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# AST Node Types
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Comprehensive enumeration of all Abstract Syntax Tree node types for JavaScript and TypeScript, enabling type-safe node identification and processing throughout the typescript-eslint ecosystem.
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## Capabilities
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### AST_NODE_TYPES Enum
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The complete enumeration of all AST node types supported by TypeScript-ESTree.
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```typescript { .api }
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enum AST_NODE_TYPES {
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  // Core JavaScript nodes
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  AccessorProperty = 'AccessorProperty',
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  ArrayExpression = 'ArrayExpression',
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  ArrayPattern = 'ArrayPattern',
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  ArrowFunctionExpression = 'ArrowFunctionExpression',
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  AssignmentExpression = 'AssignmentExpression',
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  AssignmentPattern = 'AssignmentPattern',
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  AwaitExpression = 'AwaitExpression',
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  BinaryExpression = 'BinaryExpression',
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  BlockStatement = 'BlockStatement',
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  BreakStatement = 'BreakStatement',
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  CallExpression = 'CallExpression',
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  CatchClause = 'CatchClause',
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  ChainExpression = 'ChainExpression',
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  ClassBody = 'ClassBody',
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  ClassDeclaration = 'ClassDeclaration',
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  ClassExpression = 'ClassExpression',
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  ConditionalExpression = 'ConditionalExpression',
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  ContinueStatement = 'ContinueStatement',
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  DebuggerStatement = 'DebuggerStatement',
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  Decorator = 'Decorator',
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  DoWhileStatement = 'DoWhileStatement',
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  EmptyStatement = 'EmptyStatement',
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  ExportAllDeclaration = 'ExportAllDeclaration',
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  ExportDefaultDeclaration = 'ExportDefaultDeclaration',
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  ExportNamedDeclaration = 'ExportNamedDeclaration',
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  ExportSpecifier = 'ExportSpecifier',
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  ExpressionStatement = 'ExpressionStatement',
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  ForInStatement = 'ForInStatement',
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  ForOfStatement = 'ForOfStatement',
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  ForStatement = 'ForStatement',
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  FunctionDeclaration = 'FunctionDeclaration',
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  FunctionExpression = 'FunctionExpression',
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  Identifier = 'Identifier',
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  IfStatement = 'IfStatement',
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  ImportAttribute = 'ImportAttribute',
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  ImportDeclaration = 'ImportDeclaration',
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  ImportDefaultSpecifier = 'ImportDefaultSpecifier',
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  ImportExpression = 'ImportExpression',
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  ImportNamespaceSpecifier = 'ImportNamespaceSpecifier',
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  ImportSpecifier = 'ImportSpecifier',
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  LabeledStatement = 'LabeledStatement',
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  Literal = 'Literal',
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  LogicalExpression = 'LogicalExpression',
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  MemberExpression = 'MemberExpression',
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  MetaProperty = 'MetaProperty',
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  MethodDefinition = 'MethodDefinition',
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  NewExpression = 'NewExpression',
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  ObjectExpression = 'ObjectExpression',
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  ObjectPattern = 'ObjectPattern',
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  PrivateIdentifier = 'PrivateIdentifier',
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  Program = 'Program',
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  Property = 'Property',
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  PropertyDefinition = 'PropertyDefinition',
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  RestElement = 'RestElement',
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  ReturnStatement = 'ReturnStatement',
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  SequenceExpression = 'SequenceExpression',
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  SpreadElement = 'SpreadElement',
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  StaticBlock = 'StaticBlock',
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  Super = 'Super',
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  SwitchCase = 'SwitchCase',
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  SwitchStatement = 'SwitchStatement',
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  TaggedTemplateExpression = 'TaggedTemplateExpression',
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  TemplateElement = 'TemplateElement',
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  TemplateLiteral = 'TemplateLiteral',
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  ThisExpression = 'ThisExpression',
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  ThrowStatement = 'ThrowStatement',
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  TryStatement = 'TryStatement',
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  UnaryExpression = 'UnaryExpression',
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  UpdateExpression = 'UpdateExpression',
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  VariableDeclaration = 'VariableDeclaration',
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  VariableDeclarator = 'VariableDeclarator',
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  WhileStatement = 'WhileStatement',
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  WithStatement = 'WithStatement',
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  YieldExpression = 'YieldExpression',
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  // JSX nodes
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  JSXAttribute = 'JSXAttribute',
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  JSXClosingElement = 'JSXClosingElement',
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  JSXClosingFragment = 'JSXClosingFragment',
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  JSXElement = 'JSXElement',
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  JSXEmptyExpression = 'JSXEmptyExpression',
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  JSXExpressionContainer = 'JSXExpressionContainer',
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  JSXFragment = 'JSXFragment',
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  JSXIdentifier = 'JSXIdentifier',
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  JSXMemberExpression = 'JSXMemberExpression',
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  JSXNamespacedName = 'JSXNamespacedName',
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  JSXOpeningElement = 'JSXOpeningElement',
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  JSXOpeningFragment = 'JSXOpeningFragment',
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  JSXSpreadAttribute = 'JSXSpreadAttribute',
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  JSXSpreadChild = 'JSXSpreadChild',
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  JSXText = 'JSXText',
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  // TypeScript-specific nodes
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  TSAbstractAccessorProperty = 'TSAbstractAccessorProperty',
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  TSAbstractKeyword = 'TSAbstractKeyword',
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  TSAbstractMethodDefinition = 'TSAbstractMethodDefinition',
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  TSAbstractPropertyDefinition = 'TSAbstractPropertyDefinition',
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  TSAnyKeyword = 'TSAnyKeyword',
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  TSArrayType = 'TSArrayType',
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  TSAsExpression = 'TSAsExpression',
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  TSAsyncKeyword = 'TSAsyncKeyword',
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  TSBigIntKeyword = 'TSBigIntKeyword',
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  TSBooleanKeyword = 'TSBooleanKeyword',
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  TSCallSignatureDeclaration = 'TSCallSignatureDeclaration',
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  TSClassImplements = 'TSClassImplements',
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  TSConditionalType = 'TSConditionalType',
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  TSConstructorType = 'TSConstructorType',
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  TSConstructSignatureDeclaration = 'TSConstructSignatureDeclaration',
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  TSDeclareFunction = 'TSDeclareFunction',
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  TSDeclareKeyword = 'TSDeclareKeyword',
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  TSEmptyBodyFunctionExpression = 'TSEmptyBodyFunctionExpression',
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  TSEnumBody = 'TSEnumBody',
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  TSEnumDeclaration = 'TSEnumDeclaration',
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  TSEnumMember = 'TSEnumMember',
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  TSExportAssignment = 'TSExportAssignment',
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  TSExportKeyword = 'TSExportKeyword',
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  TSExternalModuleReference = 'TSExternalModuleReference',
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  TSFunctionType = 'TSFunctionType',
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  TSImportEqualsDeclaration = 'TSImportEqualsDeclaration',
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  TSImportType = 'TSImportType',
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  TSIndexedAccessType = 'TSIndexedAccessType',
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  TSIndexSignature = 'TSIndexSignature',
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  TSInferType = 'TSInferType',
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  TSInstantiationExpression = 'TSInstantiationExpression',
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  TSInterfaceBody = 'TSInterfaceBody',
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  TSInterfaceDeclaration = 'TSInterfaceDeclaration',
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  TSInterfaceHeritage = 'TSInterfaceHeritage',
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  TSIntersectionType = 'TSIntersectionType',
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  TSIntrinsicKeyword = 'TSIntrinsicKeyword',
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  TSLiteralType = 'TSLiteralType',
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  TSMappedType = 'TSMappedType',
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  TSMethodSignature = 'TSMethodSignature',
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  TSModuleBlock = 'TSModuleBlock',
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  TSModuleDeclaration = 'TSModuleDeclaration',
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  TSNamedTupleMember = 'TSNamedTupleMember',
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  TSNamespaceExportDeclaration = 'TSNamespaceExportDeclaration',
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  TSNeverKeyword = 'TSNeverKeyword',
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  TSNonNullExpression = 'TSNonNullExpression',
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  TSNullKeyword = 'TSNullKeyword',
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  TSNumberKeyword = 'TSNumberKeyword',
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  TSObjectKeyword = 'TSObjectKeyword',
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  TSOptionalType = 'TSOptionalType',
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  TSParameterProperty = 'TSParameterProperty',
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  TSPrivateKeyword = 'TSPrivateKeyword',
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  TSPropertySignature = 'TSPropertySignature',
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  TSProtectedKeyword = 'TSProtectedKeyword',
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  TSPublicKeyword = 'TSPublicKeyword',
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  TSQualifiedName = 'TSQualifiedName',
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  TSReadonlyKeyword = 'TSReadonlyKeyword',
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  TSRestType = 'TSRestType',
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  TSSatisfiesExpression = 'TSSatisfiesExpression',
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  TSStaticKeyword = 'TSStaticKeyword',
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  TSStringKeyword = 'TSStringKeyword',
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  TSSymbolKeyword = 'TSSymbolKeyword',
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  TSTemplateLiteralType = 'TSTemplateLiteralType',
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  TSThisType = 'TSThisType',
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  TSTupleType = 'TSTupleType',
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  TSTypeAliasDeclaration = 'TSTypeAliasDeclaration',
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  TSTypeAnnotation = 'TSTypeAnnotation',
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  TSTypeAssertion = 'TSTypeAssertion',
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  TSTypeLiteral = 'TSTypeLiteral',
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  TSTypeOperator = 'TSTypeOperator',
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  TSTypeParameter = 'TSTypeParameter',
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  TSTypeParameterDeclaration = 'TSTypeParameterDeclaration',
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  TSTypeParameterInstantiation = 'TSTypeParameterInstantiation',
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  TSTypePredicate = 'TSTypePredicate',
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  TSTypeQuery = 'TSTypeQuery',
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  TSTypeReference = 'TSTypeReference',
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  TSUndefinedKeyword = 'TSUndefinedKeyword',
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  TSUnionType = 'TSUnionType',
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  TSUnknownKeyword = 'TSUnknownKeyword',
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  TSVoidKeyword = 'TSVoidKeyword',
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}
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```
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**Usage Examples:**
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```typescript
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import { AST_NODE_TYPES, TSESTree } from "@typescript-eslint/types";
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// Type-safe node identification
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function processNode(node: TSESTree.Node): void {
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  switch (node.type) {
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    case AST_NODE_TYPES.FunctionDeclaration:
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      // TypeScript knows this is a FunctionDeclaration
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      console.log(`Function name: ${node.id?.name}`);
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      break;
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    case AST_NODE_TYPES.VariableDeclaration:
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      // TypeScript knows this is a VariableDeclaration
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      node.declarations.forEach(declarator => {
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        if (declarator.id.type === AST_NODE_TYPES.Identifier) {
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          console.log(`Variable: ${declarator.id.name}`);
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        }
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      });
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      break;
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    case AST_NODE_TYPES.TSInterfaceDeclaration:
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      // TypeScript-specific node handling
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      console.log(`Interface: ${node.id.name}`);
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      break;
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  }
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}
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// Check for TypeScript-specific nodes
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function isTypeScriptNode(nodeType: AST_NODE_TYPES): boolean {
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  return nodeType.startsWith('TS');
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}
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// Group nodes by category
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const STATEMENT_NODES = [
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  AST_NODE_TYPES.BlockStatement,
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  AST_NODE_TYPES.BreakStatement,
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  AST_NODE_TYPES.ContinueStatement,
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  AST_NODE_TYPES.DoWhileStatement,
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  AST_NODE_TYPES.ExpressionStatement,
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  AST_NODE_TYPES.ForStatement,
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  AST_NODE_TYPES.IfStatement,
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  AST_NODE_TYPES.ReturnStatement,
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  AST_NODE_TYPES.WhileStatement,
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] as const;
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```
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## Node Categories
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The AST node types can be organized into several logical categories:
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### Core Language Constructs
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- **Declarations**: `FunctionDeclaration`, `VariableDeclaration`, `ClassDeclaration`
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- **Statements**: `IfStatement`, `ForStatement`, `WhileStatement`, `BlockStatement`
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- **Expressions**: `BinaryExpression`, `CallExpression`, `MemberExpression`
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- **Literals**: `Literal`, `TemplateLiteral`
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- **Identifiers**: `Identifier`, `PrivateIdentifier`
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### Modern JavaScript Features
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- **Classes**: `ClassBody`, `MethodDefinition`, `PropertyDefinition`, `StaticBlock`
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- **Modules**: `ImportDeclaration`, `ExportDeclaration`, `ImportSpecifier`
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- **Async/Await**: `AwaitExpression`, `ArrowFunctionExpression`
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- **Destructuring**: `ArrayPattern`, `ObjectPattern`, `RestElement`
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### JSX Support
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- **Elements**: `JSXElement`, `JSXFragment`, `JSXText`
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- **Attributes**: `JSXAttribute`, `JSXSpreadAttribute`
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- **Identifiers**: `JSXIdentifier`, `JSXMemberExpression`
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### TypeScript Extensions
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- **Type Annotations**: `TSTypeAnnotation`, `TSAsExpression`, `TSTypeAssertion`
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- **Declarations**: `TSInterfaceDeclaration`, `TSTypeAliasDeclaration`, `TSEnumDeclaration`
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- **Type System**: `TSUnionType`, `TSIntersectionType`, `TSMappedType`
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- **Keywords**: `TSPublicKeyword`, `TSPrivateKeyword`, `TSReadonlyKeyword`