public Accessor(ToplevelBlock b, Modifiers mod, Attributes attrs, ParametersCompiled p, Location loc)
 {
     Block = b;
     Attributes = attrs;
     Location = loc;
     Parameters = p;
     ModFlags = ModifiersExtensions.Check (AllowedModifiers, mod, 0, loc, RootContext.ToplevelTypes.Compiler.Report);
 }

		protected bool CheckParentConflictName (ToplevelBlock block, string name, Location l)
		{
			LocalInfo vi = GetLocalInfo (name);
			if (vi != null) {
				block.Report.SymbolRelatedToPreviousError (vi.Location, name);
				if (Explicit == vi.Block.Explicit) {
					Error_AlreadyDeclared (l, name, null);
				} else {
					Error_AlreadyDeclared (l, name, this is ToplevelBlock ?
						"parent or current" : "parent");
				}
				return false;
			}

			if (block != null) {
				var tblock = block.CheckParameterNameConflict (name);
				if (tblock != null) {
					if (block == tblock && block is Linq.QueryBlock)
						Error_AlreadyDeclared (loc, name);
					else
						Error_AlreadyDeclared (loc, name, "parent or current");

					return false;
				}
			}

			return true;
		}

		public static AnonymousTypeClass Create (TypeContainer parent, IList<AnonymousTypeParameter> parameters, Location loc)
		{
			string name = ClassNamePrefix + parent.Module.CounterAnonymousTypes++;

			ParametersCompiled all_parameters;
			TypeParameters tparams = null;
			SimpleName[] t_args;

			if (parameters.Count == 0) {
				all_parameters = ParametersCompiled.EmptyReadOnlyParameters;
				t_args = null;
			} else {
				t_args = new SimpleName[parameters.Count];
				tparams = new TypeParameters ();
				Parameter[] ctor_params = new Parameter[parameters.Count];
				for (int i = 0; i < parameters.Count; ++i) {
					AnonymousTypeParameter p = parameters[i];
					for (int ii = 0; ii < i; ++ii) {
						if (parameters[ii].Name == p.Name) {
							parent.Compiler.Report.Error (833, parameters[ii].Location,
								"`{0}': An anonymous type cannot have multiple properties with the same name",
									p.Name);

							p = new AnonymousTypeParameter (null, "$" + i.ToString (), p.Location);
							parameters[i] = p;
							break;
						}
					}

					t_args[i] = new SimpleName ("<" + p.Name + ">__T", p.Location);
					tparams.Add (new TypeParameter (i, new MemberName (t_args[i].Name, p.Location), null, null, Variance.None));
					ctor_params[i] = new Parameter (t_args[i], p.Name, Parameter.Modifier.NONE, null, p.Location);
				}

				all_parameters = new ParametersCompiled (ctor_params);
			}

			//
			// Create generic anonymous type host with generic arguments
			// named upon properties names
			//
			AnonymousTypeClass a_type = new AnonymousTypeClass (parent.Module, new MemberName (name, tparams, loc), parameters, loc);

			Constructor c = new Constructor (a_type, name, Modifiers.PUBLIC | Modifiers.DEBUGGER_HIDDEN,
				null, all_parameters, loc);
			c.Block = new ToplevelBlock (parent.Module.Compiler, c.ParameterInfo, loc);

			// 
			// Create fields and constructor body with field initialization
			//
			bool error = false;
			for (int i = 0; i < parameters.Count; ++i) {
				AnonymousTypeParameter p = parameters [i];

				Field f = new Field (a_type, t_args [i], Modifiers.PRIVATE | Modifiers.READONLY | Modifiers.DEBUGGER_HIDDEN,
					new MemberName ("<" + p.Name + ">", p.Location), null);

				if (!a_type.AddField (f)) {
					error = true;
					continue;
				}

				c.Block.AddStatement (new StatementExpression (
					new SimpleAssign (new MemberAccess (new This (p.Location), f.Name),
						c.Block.GetParameterReference (i, p.Location))));

				ToplevelBlock get_block = new ToplevelBlock (parent.Module.Compiler, p.Location);
				get_block.AddStatement (new Return (
					new MemberAccess (new This (p.Location), f.Name), p.Location));

				Property prop = new Property (a_type, t_args [i], Modifiers.PUBLIC,
					new MemberName (p.Name, p.Location), null);
				prop.Get = new Property.GetMethod (prop, 0, null, p.Location);
				prop.Get.Block = get_block;
				a_type.AddMember (prop);
			}

			if (error)
				return null;

			a_type.AddConstructor (c);
			return a_type;
		}

		//
		// Creates a proxy base method call inside this container for hoisted base member calls
		//
		public MethodSpec CreateHoistedBaseCallProxy (ResolveContext rc, MethodSpec method)
		{
			Method proxy_method;

			//
			// One proxy per base method is enough
			//
			if (hoisted_base_call_proxies == null) {
				hoisted_base_call_proxies = new Dictionary<MethodSpec, Method> ();
				proxy_method = null;
			} else {
				hoisted_base_call_proxies.TryGetValue (method, out proxy_method);
			}

			if (proxy_method == null) {
				string name = CompilerGeneratedContainer.MakeName (method.Name, null, "BaseCallProxy", hoisted_base_call_proxies.Count);

				MemberName member_name;
				TypeArguments targs = null;
				TypeSpec return_type = method.ReturnType;
				var local_param_types = method.Parameters.Types;

				if (method.IsGeneric) {
					//
					// Copy all base generic method type parameters info
					//
					var hoisted_tparams = method.GenericDefinition.TypeParameters;
					var tparams = new TypeParameters ();

					targs = new TypeArguments ();
					targs.Arguments = new TypeSpec[hoisted_tparams.Length];
					for (int i = 0; i < hoisted_tparams.Length; ++i) {
						var tp = hoisted_tparams[i];
						var local_tp = new TypeParameter (tp, null, new MemberName (tp.Name, Location), null);
						tparams.Add (local_tp);

						targs.Add (new SimpleName (tp.Name, Location));
						targs.Arguments[i] = local_tp.Type;
					}

					member_name = new MemberName (name, tparams, Location);

					//
					// Mutate any method type parameters from original
					// to newly created hoisted version
					//
					var mutator = new TypeParameterMutator (hoisted_tparams, tparams);
					return_type = mutator.Mutate (return_type);
					local_param_types = mutator.Mutate (local_param_types);
				} else {
					member_name = new MemberName (name);
				}

				var base_parameters = new Parameter[method.Parameters.Count];
				for (int i = 0; i < base_parameters.Length; ++i) {
					var base_param = method.Parameters.FixedParameters[i];
					base_parameters[i] = new Parameter (new TypeExpression (local_param_types [i], Location),
						base_param.Name, base_param.ModFlags, null, Location);
					base_parameters[i].Resolve (this, i);
				}

				var cloned_params = ParametersCompiled.CreateFullyResolved (base_parameters, method.Parameters.Types);
				if (method.Parameters.HasArglist) {
					cloned_params.FixedParameters[0] = new Parameter (null, "__arglist", Parameter.Modifier.NONE, null, Location);
					cloned_params.Types[0] = Module.PredefinedTypes.RuntimeArgumentHandle.Resolve ();
				}

				// Compiler generated proxy
				proxy_method = new Method (this, new TypeExpression (return_type, Location),
					Modifiers.PRIVATE | Modifiers.COMPILER_GENERATED | Modifiers.DEBUGGER_HIDDEN,
					member_name, cloned_params, null);

				var block = new ToplevelBlock (Compiler, proxy_method.ParameterInfo, Location) {
					IsCompilerGenerated = true
				};

				var mg = MethodGroupExpr.CreatePredefined (method, method.DeclaringType, Location);
				mg.InstanceExpression = new BaseThis (method.DeclaringType, Location);
				if (targs != null)
					mg.SetTypeArguments (rc, targs);

				// Get all the method parameters and pass them as arguments
				var real_base_call = new Invocation (mg, block.GetAllParametersArguments ());
				Statement statement;
				if (method.ReturnType.Kind == MemberKind.Void)
					statement = new StatementExpression (real_base_call);
				else
					statement = new Return (real_base_call, Location);

				block.AddStatement (statement);
				proxy_method.Block = block;

				members.Add (proxy_method);
				proxy_method.Define ();
				proxy_method.PrepareEmit ();

				hoisted_base_call_proxies.Add (method, proxy_method);
//.........这里部分代码省略.........

			public override void Emit (TypeDefinition parent)
			{
				if ((method.ModFlags & (Modifiers.ABSTRACT | Modifiers.EXTERN)) == 0 && !Compiler.Settings.WriteMetadataOnly) {
					block = new ToplevelBlock (Compiler, ParameterInfo, Location) {
						IsCompilerGenerated = true
					};
					FabricateBodyStatement ();
				}

				base.Emit (parent);
			}

            public DisposeMethod(IteratorStorey host)
                : base(host, TypeManager.system_void_expr, Modifiers.PUBLIC, new MemberName ("Dispose", host.Location))
            {
                host.AddMethod (this);

                Block = new ToplevelBlock (Compiler, host.Iterator.Container, ParametersCompiled.EmptyReadOnlyParameters, Location);
                Block.AddStatement (new DisposeMethodStatement (host.Iterator));
            }

		//
		// Creates a proxy base method call inside this container for hoisted base member calls
		//
		public MethodSpec CreateHoistedBaseCallProxy (ResolveContext rc, MethodSpec method)
		{
			Method proxy_method;

			//
			// One proxy per base method is enough
			//
			if (hoisted_base_call_proxies == null) {
				hoisted_base_call_proxies = new Dictionary<MethodSpec, Method> ();
				proxy_method = null;
			} else {
				hoisted_base_call_proxies.TryGetValue (method, out proxy_method);
			}

			if (proxy_method == null) {
				string name = CompilerGeneratedClass.MakeName (method.Name, null, "BaseCallProxy", hoisted_base_call_proxies.Count);
				var base_parameters = new Parameter[method.Parameters.Count];
				for (int i = 0; i < base_parameters.Length; ++i) {
					var base_param = method.Parameters.FixedParameters[i];
					base_parameters[i] = new Parameter (new TypeExpression (method.Parameters.Types[i], Location),
						base_param.Name, base_param.ModFlags, null, Location);
					base_parameters[i].Resolve (this, i);
				}

				var cloned_params = ParametersCompiled.CreateFullyResolved (base_parameters, method.Parameters.Types);
				if (method.Parameters.HasArglist) {
					cloned_params.FixedParameters[0] = new Parameter (null, "__arglist", Parameter.Modifier.NONE, null, Location);
					cloned_params.Types[0] = Module.PredefinedTypes.RuntimeArgumentHandle.Resolve (Location);
				}

				GenericMethod generic_method;
				MemberName member_name;
				if (method.IsGeneric) {
					//
					// Copy all base generic method type parameters info
					//
					var hoisted_tparams = method.GenericDefinition.TypeParameters;
					var targs = new TypeArguments ();
					var type_params = new TypeParameter[hoisted_tparams.Length];
					for (int i = 0; i < type_params.Length; ++i) {
						var tp = hoisted_tparams[i];
						targs.Add (new TypeParameterName (tp.Name, null, Location));
						type_params[i] = new TypeParameter (tp, this, null, new MemberName (tp.Name), null);
					}

					member_name = new MemberName (name, targs, Location);
					generic_method = new GenericMethod (NamespaceEntry, this, member_name, type_params,
						new TypeExpression (method.ReturnType, Location), cloned_params);
				} else {
					member_name = new MemberName (name);
					generic_method = null;
				}

				// Compiler generated proxy
				proxy_method = new Method (this, generic_method, new TypeExpression (method.ReturnType, Location),
					Modifiers.PRIVATE | Modifiers.COMPILER_GENERATED | Modifiers.DEBUGGER_HIDDEN,
					member_name, cloned_params, null);

				var block = new ToplevelBlock (Compiler, proxy_method.ParameterInfo, Location);

				var mg = MethodGroupExpr.CreatePredefined (method, method.DeclaringType, Location);
				mg.InstanceExpression = new BaseThis (method.DeclaringType, Location);

				// Get all the method parameters and pass them as arguments
				var real_base_call = new Invocation (mg, block.GetAllParametersArguments ());
				Statement statement;
				if (method.ReturnType == TypeManager.void_type)
					statement = new StatementExpression (real_base_call);
				else
					statement = new Return (real_base_call, Location);

				block.AddStatement (statement);
				proxy_method.Block = block;

				methods.Add (proxy_method);
				proxy_method.Define ();

				hoisted_base_call_proxies.Add (method, proxy_method);
			}

			return proxy_method.Spec;
		}

			public override void Emit (DeclSpace parent)
			{
				if ((method.ModFlags & (Modifiers.ABSTRACT | Modifiers.EXTERN)) == 0) {
					block = new ToplevelBlock (Compiler, ParameterInfo, Location);
					FabricateBodyStatement ();
				}

				base.Emit (parent);
			}

			Method GenerateNumberMatcher ()
			{
				var loc = Location;
				var parameters = ParametersCompiled.CreateFullyResolved (
					new [] {
						new Parameter (new TypeExpression (Compiler.BuiltinTypes.Object, loc), "obj", 0, null, loc),
						new Parameter (new TypeExpression (Compiler.BuiltinTypes.Object, loc), "value", 0, null, loc),
						new Parameter (new TypeExpression (Compiler.BuiltinTypes.Bool, loc), "enumType", 0, null, loc),
					},
					new [] {
						Compiler.BuiltinTypes.Object,
						Compiler.BuiltinTypes.Object,
						Compiler.BuiltinTypes.Bool
					});

				var m = new Method (this, new TypeExpression (Compiler.BuiltinTypes.Bool, loc),
					Modifiers.PUBLIC | Modifiers.STATIC | Modifiers.DEBUGGER_HIDDEN, new MemberName ("NumberMatcher", loc),
					parameters, null);

				parameters [0].Resolve (m, 0);
				parameters [1].Resolve (m, 1);
				parameters [2].Resolve (m, 2);

				ToplevelBlock top_block = new ToplevelBlock (Compiler, parameters, loc);
				m.Block = top_block;

				//
				// if (enumType)
				//		return Equals (obj, value);
				//
				var equals_args = new Arguments (2);
				equals_args.Add (new Argument (top_block.GetParameterReference (0, loc)));
				equals_args.Add (new Argument (top_block.GetParameterReference (1, loc)));

				var if_type = new If (
					              top_block.GetParameterReference (2, loc),
					              new Return (new Invocation (new SimpleName ("Equals", loc), equals_args), loc),
					              loc);

				top_block.AddStatement (if_type);

				//
				// if (obj is Enum || obj == null)
				//		return false;
				//

				var if_enum = new If (
					              new Binary (Binary.Operator.LogicalOr,
						              new Is (top_block.GetParameterReference (0, loc), new TypeExpression (Compiler.BuiltinTypes.Enum, loc), loc),
						              new Binary (Binary.Operator.Equality, top_block.GetParameterReference (0, loc), new NullLiteral (loc))),
					              new Return (new BoolLiteral (Compiler.BuiltinTypes, false, loc), loc),
					              loc);

				top_block.AddStatement (if_enum);


				var system_convert = new MemberAccess (new QualifiedAliasMember ("global", "System", loc), "Convert", loc);
				var expl_block = new ExplicitBlock (top_block, loc, loc);

				//
				// var converted = System.Convert.ChangeType (obj, System.Convert.GetTypeCode (value));
				//
				var lv_converted = LocalVariable.CreateCompilerGenerated (Compiler.BuiltinTypes.Object, top_block, loc);

				var arguments_gettypecode = new Arguments (1);
				arguments_gettypecode.Add (new Argument (top_block.GetParameterReference (1, loc)));

				var gettypecode = new Invocation (new MemberAccess (system_convert, "GetTypeCode", loc), arguments_gettypecode);

				var arguments_changetype = new Arguments (1);
				arguments_changetype.Add (new Argument (top_block.GetParameterReference (0, loc)));
				arguments_changetype.Add (new Argument (gettypecode));

				var changetype = new Invocation (new MemberAccess (system_convert, "ChangeType", loc), arguments_changetype);

				expl_block.AddStatement (new StatementExpression (new SimpleAssign (new LocalVariableReference (lv_converted, loc), changetype, loc)));


				//
				// return converted.Equals (value)
				//
				var equals_arguments = new Arguments (1);
				equals_arguments.Add (new Argument (top_block.GetParameterReference (1, loc)));
				var equals_invocation = new Invocation (new MemberAccess (new LocalVariableReference (lv_converted, loc), "Equals"), equals_arguments);
				expl_block.AddStatement (new Return (equals_invocation, loc));

				var catch_block = new ExplicitBlock (top_block, loc, loc);
				catch_block.AddStatement (new Return (new BoolLiteral (Compiler.BuiltinTypes, false, loc), loc));
				top_block.AddStatement (new TryCatch (expl_block, new List<Catch> () {
					new Catch (catch_block, loc)
				}, loc, false));

				m.Define ();
				m.PrepareEmit ();
				AddMember (m);

				return m;
			}

		//
		// Reformats this block to be top-level iterator block
		//
		public IteratorStorey ChangeToIterator (Iterator iterator, ToplevelBlock source)
		{
			IsIterator = true;

			// Creates block with original statements
			AddStatement (new IteratorStatement (iterator, new Block (this, source)));

			source.statements = new List<Statement> (1);
			source.AddStatement (new Return (iterator, iterator.Location));
			source.IsIterator = false;

			IteratorStorey iterator_storey = new IteratorStorey (iterator);
			source.am_storey = iterator_storey;
			return iterator_storey;
		}

			public BlockScopeExpression (Expression child, ToplevelBlock block)
			{
				this.child = child;
				this.block = block;
			}

		public ToplevelParameterInfo (ToplevelBlock block, int idx)
		{
			this.Block = block;
			this.Index = idx;
		}

		public void AddAnonymousChild (ToplevelBlock b)
		{
			if (anonymous_children == null)
				anonymous_children = new List<ToplevelBlock> ();

			anonymous_children.Add (b);
		}

		void CreateTypeParameters ()
		{
			var tparams = MemberName.TypeParameters;
			string[] snames = new string[MemberName.Arity];
			var parent_tparams = Parent.TypeParametersAll;

			for (int i = 0; i < snames.Length; i++) {
				string type_argument_name = tparams[i].MemberName.Name;

				if (block == null) {
					int idx = parameters.GetParameterIndexByName (type_argument_name);
					if (idx >= 0) {
						var b = block;
						if (b == null)
							b = new ToplevelBlock (Compiler, Location);

						b.Error_AlreadyDeclaredTypeParameter (type_argument_name, parameters[i].Location);
					}
				} else {
					INamedBlockVariable variable = null;
					block.GetLocalName (type_argument_name, block, ref variable);
					if (variable != null)
						variable.Block.Error_AlreadyDeclaredTypeParameter (type_argument_name, variable.Location);
				}

				if (parent_tparams != null) {
					var tp = parent_tparams.Find (type_argument_name);
					if (tp != null) {
						tparams[i].WarningParentNameConflict (tp);
					}
				}

				snames[i] = type_argument_name;
			}

			GenericTypeParameterBuilder[] gen_params = MethodBuilder.DefineGenericParameters (snames);
			tparams.Define (gen_params, null, 0, Parent);
		}

			public override void Emit (DeclSpace parent)
			{
				if ((method.ModFlags & (Modifiers.ABSTRACT | Modifiers.EXTERN)) == 0) {
					if (parent is Class) {
						MethodBuilder mb = method_data.MethodBuilder;
						mb.SetImplementationFlags (mb.GetMethodImplementationFlags () | MethodImplAttributes.Synchronized);
					}

					var field_info = ((EventField) method).backing_field;
					FieldExpr f_expr = new FieldExpr (field_info, Location);
					if ((method.ModFlags & Modifiers.STATIC) == 0)
						f_expr.InstanceExpression = new CompilerGeneratedThis (field_info.Spec.MemberType, Location);

					block = new ToplevelBlock (Compiler, ParameterInfo, Location);
					block.AddStatement (new StatementExpression (
						new CompoundAssign (Operation,
							f_expr,
							block.GetParameterReference (ParameterInfo[0].Name, Location),
							Location)));
				}

				base.Emit (parent);
			}

		protected virtual AnonymousMethodBody CompatibleMethodFactory (TypeSpec return_type, TypeSpec delegate_type, ParametersCompiled p, ToplevelBlock b)
		{
			return new AnonymousMethodBody (p, b, return_type, delegate_type, loc);
		}

        void Define_Current(bool is_generic)
        {
            TypeExpr type;

            MemberName name = new MemberName (QualifiedAliasMember.GlobalAlias, "System", null, Location);
            name = new MemberName (name, "Collections", Location);

            if (is_generic) {
                name = new MemberName (name, "Generic", Location);
                name = new MemberName (name, "IEnumerator", generic_args, Location);
                type = iterator_type_expr;
            } else {
                name = new MemberName (name, "IEnumerator");
                type = TypeManager.system_object_expr;
            }

            name = new MemberName (name, "Current", Location);

            ToplevelBlock get_block = new ToplevelBlock (Compiler, Location);
            get_block.AddStatement (new Return (new DynamicFieldExpr (CurrentField, Location), Location));

            Accessor getter = new Accessor (get_block, 0, null, null, Location);

            Property current = new Property (
                this, type, Modifiers.DEBUGGER_HIDDEN, name, null, getter, null, false);
            AddProperty (current);
        }

		protected AnonymousExpression (ToplevelBlock block, TypeSpec return_type, Location loc)
		{
			this.ReturnType = return_type;
			this.block = block;
			this.loc = loc;
		}

            public IteratorMethod(IteratorStorey host, FullNamedExpression returnType, Modifiers mod, MemberName name)
                : base(host, null, returnType, mod | Modifiers.DEBUGGER_HIDDEN | Modifiers.COMPILER_GENERATED,
				  name, ParametersCompiled.EmptyReadOnlyParameters, null)
            {
                this.host = host;

                Block = new ToplevelBlock (Compiler, host.Iterator.Container.Toplevel, ParametersCompiled.EmptyReadOnlyParameters, Location);
            }

		public AnonymousMethodBody (ParametersCompiled parameters,
					ToplevelBlock block, TypeSpec return_type, TypeSpec delegate_type,
					Location loc)
			: base (block, return_type, loc)
		{
			this.type = delegate_type;
			this.parameters = parameters;
		}