private BoundExpression BindAnonymousObjectCreation(AnonymousObjectCreationExpressionSyntax node, DiagnosticBag diagnostics) { // prepare var initializers = node.Initializers; int fieldCount = initializers.Count; bool hasError = false; // bind field initializers BoundExpression[] boundExpressions = new BoundExpression[fieldCount]; AnonymousTypeField[] fields = new AnonymousTypeField[fieldCount]; CSharpSyntaxNode[] fieldSyntaxNodes = new CSharpSyntaxNode[fieldCount]; // WARNING: Note that SemanticModel.GetDeclaredSymbol for field initializer node relies on // the fact that the order of properties in anonymous type template corresponds // 1-to-1 to the appropriate filed initializer syntax nodes; This means such // correspondence must be preserved all the time including erroneous scenarios // set of names already used var uniqueFieldNames = PooledHashSet <string> .GetInstance(); for (int i = 0; i < fieldCount; i++) { AnonymousObjectMemberDeclaratorSyntax fieldInitializer = initializers[i]; NameEqualsSyntax nameEquals = fieldInitializer.NameEquals; ExpressionSyntax expression = fieldInitializer.Expression; SyntaxToken nameToken = default(SyntaxToken); if (nameEquals != null) { nameToken = nameEquals.Name.Identifier; } else { if (!IsAnonymousTypeMemberExpression(expression)) { hasError = true; diagnostics.Add(ErrorCode.ERR_InvalidAnonymousTypeMemberDeclarator, expression.GetLocation()); } nameToken = expression.ExtractAnonymousTypeMemberName(); } hasError |= expression.HasErrors; boundExpressions[i] = this.BindValue(expression, diagnostics, BindValueKind.RValue); // check the name to be unique string fieldName = null; if (nameToken.Kind() == SyntaxKind.IdentifierToken) { fieldName = nameToken.ValueText; if (!uniqueFieldNames.Add(fieldName)) { // name duplication Error(diagnostics, ErrorCode.ERR_AnonymousTypeDuplicatePropertyName, fieldInitializer); hasError = true; fieldName = null; } } else { // there is something wrong with field's name hasError = true; } // calculate the expression's type and report errors if needed TypeSymbol fieldType = GetAnonymousTypeFieldType(boundExpressions[i], fieldInitializer, diagnostics, ref hasError); // build anonymous type field descriptor fieldSyntaxNodes[i] = (nameToken.Kind() == SyntaxKind.IdentifierToken) ? (CSharpSyntaxNode)nameToken.Parent : fieldInitializer; fields[i] = new AnonymousTypeField( fieldName == null ? "$" + i.ToString() : fieldName, fieldSyntaxNodes[i].Location, TypeWithAnnotations.Create(fieldType)); // NOTE: ERR_InvalidAnonymousTypeMemberDeclarator (CS0746) would be generated by parser if needed } uniqueFieldNames.Free(); // Create anonymous type AnonymousTypeManager manager = this.Compilation.AnonymousTypeManager; AnonymousTypeDescriptor descriptor = new AnonymousTypeDescriptor(fields.AsImmutableOrNull(), node.NewKeyword.GetLocation()); NamedTypeSymbol anonymousType = manager.ConstructAnonymousTypeSymbol(descriptor); // declarators - bound nodes created for providing semantic info // on anonymous type fields having explicitly specified name ArrayBuilder <BoundAnonymousPropertyDeclaration> declarators = ArrayBuilder <BoundAnonymousPropertyDeclaration> .GetInstance(); for (int i = 0; i < fieldCount; i++) { NameEqualsSyntax explicitName = initializers[i].NameEquals; if (explicitName != null) { AnonymousTypeField field = fields[i]; if (field.Name != null) { // get property symbol and create a bound property declaration node foreach (var symbol in anonymousType.GetMembers(field.Name)) { if (symbol.Kind == SymbolKind.Property) { declarators.Add(new BoundAnonymousPropertyDeclaration(fieldSyntaxNodes[i], (PropertySymbol)symbol, field.Type)); break; } } } } } // check if anonymous object creation is allowed in this context if (!this.IsAnonymousTypesAllowed()) { Error(diagnostics, ErrorCode.ERR_AnonymousTypeNotAvailable, node.NewKeyword); hasError = true; } // Finally create a bound node return(new BoundAnonymousObjectCreationExpression( node, anonymousType.InstanceConstructors[0], boundExpressions.AsImmutableOrNull(), declarators.ToImmutableAndFree(), anonymousType, hasError)); }