// 
// IAstVisitor.cs
//
// Author:
//       Mike Krüger <mkrueger@novell.com>
// 
// Copyright (c) 2010 Novell, Inc (http://www.novell.com)
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.


namespace ICSharpCode.Decompiler.CSharp.Syntax
{
	/// <summary>
	/// AST visitor with a default implementation that visits all node depth-first.
	/// </summary>
	public abstract class DepthFirstAstVisitor : IAstVisitor
	{
		protected virtual void VisitChildren(AstNode node)
		{
			AstNode? next;
			for (var child = node.FirstChild; child != null; child = next)
			{
				// Store next to allow the loop to continue
				// if the visitor removes/replaces child.
				next = child.NextSibling;
				child.AcceptVisitor(this);
			}
		}

		public virtual void VisitNullNode(AstNode nullNode)
		{
			// Should we call VisitChildren here?
			// We usually want to ignore null nodes.
			// Older NR versions (before VisitNullNode was introduced) didn't call VisitChildren() with null nodes;
			// so changing this might break VisitChildren() overrides that expect the node to be part of the AST.
		}

		public virtual void VisitSyntaxTree(SyntaxTree syntaxTree)
		{
			VisitChildren(syntaxTree);
		}

		public virtual void VisitComment(Comment comment)
		{
			VisitChildren(comment);
		}

		public virtual void VisitDocumentationReference(DocumentationReference documentationReference)
		{
			VisitChildren(documentationReference);
		}

		public virtual void VisitPreProcessorDirective(PreProcessorDirective preProcessorDirective)
		{
			VisitChildren(preProcessorDirective);
		}

		public virtual void VisitIdentifier(Identifier identifier)
		{
			VisitChildren(identifier);
		}

		public virtual void VisitCSharpTokenNode(CSharpTokenNode token)
		{
			VisitChildren(token);
		}

		public virtual void VisitPrimitiveType(PrimitiveType primitiveType)
		{
			VisitChildren(primitiveType);
		}

		public virtual void VisitComposedType(ComposedType composedType)
		{
			VisitChildren(composedType);
		}

		public virtual void VisitSimpleType(SimpleType simpleType)
		{
			VisitChildren(simpleType);
		}

		public virtual void VisitMemberType(MemberType memberType)
		{
			VisitChildren(memberType);
		}

		public virtual void VisitTupleType(TupleAstType tupleType)
		{
			VisitChildren(tupleType);
		}

		public virtual void VisitTupleTypeElement(TupleTypeElement tupleTypeElement)
		{
			VisitChildren(tupleTypeElement);
		}

		public virtual void VisitFunctionPointerType(FunctionPointerAstType functionPointerType)
		{
			VisitChildren(functionPointerType);
		}

		public virtual void VisitInvocationType(InvocationAstType invocationType)
		{
			VisitChildren(invocationType);
		}

		public virtual void VisitAttribute(Attribute attribute)
		{
			VisitChildren(attribute);
		}

		public virtual void VisitAttributeSection(AttributeSection attributeSection)
		{
			VisitChildren(attributeSection);
		}

		public virtual void VisitDelegateDeclaration(DelegateDeclaration delegateDeclaration)
		{
			VisitChildren(delegateDeclaration);
		}

		public virtual void VisitNamespaceDeclaration(NamespaceDeclaration namespaceDeclaration)
		{
			VisitChildren(namespaceDeclaration);
		}

		public virtual void VisitTypeDeclaration(TypeDeclaration typeDeclaration)
		{
			VisitChildren(typeDeclaration);
		}

		public virtual void VisitTypeParameterDeclaration(TypeParameterDeclaration typeParameterDeclaration)
		{
			VisitChildren(typeParameterDeclaration);
		}

		public virtual void VisitEnumMemberDeclaration(EnumMemberDeclaration enumMemberDeclaration)
		{
			VisitChildren(enumMemberDeclaration);
		}

		public virtual void VisitUsingDeclaration(UsingDeclaration usingDeclaration)
		{
			VisitChildren(usingDeclaration);
		}

		public virtual void VisitUsingAliasDeclaration(UsingAliasDeclaration usingDeclaration)
		{
			VisitChildren(usingDeclaration);
		}

		public virtual void VisitExternAliasDeclaration(ExternAliasDeclaration externAliasDeclaration)
		{
			VisitChildren(externAliasDeclaration);
		}

		public virtual void VisitConstructorDeclaration(ConstructorDeclaration constructorDeclaration)
		{
			VisitChildren(constructorDeclaration);
		}

		public virtual void VisitConstructorInitializer(ConstructorInitializer constructorInitializer)
		{
			VisitChildren(constructorInitializer);
		}

		public virtual void VisitDestructorDeclaration(DestructorDeclaration destructorDeclaration)
		{
			VisitChildren(destructorDeclaration);
		}

		public virtual void VisitEventDeclaration(EventDeclaration eventDeclaration)
		{
			VisitChildren(eventDeclaration);
		}

		public virtual void VisitCustomEventDeclaration(CustomEventDeclaration eventDeclaration)
		{
			VisitChildren(eventDeclaration);
		}

		public virtual void VisitFieldDeclaration(FieldDeclaration fieldDeclaration)
		{
			VisitChildren(fieldDeclaration);
		}

		public virtual void VisitFixedFieldDeclaration(FixedFieldDeclaration fixedFieldDeclaration)
		{
			VisitChildren(fixedFieldDeclaration);
		}

		public virtual void VisitFixedVariableInitializer(FixedVariableInitializer fixedVariableInitializer)
		{
			VisitChildren(fixedVariableInitializer);
		}

		public virtual void VisitIndexerDeclaration(IndexerDeclaration indexerDeclaration)
		{
			VisitChildren(indexerDeclaration);
		}

		public virtual void VisitMethodDeclaration(MethodDeclaration methodDeclaration)
		{
			VisitChildren(methodDeclaration);
		}

		public virtual void VisitOperatorDeclaration(OperatorDeclaration operatorDeclaration)
		{
			VisitChildren(operatorDeclaration);
		}

		public virtual void VisitPropertyDeclaration(PropertyDeclaration propertyDeclaration)
		{
			VisitChildren(propertyDeclaration);
		}

		public virtual void VisitAccessor(Accessor accessor)
		{
			VisitChildren(accessor);
		}

		public virtual void VisitVariableInitializer(VariableInitializer variableInitializer)
		{
			VisitChildren(variableInitializer);
		}

		public virtual void VisitParameterDeclaration(ParameterDeclaration parameterDeclaration)
		{
			VisitChildren(parameterDeclaration);
		}

		public virtual void VisitConstraint(Constraint constraint)
		{
			VisitChildren(constraint);
		}

		public virtual void VisitBlockStatement(BlockStatement blockStatement)
		{
			VisitChildren(blockStatement);
		}

		public virtual void VisitExpressionStatement(ExpressionStatement expressionStatement)
		{
			VisitChildren(expressionStatement);
		}

		public virtual void VisitBreakStatement(BreakStatement breakStatement)
		{
			VisitChildren(breakStatement);
		}

		public virtual void VisitCheckedStatement(CheckedStatement checkedStatement)
		{
			VisitChildren(checkedStatement);
		}

		public virtual void VisitContinueStatement(ContinueStatement continueStatement)
		{
			VisitChildren(continueStatement);
		}

		public virtual void VisitDoWhileStatement(DoWhileStatement doWhileStatement)
		{
			VisitChildren(doWhileStatement);
		}

		public virtual void VisitEmptyStatement(EmptyStatement emptyStatement)
		{
			VisitChildren(emptyStatement);
		}

		public virtual void VisitFixedStatement(FixedStatement fixedStatement)
		{
			VisitChildren(fixedStatement);
		}

		public virtual void VisitForeachStatement(ForeachStatement foreachStatement)
		{
			VisitChildren(foreachStatement);
		}

		public virtual void VisitForStatement(ForStatement forStatement)
		{
			VisitChildren(forStatement);
		}

		public virtual void VisitGotoCaseStatement(GotoCaseStatement gotoCaseStatement)
		{
			VisitChildren(gotoCaseStatement);
		}

		public virtual void VisitGotoDefaultStatement(GotoDefaultStatement gotoDefaultStatement)
		{
			VisitChildren(gotoDefaultStatement);
		}

		public virtual void VisitGotoStatement(GotoStatement gotoStatement)
		{
			VisitChildren(gotoStatement);
		}

		public virtual void VisitIfElseStatement(IfElseStatement ifElseStatement)
		{
			VisitChildren(ifElseStatement);
		}

		public virtual void VisitLabelStatement(LabelStatement labelStatement)
		{
			VisitChildren(labelStatement);
		}

		public virtual void VisitLockStatement(LockStatement lockStatement)
		{
			VisitChildren(lockStatement);
		}

		public virtual void VisitReturnStatement(ReturnStatement returnStatement)
		{
			VisitChildren(returnStatement);
		}

		public virtual void VisitSwitchStatement(SwitchStatement switchStatement)
		{
			VisitChildren(switchStatement);
		}

		public virtual void VisitSwitchSection(SwitchSection switchSection)
		{
			VisitChildren(switchSection);
		}

		public virtual void VisitCaseLabel(CaseLabel caseLabel)
		{
			VisitChildren(caseLabel);
		}

		public virtual void VisitSwitchExpression(SwitchExpression switchExpression)
		{
			VisitChildren(switchExpression);
		}

		public virtual void VisitSwitchExpressionSection(SwitchExpressionSection switchExpressionSection)
		{
			VisitChildren(switchExpressionSection);
		}

		public virtual void VisitThrowStatement(ThrowStatement throwStatement)
		{
			VisitChildren(throwStatement);
		}

		public virtual void VisitTryCatchStatement(TryCatchStatement tryCatchStatement)
		{
			VisitChildren(tryCatchStatement);
		}

		public virtual void VisitCatchClause(CatchClause catchClause)
		{
			VisitChildren(catchClause);
		}

		public virtual void VisitUncheckedStatement(UncheckedStatement uncheckedStatement)
		{
			VisitChildren(uncheckedStatement);
		}

		public virtual void VisitUnsafeStatement(UnsafeStatement unsafeStatement)
		{
			VisitChildren(unsafeStatement);
		}

		public virtual void VisitUsingStatement(UsingStatement usingStatement)
		{
			VisitChildren(usingStatement);
		}

		public virtual void VisitVariableDeclarationStatement(VariableDeclarationStatement variableDeclarationStatement)
		{
			VisitChildren(variableDeclarationStatement);
		}

		public virtual void VisitLocalFunctionDeclarationStatement(LocalFunctionDeclarationStatement localFunctionDeclarationStatement)
		{
			VisitChildren(localFunctionDeclarationStatement);
		}

		public virtual void VisitWhileStatement(WhileStatement whileStatement)
		{
			VisitChildren(whileStatement);
		}

		public virtual void VisitYieldBreakStatement(YieldBreakStatement yieldBreakStatement)
		{
			VisitChildren(yieldBreakStatement);
		}

		public virtual void VisitYieldReturnStatement(YieldReturnStatement yieldReturnStatement)
		{
			VisitChildren(yieldReturnStatement);
		}

		public virtual void VisitAnonymousMethodExpression(AnonymousMethodExpression anonymousMethodExpression)
		{
			VisitChildren(anonymousMethodExpression);
		}

		public virtual void VisitLambdaExpression(LambdaExpression lambdaExpression)
		{
			VisitChildren(lambdaExpression);
		}

		public virtual void VisitAssignmentExpression(AssignmentExpression assignmentExpression)
		{
			VisitChildren(assignmentExpression);
		}

		public virtual void VisitBaseReferenceExpression(BaseReferenceExpression baseReferenceExpression)
		{
			VisitChildren(baseReferenceExpression);
		}

		public virtual void VisitBinaryOperatorExpression(BinaryOperatorExpression binaryOperatorExpression)
		{
			VisitChildren(binaryOperatorExpression);
		}

		public virtual void VisitCastExpression(CastExpression castExpression)
		{
			VisitChildren(castExpression);
		}

		public virtual void VisitCheckedExpression(CheckedExpression checkedExpression)
		{
			VisitChildren(checkedExpression);
		}

		public virtual void VisitConditionalExpression(ConditionalExpression conditionalExpression)
		{
			VisitChildren(conditionalExpression);
		}

		public virtual void VisitIdentifierExpression(IdentifierExpression identifierExpression)
		{
			VisitChildren(identifierExpression);
		}

		public virtual void VisitIndexerExpression(IndexerExpression indexerExpression)
		{
			VisitChildren(indexerExpression);
		}

		public virtual void VisitInterpolatedStringExpression(InterpolatedStringExpression interpolatedStringExpression)
		{
			VisitChildren(interpolatedStringExpression);
		}

		public virtual void VisitInterpolation(Interpolation interpolation)
		{
			VisitChildren(interpolation);
		}

		public virtual void VisitInterpolatedStringText(InterpolatedStringText interpolatedStringText)
		{
			VisitChildren(interpolatedStringText);
		}

		public virtual void VisitInvocationExpression(InvocationExpression invocationExpression)
		{
			VisitChildren(invocationExpression);
		}

		public virtual void VisitDirectionExpression(DirectionExpression directionExpression)
		{
			VisitChildren(directionExpression);
		}

		public virtual void VisitMemberReferenceExpression(MemberReferenceExpression memberReferenceExpression)
		{
			VisitChildren(memberReferenceExpression);
		}

		public virtual void VisitNullReferenceExpression(NullReferenceExpression nullReferenceExpression)
		{
			VisitChildren(nullReferenceExpression);
		}

		public virtual void VisitObjectCreateExpression(ObjectCreateExpression objectCreateExpression)
		{
			VisitChildren(objectCreateExpression);
		}

		public virtual void VisitDeclarationExpression(DeclarationExpression declarationExpression)
		{
			VisitChildren(declarationExpression);
		}

		public virtual void VisitRecursivePatternExpression(RecursivePatternExpression recursivePatternExpression)
		{
			VisitChildren(recursivePatternExpression);
		}

		public virtual void VisitOutVarDeclarationExpression(OutVarDeclarationExpression outVarDeclarationExpression)
		{
			VisitChildren(outVarDeclarationExpression);
		}

		public virtual void VisitAnonymousTypeCreateExpression(AnonymousTypeCreateExpression anonymousTypeCreateExpression)
		{
			VisitChildren(anonymousTypeCreateExpression);
		}

		public virtual void VisitArrayCreateExpression(ArrayCreateExpression arrayCreateExpression)
		{
			VisitChildren(arrayCreateExpression);
		}

		public virtual void VisitParenthesizedExpression(ParenthesizedExpression parenthesizedExpression)
		{
			VisitChildren(parenthesizedExpression);
		}

		public virtual void VisitPointerReferenceExpression(PointerReferenceExpression pointerReferenceExpression)
		{
			VisitChildren(pointerReferenceExpression);
		}

		public virtual void VisitPrimitiveExpression(PrimitiveExpression primitiveExpression)
		{
			VisitChildren(primitiveExpression);
		}

		public virtual void VisitSizeOfExpression(SizeOfExpression sizeOfExpression)
		{
			VisitChildren(sizeOfExpression);
		}

		public virtual void VisitStackAllocExpression(StackAllocExpression stackAllocExpression)
		{
			VisitChildren(stackAllocExpression);
		}

		public virtual void VisitThisReferenceExpression(ThisReferenceExpression thisReferenceExpression)
		{
			VisitChildren(thisReferenceExpression);
		}

		public virtual void VisitThrowExpression(ThrowExpression throwExpression)
		{
			VisitChildren(throwExpression);
		}

		public virtual void VisitTupleExpression(TupleExpression tupleExpression)
		{
			VisitChildren(tupleExpression);
		}

		public virtual void VisitTypeOfExpression(TypeOfExpression typeOfExpression)
		{
			VisitChildren(typeOfExpression);
		}

		public virtual void VisitTypeReferenceExpression(TypeReferenceExpression typeReferenceExpression)
		{
			VisitChildren(typeReferenceExpression);
		}

		public virtual void VisitUnaryOperatorExpression(UnaryOperatorExpression unaryOperatorExpression)
		{
			VisitChildren(unaryOperatorExpression);
		}

		public virtual void VisitUncheckedExpression(UncheckedExpression uncheckedExpression)
		{
			VisitChildren(uncheckedExpression);
		}

		public virtual void VisitQueryExpression(QueryExpression queryExpression)
		{
			VisitChildren(queryExpression);
		}

		public virtual void VisitQueryContinuationClause(QueryContinuationClause queryContinuationClause)
		{
			VisitChildren(queryContinuationClause);
		}

		public virtual void VisitQueryFromClause(QueryFromClause queryFromClause)
		{
			VisitChildren(queryFromClause);
		}

		public virtual void VisitQueryLetClause(QueryLetClause queryLetClause)
		{
			VisitChildren(queryLetClause);
		}

		public virtual void VisitQueryWhereClause(QueryWhereClause queryWhereClause)
		{
			VisitChildren(queryWhereClause);
		}

		public virtual void VisitQueryJoinClause(QueryJoinClause queryJoinClause)
		{
			VisitChildren(queryJoinClause);
		}

		public virtual void VisitQueryOrderClause(QueryOrderClause queryOrderClause)
		{
			VisitChildren(queryOrderClause);
		}

		public virtual void VisitQueryOrdering(QueryOrdering queryOrdering)
		{
			VisitChildren(queryOrdering);
		}

		public virtual void VisitQuerySelectClause(QuerySelectClause querySelectClause)
		{
			VisitChildren(querySelectClause);
		}

		public virtual void VisitQueryGroupClause(QueryGroupClause queryGroupClause)
		{
			VisitChildren(queryGroupClause);
		}

		public virtual void VisitAsExpression(AsExpression asExpression)
		{
			VisitChildren(asExpression);
		}

		public virtual void VisitIsExpression(IsExpression isExpression)
		{
			VisitChildren(isExpression);
		}

		public virtual void VisitDefaultValueExpression(DefaultValueExpression defaultValueExpression)
		{
			VisitChildren(defaultValueExpression);
		}

		public virtual void VisitUndocumentedExpression(UndocumentedExpression undocumentedExpression)
		{
			VisitChildren(undocumentedExpression);
		}

		public virtual void VisitArrayInitializerExpression(ArrayInitializerExpression arrayInitializerExpression)
		{
			VisitChildren(arrayInitializerExpression);
		}

		public virtual void VisitArraySpecifier(ArraySpecifier arraySpecifier)
		{
			VisitChildren(arraySpecifier);
		}

		public virtual void VisitNamedArgumentExpression(NamedArgumentExpression namedArgumentExpression)
		{
			VisitChildren(namedArgumentExpression);
		}

		public virtual void VisitNamedExpression(NamedExpression namedExpression)
		{
			VisitChildren(namedExpression);
		}

		public virtual void VisitSingleVariableDesignation(SingleVariableDesignation singleVariableDesignation)
		{
			VisitChildren(singleVariableDesignation);
		}

		public virtual void VisitParenthesizedVariableDesignation(ParenthesizedVariableDesignation parenthesizedVariableDesignation)
		{
			VisitChildren(parenthesizedVariableDesignation);
		}

		public virtual void VisitErrorNode(AstNode errorNode)
		{
			VisitChildren(errorNode);
		}

		public virtual void VisitPatternPlaceholder(AstNode placeholder, PatternMatching.Pattern pattern)
		{
			VisitChildren(placeholder);
		}

		public virtual void VisitWithInitializerExpression(WithInitializerExpression withInitializerExpression)
		{
			VisitChildren(withInitializerExpression);
		}
	}

	/// <summary>
	/// AST visitor with a default implementation that visits all node depth-first.
	/// </summary>
	public abstract class DepthFirstAstVisitor<T> : IAstVisitor<T>
	{
		protected virtual T? VisitChildren(AstNode node)
		{
			AstNode? next;
			for (var child = node.FirstChild; child != null; child = next)
			{
				// Store next to allow the loop to continue
				// if the visitor removes/replaces child.
				next = child.NextSibling;
				child.AcceptVisitor(this);
			}
			return default(T);
		}

		public virtual T? VisitNullNode(AstNode nullNode)
		{
			// Should we call VisitChildren here?
			// We usually want to ignore null nodes.
			// Older NR versions (before VisitNullNode was introduced) didn't call VisitChildren() with null nodes;
			// so changing this might break VisitChildren() overrides that expect the node to be part of the AST.
			return default(T);
		}

		public virtual T VisitSyntaxTree(SyntaxTree unit)
		{
			return VisitChildren(unit);
		}

		public virtual T VisitComment(Comment comment)
		{
			return VisitChildren(comment);
		}

		public virtual T VisitDocumentationReference(DocumentationReference documentationReference)
		{
			return VisitChildren(documentationReference);
		}

		public virtual T VisitPreProcessorDirective(PreProcessorDirective preProcessorDirective)
		{
			return VisitChildren(preProcessorDirective);
		}

		public virtual T VisitIdentifier(Identifier identifier)
		{
			return VisitChildren(identifier);
		}

		public virtual T VisitCSharpTokenNode(CSharpTokenNode token)
		{
			return VisitChildren(token);
		}

		public virtual T VisitPrimitiveType(PrimitiveType primitiveType)
		{
			return VisitChildren(primitiveType);
		}

		public virtual T VisitComposedType(ComposedType composedType)
		{
			return VisitChildren(composedType);
		}

		public virtual T VisitSimpleType(SimpleType simpleType)
		{
			return VisitChildren(simpleType);
		}

		public virtual T VisitMemberType(MemberType memberType)
		{
			return VisitChildren(memberType);
		}

		public virtual T VisitTupleType(TupleAstType tupleType)
		{
			return VisitChildren(tupleType);
		}

		public virtual T VisitTupleTypeElement(TupleTypeElement tupleTypeElement)
		{
			return VisitChildren(tupleTypeElement);
		}

		public virtual T VisitFunctionPointerType(FunctionPointerAstType functionPointerType)
		{
			return VisitChildren(functionPointerType);
		}

		public virtual T VisitInvocationType(InvocationAstType invocationType)
		{
			return VisitChildren(invocationType);
		}

		public virtual T VisitAttribute(Attribute attribute)
		{
			return VisitChildren(attribute);
		}

		public virtual T VisitAttributeSection(AttributeSection attributeSection)
		{
			return VisitChildren(attributeSection);
		}

		public virtual T VisitDelegateDeclaration(DelegateDeclaration delegateDeclaration)
		{
			return VisitChildren(delegateDeclaration);
		}

		public virtual T VisitNamespaceDeclaration(NamespaceDeclaration namespaceDeclaration)
		{
			return VisitChildren(namespaceDeclaration);
		}

		public virtual T VisitTypeDeclaration(TypeDeclaration typeDeclaration)
		{
			return VisitChildren(typeDeclaration);
		}

		public virtual T VisitTypeParameterDeclaration(TypeParameterDeclaration typeParameterDeclaration)
		{
			return VisitChildren(typeParameterDeclaration);
		}

		public virtual T VisitEnumMemberDeclaration(EnumMemberDeclaration enumMemberDeclaration)
		{
			return VisitChildren(enumMemberDeclaration);
		}

		public virtual T VisitUsingDeclaration(UsingDeclaration usingDeclaration)
		{
			return VisitChildren(usingDeclaration);
		}

		public virtual T VisitUsingAliasDeclaration(UsingAliasDeclaration usingDeclaration)
		{
			return VisitChildren(usingDeclaration);
		}

		public virtual T VisitExternAliasDeclaration(ExternAliasDeclaration externAliasDeclaration)
		{
			return VisitChildren(externAliasDeclaration);
		}

		public virtual T VisitConstructorDeclaration(ConstructorDeclaration constructorDeclaration)
		{
			return VisitChildren(constructorDeclaration);
		}

		public virtual T VisitConstructorInitializer(ConstructorInitializer constructorInitializer)
		{
			return VisitChildren(constructorInitializer);
		}

		public virtual T VisitDestructorDeclaration(DestructorDeclaration destructorDeclaration)
		{
			return VisitChildren(destructorDeclaration);
		}

		public virtual T VisitEventDeclaration(EventDeclaration eventDeclaration)
		{
			return VisitChildren(eventDeclaration);
		}

		public virtual T VisitCustomEventDeclaration(CustomEventDeclaration eventDeclaration)
		{
			return VisitChildren(eventDeclaration);
		}

		public virtual T VisitFieldDeclaration(FieldDeclaration fieldDeclaration)
		{
			return VisitChildren(fieldDeclaration);
		}

		public virtual T VisitFixedFieldDeclaration(FixedFieldDeclaration fixedFieldDeclaration)
		{
			return VisitChildren(fixedFieldDeclaration);
		}

		public virtual T VisitFixedVariableInitializer(FixedVariableInitializer fixedVariableInitializer)
		{
			return VisitChildren(fixedVariableInitializer);
		}

		public virtual T VisitIndexerDeclaration(IndexerDeclaration indexerDeclaration)
		{
			return VisitChildren(indexerDeclaration);
		}

		public virtual T VisitMethodDeclaration(MethodDeclaration methodDeclaration)
		{
			return VisitChildren(methodDeclaration);
		}

		public virtual T VisitOperatorDeclaration(OperatorDeclaration operatorDeclaration)
		{
			return VisitChildren(operatorDeclaration);
		}

		public virtual T VisitPropertyDeclaration(PropertyDeclaration propertyDeclaration)
		{
			return VisitChildren(propertyDeclaration);
		}

		public virtual T VisitAccessor(Accessor accessor)
		{
			return VisitChildren(accessor);
		}

		public virtual T VisitVariableInitializer(VariableInitializer variableInitializer)
		{
			return VisitChildren(variableInitializer);
		}

		public virtual T VisitParameterDeclaration(ParameterDeclaration parameterDeclaration)
		{
			return VisitChildren(parameterDeclaration);
		}

		public virtual T VisitConstraint(Constraint constraint)
		{
			return VisitChildren(constraint);
		}

		public virtual T VisitBlockStatement(BlockStatement blockStatement)
		{
			return VisitChildren(blockStatement);
		}

		public virtual T VisitExpressionStatement(ExpressionStatement expressionStatement)
		{
			return VisitChildren(expressionStatement);
		}

		public virtual T VisitBreakStatement(BreakStatement breakStatement)
		{
			return VisitChildren(breakStatement);
		}

		public virtual T VisitCheckedStatement(CheckedStatement checkedStatement)
		{
			return VisitChildren(checkedStatement);
		}

		public virtual T VisitContinueStatement(ContinueStatement continueStatement)
		{
			return VisitChildren(continueStatement);
		}

		public virtual T VisitDoWhileStatement(DoWhileStatement doWhileStatement)
		{
			return VisitChildren(doWhileStatement);
		}

		public virtual T VisitEmptyStatement(EmptyStatement emptyStatement)
		{
			return VisitChildren(emptyStatement);
		}

		public virtual T VisitFixedStatement(FixedStatement fixedStatement)
		{
			return VisitChildren(fixedStatement);
		}

		public virtual T VisitForeachStatement(ForeachStatement foreachStatement)
		{
			return VisitChildren(foreachStatement);
		}

		public virtual T VisitForStatement(ForStatement forStatement)
		{
			return VisitChildren(forStatement);
		}

		public virtual T VisitGotoCaseStatement(GotoCaseStatement gotoCaseStatement)
		{
			return VisitChildren(gotoCaseStatement);
		}

		public virtual T VisitGotoDefaultStatement(GotoDefaultStatement gotoDefaultStatement)
		{
			return VisitChildren(gotoDefaultStatement);
		}

		public virtual T VisitGotoStatement(GotoStatement gotoStatement)
		{
			return VisitChildren(gotoStatement);
		}

		public virtual T VisitIfElseStatement(IfElseStatement ifElseStatement)
		{
			return VisitChildren(ifElseStatement);
		}

		public virtual T VisitLabelStatement(LabelStatement labelStatement)
		{
			return VisitChildren(labelStatement);
		}

		public virtual T VisitLockStatement(LockStatement lockStatement)
		{
			return VisitChildren(lockStatement);
		}

		public virtual T VisitReturnStatement(ReturnStatement returnStatement)
		{
			return VisitChildren(returnStatement);
		}

		public virtual T VisitSwitchStatement(SwitchStatement switchStatement)
		{
			return VisitChildren(switchStatement);
		}

		public virtual T VisitSwitchSection(SwitchSection switchSection)
		{
			return VisitChildren(switchSection);
		}

		public virtual T VisitCaseLabel(CaseLabel caseLabel)
		{
			return VisitChildren(caseLabel);
		}

		public virtual T VisitSwitchExpression(SwitchExpression switchExpression)
		{
			return VisitChildren(switchExpression);
		}

		public virtual T VisitSwitchExpressionSection(SwitchExpressionSection switchExpressionSection)
		{
			return VisitChildren(switchExpressionSection);
		}

		public virtual T VisitThrowStatement(ThrowStatement throwStatement)
		{
			return VisitChildren(throwStatement);
		}

		public virtual T VisitTryCatchStatement(TryCatchStatement tryCatchStatement)
		{
			return VisitChildren(tryCatchStatement);
		}

		public virtual T VisitCatchClause(CatchClause catchClause)
		{
			return VisitChildren(catchClause);
		}

		public virtual T VisitUncheckedStatement(UncheckedStatement uncheckedStatement)
		{
			return VisitChildren(uncheckedStatement);
		}

		public virtual T VisitUnsafeStatement(UnsafeStatement unsafeStatement)
		{
			return VisitChildren(unsafeStatement);
		}

		public virtual T VisitUsingStatement(UsingStatement usingStatement)
		{
			return VisitChildren(usingStatement);
		}

		public virtual T VisitVariableDeclarationStatement(VariableDeclarationStatement variableDeclarationStatement)
		{
			return VisitChildren(variableDeclarationStatement);
		}

		public virtual T VisitLocalFunctionDeclarationStatement(LocalFunctionDeclarationStatement localFunctionDeclarationStatement)
		{
			return VisitChildren(localFunctionDeclarationStatement);
		}

		public virtual T VisitWhileStatement(WhileStatement whileStatement)
		{
			return VisitChildren(whileStatement);
		}

		public virtual T VisitYieldBreakStatement(YieldBreakStatement yieldBreakStatement)
		{
			return VisitChildren(yieldBreakStatement);
		}

		public virtual T VisitYieldReturnStatement(YieldReturnStatement yieldReturnStatement)
		{
			return VisitChildren(yieldReturnStatement);
		}

		public virtual T VisitAnonymousMethodExpression(AnonymousMethodExpression anonymousMethodExpression)
		{
			return VisitChildren(anonymousMethodExpression);
		}

		public virtual T VisitLambdaExpression(LambdaExpression lambdaExpression)
		{
			return VisitChildren(lambdaExpression);
		}

		public virtual T VisitAssignmentExpression(AssignmentExpression assignmentExpression)
		{
			return VisitChildren(assignmentExpression);
		}

		public virtual T VisitBaseReferenceExpression(BaseReferenceExpression baseReferenceExpression)
		{
			return VisitChildren(baseReferenceExpression);
		}

		public virtual T VisitBinaryOperatorExpression(BinaryOperatorExpression binaryOperatorExpression)
		{
			return VisitChildren(binaryOperatorExpression);
		}

		public virtual T VisitCastExpression(CastExpression castExpression)
		{
			return VisitChildren(castExpression);
		}

		public virtual T VisitCheckedExpression(CheckedExpression checkedExpression)
		{
			return VisitChildren(checkedExpression);
		}

		public virtual T VisitConditionalExpression(ConditionalExpression conditionalExpression)
		{
			return VisitChildren(conditionalExpression);
		}

		public virtual T VisitIdentifierExpression(IdentifierExpression identifierExpression)
		{
			return VisitChildren(identifierExpression);
		}

		public virtual T VisitIndexerExpression(IndexerExpression indexerExpression)
		{
			return VisitChildren(indexerExpression);
		}

		public virtual T VisitInterpolatedStringExpression(InterpolatedStringExpression interpolatedStringExpression)
		{
			return VisitChildren(interpolatedStringExpression);
		}

		public virtual T VisitInterpolation(Interpolation interpolation)
		{
			return VisitChildren(interpolation);
		}

		public virtual T VisitInterpolatedStringText(InterpolatedStringText interpolatedStringText)
		{
			return VisitChildren(interpolatedStringText);
		}

		public virtual T VisitInvocationExpression(InvocationExpression invocationExpression)
		{
			return VisitChildren(invocationExpression);
		}

		public virtual T VisitDirectionExpression(DirectionExpression directionExpression)
		{
			return VisitChildren(directionExpression);
		}

		public virtual T VisitMemberReferenceExpression(MemberReferenceExpression memberReferenceExpression)
		{
			return VisitChildren(memberReferenceExpression);
		}

		public virtual T VisitNullReferenceExpression(NullReferenceExpression nullReferenceExpression)
		{
			return VisitChildren(nullReferenceExpression);
		}

		public virtual T VisitObjectCreateExpression(ObjectCreateExpression objectCreateExpression)
		{
			return VisitChildren(objectCreateExpression);
		}

		public virtual T VisitDeclarationExpression(DeclarationExpression declarationExpression)
		{
			return VisitChildren(declarationExpression);
		}

		public virtual T VisitRecursivePatternExpression(RecursivePatternExpression recursivePatternExpression)
		{
			return VisitChildren(recursivePatternExpression);
		}

		public virtual T VisitOutVarDeclarationExpression(OutVarDeclarationExpression outVarDeclarationExpression)
		{
			return VisitChildren(outVarDeclarationExpression);
		}

		public virtual T VisitAnonymousTypeCreateExpression(AnonymousTypeCreateExpression anonymousTypeCreateExpression)
		{
			return VisitChildren(anonymousTypeCreateExpression);
		}

		public virtual T VisitArrayCreateExpression(ArrayCreateExpression arrayCreateExpression)
		{
			return VisitChildren(arrayCreateExpression);
		}

		public virtual T VisitParenthesizedExpression(ParenthesizedExpression parenthesizedExpression)
		{
			return VisitChildren(parenthesizedExpression);
		}

		public virtual T VisitPointerReferenceExpression(PointerReferenceExpression pointerReferenceExpression)
		{
			return VisitChildren(pointerReferenceExpression);
		}

		public virtual T VisitPrimitiveExpression(PrimitiveExpression primitiveExpression)
		{
			return VisitChildren(primitiveExpression);
		}

		public virtual T VisitSizeOfExpression(SizeOfExpression sizeOfExpression)
		{
			return VisitChildren(sizeOfExpression);
		}

		public virtual T VisitStackAllocExpression(StackAllocExpression stackAllocExpression)
		{
			return VisitChildren(stackAllocExpression);
		}

		public virtual T VisitThisReferenceExpression(ThisReferenceExpression thisReferenceExpression)
		{
			return VisitChildren(thisReferenceExpression);
		}

		public virtual T VisitThrowExpression(ThrowExpression throwExpression)
		{
			return VisitChildren(throwExpression);
		}

		public virtual T VisitTupleExpression(TupleExpression tupleExpression)
		{
			return VisitChildren(tupleExpression);
		}

		public virtual T VisitTypeOfExpression(TypeOfExpression typeOfExpression)
		{
			return VisitChildren(typeOfExpression);
		}

		public virtual T VisitTypeReferenceExpression(TypeReferenceExpression typeReferenceExpression)
		{
			return VisitChildren(typeReferenceExpression);
		}

		public virtual T VisitUnaryOperatorExpression(UnaryOperatorExpression unaryOperatorExpression)
		{
			return VisitChildren(unaryOperatorExpression);
		}

		public virtual T VisitUncheckedExpression(UncheckedExpression uncheckedExpression)
		{
			return VisitChildren(uncheckedExpression);
		}

		public virtual T VisitQueryExpression(QueryExpression queryExpression)
		{
			return VisitChildren(queryExpression);
		}

		public virtual T VisitQueryContinuationClause(QueryContinuationClause queryContinuationClause)
		{
			return VisitChildren(queryContinuationClause);
		}

		public virtual T VisitQueryFromClause(QueryFromClause queryFromClause)
		{
			return VisitChildren(queryFromClause);
		}

		public virtual T VisitQueryLetClause(QueryLetClause queryLetClause)
		{
			return VisitChildren(queryLetClause);
		}

		public virtual T VisitQueryWhereClause(QueryWhereClause queryWhereClause)
		{
			return VisitChildren(queryWhereClause);
		}

		public virtual T VisitQueryJoinClause(QueryJoinClause queryJoinClause)
		{
			return VisitChildren(queryJoinClause);
		}

		public virtual T VisitQueryOrderClause(QueryOrderClause queryOrderClause)
		{
			return VisitChildren(queryOrderClause);
		}

		public virtual T VisitQueryOrdering(QueryOrdering queryOrdering)
		{
			return VisitChildren(queryOrdering);
		}

		public virtual T VisitQuerySelectClause(QuerySelectClause querySelectClause)
		{
			return VisitChildren(querySelectClause);
		}

		public virtual T VisitQueryGroupClause(QueryGroupClause queryGroupClause)
		{
			return VisitChildren(queryGroupClause);
		}

		public virtual T VisitAsExpression(AsExpression asExpression)
		{
			return VisitChildren(asExpression);
		}

		public virtual T VisitIsExpression(IsExpression isExpression)
		{
			return VisitChildren(isExpression);
		}

		public virtual T VisitDefaultValueExpression(DefaultValueExpression defaultValueExpression)
		{
			return VisitChildren(defaultValueExpression);
		}

		public virtual T VisitUndocumentedExpression(UndocumentedExpression undocumentedExpression)
		{
			return VisitChildren(undocumentedExpression);
		}

		public virtual T VisitArrayInitializerExpression(ArrayInitializerExpression arrayInitializerExpression)
		{
			return VisitChildren(arrayInitializerExpression);
		}

		public virtual T VisitArraySpecifier(ArraySpecifier arraySpecifier)
		{
			return VisitChildren(arraySpecifier);
		}

		public virtual T VisitNamedArgumentExpression(NamedArgumentExpression namedArgumentExpression)
		{
			return VisitChildren(namedArgumentExpression);
		}

		public virtual T VisitNamedExpression(NamedExpression namedExpression)
		{
			return VisitChildren(namedExpression);
		}

		public virtual T VisitSingleVariableDesignation(SingleVariableDesignation singleVariableDesignation)
		{
			return VisitChildren(singleVariableDesignation);
		}

		public virtual T VisitParenthesizedVariableDesignation(ParenthesizedVariableDesignation parenthesizedVariableDesignation)
		{
			return VisitChildren(parenthesizedVariableDesignation);
		}

		public virtual T VisitErrorNode(AstNode errorNode)
		{
			return VisitChildren(errorNode);
		}

		public virtual T VisitPatternPlaceholder(AstNode placeholder, PatternMatching.Pattern pattern)
		{
			return VisitChildren(placeholder);
		}

		public virtual T VisitWithInitializerExpression(WithInitializerExpression withInitializerExpression)
		{
			return VisitChildren(withInitializerExpression);
		}
	}

	/// <summary>
	/// AST visitor with a default implementation that visits all node depth-first.
	/// </summary>
	public abstract class DepthFirstAstVisitor<T, S> : IAstVisitor<T, S>
	{
		protected virtual S? VisitChildren(AstNode node, T data)
		{
			AstNode? next;
			for (var child = node.FirstChild; child != null; child = next)
			{
				// Store next to allow the loop to continue
				// if the visitor removes/replaces child.
				next = child.NextSibling;
				child.AcceptVisitor(this, data);
			}
			return default(S);
		}

		public virtual S? VisitNullNode(AstNode nullNode, T data)
		{
			// Should we call VisitChildren here?
			// We usually want to ignore null nodes.
			// Older NR versions (before VisitNullNode was introduced) didn't call VisitChildren() with null nodes;
			// so changing this might break VisitChildren() overrides that expect the node to be part of the AST.
			return default(S);
		}

		public virtual S? VisitSyntaxTree(SyntaxTree unit, T data)
		{
			return VisitChildren(unit, data);
		}

		public virtual S? VisitComment(Comment comment, T data)
		{
			return VisitChildren(comment, data);
		}

		public virtual S? VisitDocumentationReference(DocumentationReference documentationReference, T data)
		{
			return VisitChildren(documentationReference, data);
		}

		public virtual S? VisitPreProcessorDirective(PreProcessorDirective preProcessorDirective, T data)
		{
			return VisitChildren(preProcessorDirective, data);
		}

		public virtual S? VisitIdentifier(Identifier identifier, T data)
		{
			return VisitChildren(identifier, data);
		}

		public virtual S? VisitCSharpTokenNode(CSharpTokenNode token, T data)
		{
			return VisitChildren(token, data);
		}

		public virtual S? VisitPrimitiveType(PrimitiveType primitiveType, T data)
		{
			return VisitChildren(primitiveType, data);
		}

		public virtual S? VisitComposedType(ComposedType composedType, T data)
		{
			return VisitChildren(composedType, data);
		}

		public virtual S? VisitSimpleType(SimpleType simpleType, T data)
		{
			return VisitChildren(simpleType, data);
		}

		public virtual S? VisitMemberType(MemberType memberType, T data)
		{
			return VisitChildren(memberType, data);
		}

		public virtual S? VisitTupleType(TupleAstType tupleType, T data)
		{
			return VisitChildren(tupleType, data);
		}

		public virtual S? VisitTupleTypeElement(TupleTypeElement tupleTypeElement, T data)
		{
			return VisitChildren(tupleTypeElement, data);
		}

		public virtual S? VisitFunctionPointerType(FunctionPointerAstType functionPointerType, T data)
		{
			return VisitChildren(functionPointerType, data);
		}

		public virtual S? VisitInvocationType(InvocationAstType invocationType, T data)
		{
			return VisitChildren(invocationType, data);
		}

		public virtual S? VisitAttribute(Attribute attribute, T data)
		{
			return VisitChildren(attribute, data);
		}

		public virtual S? VisitAttributeSection(AttributeSection attributeSection, T data)
		{
			return VisitChildren(attributeSection, data);
		}

		public virtual S? VisitDelegateDeclaration(DelegateDeclaration delegateDeclaration, T data)
		{
			return VisitChildren(delegateDeclaration, data);
		}

		public virtual S? VisitNamespaceDeclaration(NamespaceDeclaration namespaceDeclaration, T data)
		{
			return VisitChildren(namespaceDeclaration, data);
		}

		public virtual S? VisitTypeDeclaration(TypeDeclaration typeDeclaration, T data)
		{
			return VisitChildren(typeDeclaration, data);
		}

		public virtual S? VisitTypeParameterDeclaration(TypeParameterDeclaration typeParameterDeclaration, T data)
		{
			return VisitChildren(typeParameterDeclaration, data);
		}

		public virtual S? VisitEnumMemberDeclaration(EnumMemberDeclaration enumMemberDeclaration, T data)
		{
			return VisitChildren(enumMemberDeclaration, data);
		}

		public virtual S? VisitUsingDeclaration(UsingDeclaration usingDeclaration, T data)
		{
			return VisitChildren(usingDeclaration, data);
		}

		public virtual S? VisitUsingAliasDeclaration(UsingAliasDeclaration usingDeclaration, T data)
		{
			return VisitChildren(usingDeclaration, data);
		}

		public virtual S? VisitExternAliasDeclaration(ExternAliasDeclaration externAliasDeclaration, T data)
		{
			return VisitChildren(externAliasDeclaration, data);
		}

		public virtual S? VisitConstructorDeclaration(ConstructorDeclaration constructorDeclaration, T data)
		{
			return VisitChildren(constructorDeclaration, data);
		}

		public virtual S? VisitConstructorInitializer(ConstructorInitializer constructorInitializer, T data)
		{
			return VisitChildren(constructorInitializer, data);
		}

		public virtual S? VisitDestructorDeclaration(DestructorDeclaration destructorDeclaration, T data)
		{
			return VisitChildren(destructorDeclaration, data);
		}

		public virtual S? VisitEventDeclaration(EventDeclaration eventDeclaration, T data)
		{
			return VisitChildren(eventDeclaration, data);
		}

		public virtual S? VisitCustomEventDeclaration(CustomEventDeclaration eventDeclaration, T data)
		{
			return VisitChildren(eventDeclaration, data);
		}

		public virtual S? VisitFieldDeclaration(FieldDeclaration fieldDeclaration, T data)
		{
			return VisitChildren(fieldDeclaration, data);
		}

		public virtual S? VisitFixedFieldDeclaration(FixedFieldDeclaration fixedFieldDeclaration, T data)
		{
			return VisitChildren(fixedFieldDeclaration, data);
		}

		public virtual S? VisitFixedVariableInitializer(FixedVariableInitializer fixedVariableInitializer, T data)
		{
			return VisitChildren(fixedVariableInitializer, data);
		}

		public virtual S? VisitIndexerDeclaration(IndexerDeclaration indexerDeclaration, T data)
		{
			return VisitChildren(indexerDeclaration, data);
		}

		public virtual S? VisitMethodDeclaration(MethodDeclaration methodDeclaration, T data)
		{
			return VisitChildren(methodDeclaration, data);
		}

		public virtual S? VisitOperatorDeclaration(OperatorDeclaration operatorDeclaration, T data)
		{
			return VisitChildren(operatorDeclaration, data);
		}

		public virtual S? VisitPropertyDeclaration(PropertyDeclaration propertyDeclaration, T data)
		{
			return VisitChildren(propertyDeclaration, data);
		}

		public virtual S? VisitAccessor(Accessor accessor, T data)
		{
			return VisitChildren(accessor, data);
		}

		public virtual S? VisitVariableInitializer(VariableInitializer variableInitializer, T data)
		{
			return VisitChildren(variableInitializer, data);
		}

		public virtual S? VisitParameterDeclaration(ParameterDeclaration parameterDeclaration, T data)
		{
			return VisitChildren(parameterDeclaration, data);
		}

		public virtual S? VisitConstraint(Constraint constraint, T data)
		{
			return VisitChildren(constraint, data);
		}

		public virtual S? VisitBlockStatement(BlockStatement blockStatement, T data)
		{
			return VisitChildren(blockStatement, data);
		}

		public virtual S? VisitExpressionStatement(ExpressionStatement expressionStatement, T data)
		{
			return VisitChildren(expressionStatement, data);
		}

		public virtual S? VisitBreakStatement(BreakStatement breakStatement, T data)
		{
			return VisitChildren(breakStatement, data);
		}

		public virtual S? VisitCheckedStatement(CheckedStatement checkedStatement, T data)
		{
			return VisitChildren(checkedStatement, data);
		}

		public virtual S? VisitContinueStatement(ContinueStatement continueStatement, T data)
		{
			return VisitChildren(continueStatement, data);
		}

		public virtual S? VisitDoWhileStatement(DoWhileStatement doWhileStatement, T data)
		{
			return VisitChildren(doWhileStatement, data);
		}

		public virtual S? VisitEmptyStatement(EmptyStatement emptyStatement, T data)
		{
			return VisitChildren(emptyStatement, data);
		}

		public virtual S? VisitFixedStatement(FixedStatement fixedStatement, T data)
		{
			return VisitChildren(fixedStatement, data);
		}

		public virtual S? VisitForeachStatement(ForeachStatement foreachStatement, T data)
		{
			return VisitChildren(foreachStatement, data);
		}

		public virtual S? VisitForStatement(ForStatement forStatement, T data)
		{
			return VisitChildren(forStatement, data);
		}

		public virtual S? VisitGotoCaseStatement(GotoCaseStatement gotoCaseStatement, T data)
		{
			return VisitChildren(gotoCaseStatement, data);
		}

		public virtual S? VisitGotoDefaultStatement(GotoDefaultStatement gotoDefaultStatement, T data)
		{
			return VisitChildren(gotoDefaultStatement, data);
		}

		public virtual S? VisitGotoStatement(GotoStatement gotoStatement, T data)
		{
			return VisitChildren(gotoStatement, data);
		}

		public virtual S? VisitIfElseStatement(IfElseStatement ifElseStatement, T data)
		{
			return VisitChildren(ifElseStatement, data);
		}

		public virtual S? VisitLabelStatement(LabelStatement labelStatement, T data)
		{
			return VisitChildren(labelStatement, data);
		}

		public virtual S? VisitLockStatement(LockStatement lockStatement, T data)
		{
			return VisitChildren(lockStatement, data);
		}

		public virtual S? VisitReturnStatement(ReturnStatement returnStatement, T data)
		{
			return VisitChildren(returnStatement, data);
		}

		public virtual S? VisitSwitchStatement(SwitchStatement switchStatement, T data)
		{
			return VisitChildren(switchStatement, data);
		}

		public virtual S? VisitSwitchSection(SwitchSection switchSection, T data)
		{
			return VisitChildren(switchSection, data);
		}

		public virtual S? VisitCaseLabel(CaseLabel caseLabel, T data)
		{
			return VisitChildren(caseLabel, data);
		}

		public virtual S? VisitSwitchExpression(SwitchExpression switchExpression, T data)
		{
			return VisitChildren(switchExpression, data);
		}

		public virtual S? VisitSwitchExpressionSection(SwitchExpressionSection switchExpressionSection, T data)
		{
			return VisitChildren(switchExpressionSection, data);
		}

		public virtual S? VisitThrowStatement(ThrowStatement throwStatement, T data)
		{
			return VisitChildren(throwStatement, data);
		}

		public virtual S? VisitTryCatchStatement(TryCatchStatement tryCatchStatement, T data)
		{
			return VisitChildren(tryCatchStatement, data);
		}

		public virtual S? VisitCatchClause(CatchClause catchClause, T data)
		{
			return VisitChildren(catchClause, data);
		}

		public virtual S? VisitUncheckedStatement(UncheckedStatement uncheckedStatement, T data)
		{
			return VisitChildren(uncheckedStatement, data);
		}

		public virtual S? VisitUnsafeStatement(UnsafeStatement unsafeStatement, T data)
		{
			return VisitChildren(unsafeStatement, data);
		}

		public virtual S? VisitUsingStatement(UsingStatement usingStatement, T data)
		{
			return VisitChildren(usingStatement, data);
		}

		public virtual S? VisitVariableDeclarationStatement(VariableDeclarationStatement variableDeclarationStatement, T data)
		{
			return VisitChildren(variableDeclarationStatement, data);
		}

		public virtual S? VisitLocalFunctionDeclarationStatement(LocalFunctionDeclarationStatement localFunctionDeclarationStatement, T data)
		{
			return VisitChildren(localFunctionDeclarationStatement, data);
		}

		public virtual S? VisitWhileStatement(WhileStatement whileStatement, T data)
		{
			return VisitChildren(whileStatement, data);
		}

		public virtual S? VisitYieldBreakStatement(YieldBreakStatement yieldBreakStatement, T data)
		{
			return VisitChildren(yieldBreakStatement, data);
		}

		public virtual S? VisitYieldReturnStatement(YieldReturnStatement yieldReturnStatement, T data)
		{
			return VisitChildren(yieldReturnStatement, data);
		}

		public virtual S? VisitAnonymousMethodExpression(AnonymousMethodExpression anonymousMethodExpression, T data)
		{
			return VisitChildren(anonymousMethodExpression, data);
		}

		public virtual S? VisitLambdaExpression(LambdaExpression lambdaExpression, T data)
		{
			return VisitChildren(lambdaExpression, data);
		}

		public virtual S? VisitAssignmentExpression(AssignmentExpression assignmentExpression, T data)
		{
			return VisitChildren(assignmentExpression, data);
		}

		public virtual S? VisitBaseReferenceExpression(BaseReferenceExpression baseReferenceExpression, T data)
		{
			return VisitChildren(baseReferenceExpression, data);
		}

		public virtual S? VisitBinaryOperatorExpression(BinaryOperatorExpression binaryOperatorExpression, T data)
		{
			return VisitChildren(binaryOperatorExpression, data);
		}

		public virtual S? VisitCastExpression(CastExpression castExpression, T data)
		{
			return VisitChildren(castExpression, data);
		}

		public virtual S? VisitCheckedExpression(CheckedExpression checkedExpression, T data)
		{
			return VisitChildren(checkedExpression, data);
		}

		public virtual S? VisitConditionalExpression(ConditionalExpression conditionalExpression, T data)
		{
			return VisitChildren(conditionalExpression, data);
		}

		public virtual S? VisitIdentifierExpression(IdentifierExpression identifierExpression, T data)
		{
			return VisitChildren(identifierExpression, data);
		}

		public virtual S? VisitIndexerExpression(IndexerExpression indexerExpression, T data)
		{
			return VisitChildren(indexerExpression, data);
		}

		public virtual S? VisitInterpolatedStringExpression(InterpolatedStringExpression interpolatedStringExpression, T data)
		{
			return VisitChildren(interpolatedStringExpression, data);
		}

		public virtual S? VisitInterpolation(Interpolation interpolation, T data)
		{
			return VisitChildren(interpolation, data);
		}

		public virtual S? VisitInterpolatedStringText(InterpolatedStringText interpolatedStringText, T data)
		{
			return VisitChildren(interpolatedStringText, data);
		}

		public virtual S? VisitInvocationExpression(InvocationExpression invocationExpression, T data)
		{
			return VisitChildren(invocationExpression, data);
		}

		public virtual S? VisitDirectionExpression(DirectionExpression directionExpression, T data)
		{
			return VisitChildren(directionExpression, data);
		}

		public virtual S? VisitMemberReferenceExpression(MemberReferenceExpression memberReferenceExpression, T data)
		{
			return VisitChildren(memberReferenceExpression, data);
		}

		public virtual S? VisitNullReferenceExpression(NullReferenceExpression nullReferenceExpression, T data)
		{
			return VisitChildren(nullReferenceExpression, data);
		}

		public virtual S? VisitObjectCreateExpression(ObjectCreateExpression objectCreateExpression, T data)
		{
			return VisitChildren(objectCreateExpression, data);
		}

		public virtual S? VisitDeclarationExpression(DeclarationExpression declarationExpression, T data)
		{
			return VisitChildren(declarationExpression, data);
		}

		public virtual S? VisitRecursivePatternExpression(RecursivePatternExpression recursivePatternExpression, T data)
		{
			return VisitChildren(recursivePatternExpression, data);
		}

		public virtual S? VisitOutVarDeclarationExpression(OutVarDeclarationExpression outVarDeclarationExpression, T data)
		{
			return VisitChildren(outVarDeclarationExpression, data);
		}

		public virtual S? VisitAnonymousTypeCreateExpression(AnonymousTypeCreateExpression anonymousTypeCreateExpression, T data)
		{
			return VisitChildren(anonymousTypeCreateExpression, data);
		}

		public virtual S? VisitArrayCreateExpression(ArrayCreateExpression arrayCreateExpression, T data)
		{
			return VisitChildren(arrayCreateExpression, data);
		}

		public virtual S? VisitParenthesizedExpression(ParenthesizedExpression parenthesizedExpression, T data)
		{
			return VisitChildren(parenthesizedExpression, data);
		}

		public virtual S? VisitPointerReferenceExpression(PointerReferenceExpression pointerReferenceExpression, T data)
		{
			return VisitChildren(pointerReferenceExpression, data);
		}

		public virtual S? VisitPrimitiveExpression(PrimitiveExpression primitiveExpression, T data)
		{
			return VisitChildren(primitiveExpression, data);
		}

		public virtual S? VisitSizeOfExpression(SizeOfExpression sizeOfExpression, T data)
		{
			return VisitChildren(sizeOfExpression, data);
		}

		public virtual S? VisitStackAllocExpression(StackAllocExpression stackAllocExpression, T data)
		{
			return VisitChildren(stackAllocExpression, data);
		}

		public virtual S? VisitThisReferenceExpression(ThisReferenceExpression thisReferenceExpression, T data)
		{
			return VisitChildren(thisReferenceExpression, data);
		}

		public virtual S? VisitThrowExpression(ThrowExpression throwExpression, T data)
		{
			return VisitChildren(throwExpression, data);
		}

		public virtual S? VisitTupleExpression(TupleExpression tupleExpression, T data)
		{
			return VisitChildren(tupleExpression, data);
		}

		public virtual S? VisitTypeOfExpression(TypeOfExpression typeOfExpression, T data)
		{
			return VisitChildren(typeOfExpression, data);
		}

		public virtual S? VisitTypeReferenceExpression(TypeReferenceExpression typeReferenceExpression, T data)
		{
			return VisitChildren(typeReferenceExpression, data);
		}

		public virtual S? VisitUnaryOperatorExpression(UnaryOperatorExpression unaryOperatorExpression, T data)
		{
			return VisitChildren(unaryOperatorExpression, data);
		}

		public virtual S? VisitUncheckedExpression(UncheckedExpression uncheckedExpression, T data)
		{
			return VisitChildren(uncheckedExpression, data);
		}

		public virtual S? VisitQueryExpression(QueryExpression queryExpression, T data)
		{
			return VisitChildren(queryExpression, data);
		}

		public virtual S? VisitQueryContinuationClause(QueryContinuationClause queryContinuationClause, T data)
		{
			return VisitChildren(queryContinuationClause, data);
		}

		public virtual S? VisitQueryFromClause(QueryFromClause queryFromClause, T data)
		{
			return VisitChildren(queryFromClause, data);
		}

		public virtual S? VisitQueryLetClause(QueryLetClause queryLetClause, T data)
		{
			return VisitChildren(queryLetClause, data);
		}

		public virtual S? VisitQueryWhereClause(QueryWhereClause queryWhereClause, T data)
		{
			return VisitChildren(queryWhereClause, data);
		}

		public virtual S? VisitQueryJoinClause(QueryJoinClause queryJoinClause, T data)
		{
			return VisitChildren(queryJoinClause, data);
		}

		public virtual S? VisitQueryOrderClause(QueryOrderClause queryOrderClause, T data)
		{
			return VisitChildren(queryOrderClause, data);
		}

		public virtual S? VisitQueryOrdering(QueryOrdering queryOrdering, T data)
		{
			return VisitChildren(queryOrdering, data);
		}

		public virtual S? VisitQuerySelectClause(QuerySelectClause querySelectClause, T data)
		{
			return VisitChildren(querySelectClause, data);
		}

		public virtual S? VisitQueryGroupClause(QueryGroupClause queryGroupClause, T data)
		{
			return VisitChildren(queryGroupClause, data);
		}

		public virtual S? VisitAsExpression(AsExpression asExpression, T data)
		{
			return VisitChildren(asExpression, data);
		}

		public virtual S? VisitIsExpression(IsExpression isExpression, T data)
		{
			return VisitChildren(isExpression, data);
		}

		public virtual S? VisitDefaultValueExpression(DefaultValueExpression defaultValueExpression, T data)
		{
			return VisitChildren(defaultValueExpression, data);
		}

		public virtual S? VisitUndocumentedExpression(UndocumentedExpression undocumentedExpression, T data)
		{
			return VisitChildren(undocumentedExpression, data);
		}

		public virtual S? VisitArrayInitializerExpression(ArrayInitializerExpression arrayInitializerExpression, T data)
		{
			return VisitChildren(arrayInitializerExpression, data);
		}

		public virtual S? VisitArraySpecifier(ArraySpecifier arraySpecifier, T data)
		{
			return VisitChildren(arraySpecifier, data);
		}

		public virtual S? VisitNamedArgumentExpression(NamedArgumentExpression namedArgumentExpression, T data)
		{
			return VisitChildren(namedArgumentExpression, data);
		}

		public virtual S? VisitNamedExpression(NamedExpression namedExpression, T data)
		{
			return VisitChildren(namedExpression, data);
		}

		public virtual S? VisitSingleVariableDesignation(SingleVariableDesignation singleVariableDesignation, T data)
		{
			return VisitChildren(singleVariableDesignation, data);
		}

		public virtual S? VisitParenthesizedVariableDesignation(ParenthesizedVariableDesignation parenthesizedVariableDesignation, T data)
		{
			return VisitChildren(parenthesizedVariableDesignation, data);
		}

		public virtual S? VisitErrorNode(AstNode errorNode, T data)
		{
			return VisitChildren(errorNode, data);
		}

		public virtual S? VisitPatternPlaceholder(AstNode placeholder, PatternMatching.Pattern pattern, T data)
		{
			return VisitChildren(placeholder, data);
		}

		public virtual S? VisitWithInitializerExpression(WithInitializerExpression withInitializerExpression, T data)
		{
			return VisitChildren(withInitializerExpression, data);
		}
	}
}