
     _newExpression = newExpression;
     _bindings = bindings;
 }

 ///<summary>Creates a <see cref="T:System.Linq.Expressions.MemberInitExpression" />.</summary>
 ///<returns>A <see cref="T:System.Linq.Expressions.MemberInitExpression" /> that has the <see cref="P:System.Linq.Expressions.Expression.NodeType" /> property equal to <see cref="F:System.Linq.Expressions.ExpressionType.MemberInit" /> and the <see cref="P:System.Linq.Expressions.MemberInitExpression.NewExpression" /> and <see cref="P:System.Linq.Expressions.MemberInitExpression.Bindings" /> properties set to the specified values.</returns>
 ///<param name="newExpression">A <see cref="T:System.Linq.Expressions.NewExpression" /> to set the <see cref="P:System.Linq.Expressions.MemberInitExpression.NewExpression" /> property equal to.</param>
 ///<param name="bindings">An <see cref="T:System.Collections.Generic.IEnumerable`1" /> that contains <see cref="T:System.Linq.Expressions.MemberBinding" /> objects to use to populate the <see cref="P:System.Linq.Expressions.MemberInitExpression.Bindings" /> collection.</param>
 ///<exception cref="T:System.ArgumentNullException">
 ///<paramref name="newExpression" /> or <paramref name="bindings" /> is null.</exception>
 ///<exception cref="T:System.ArgumentException">The <see cref="P:System.Linq.Expressions.MemberBinding.Member" /> property of an element of <paramref name="bindings" /> does not represent a member of the type that <paramref name="newExpression" />.Type represents.</exception>
 public static MemberInitExpression MemberInit(NewExpression newExpression, IEnumerable<MemberBinding> bindings) {
     ContractUtils.RequiresNotNull(newExpression, "newExpression");
     ContractUtils.RequiresNotNull(bindings, "bindings");
     var roBindings = bindings.ToReadOnly();
     ValidateMemberInitArgs(newExpression.Type, roBindings);
     return new MemberInitExpression(newExpression, roBindings);
 }

 /// <summary>
 /// Creates a <see cref="ListInitExpression"/> that uses a method named "Add" to add elements to a collection.
 /// </summary>
 /// <param name="newExpression">A <see cref="NewExpression"/> to set the <see cref="P:ListInitExpression.NewExpression"/> property equal to.</param>
 /// <param name="initializers">An array of <see cref="Expression"/> objects to use to populate the <see cref="ListInitExpression.Initializers"/> collection.</param>
 /// <returns>A <see cref="ListInitExpression"/> that has the <see cref="P:ListInitExpression.NodeType"/> property equal to ListInit and the <see cref="P:ListInitExpression.NewExpression"/> property set to the specified value.</returns>
 public static ListInitExpression ListInit(NewExpression newExpression, params Expression[] initializers) {
     ContractUtils.RequiresNotNull(newExpression, "newExpression");
     ContractUtils.RequiresNotNull(initializers, "initializers");
     return ListInit(newExpression, initializers as IEnumerable<Expression>);
 }

        public void Visit(NewExpression expression)
        {
            outStream.Write("new ");
            expression.Function.Accept(this);
            outStream.Write("(");

            if (expression.Arguments.Count > 0)
            {
                expression.Arguments.First().Accept(this);

                foreach (var a in expression.Arguments.Skip(1))
                {
                    outStream.Write(", ");
                    a.Accept(this);
                }
            }

            outStream.Write(")");
        }