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@babel/types

This module contains methods for building ASTs manually and for checking the types of AST nodes.

Install​

npm install --save-dev @babel/types

API​

Node Builders​

anyTypeAnnotation​

JavaScript
t.anyTypeAnnotation();

See also t.isAnyTypeAnnotation(node, opts) and t.assertAnyTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

argumentPlaceholder​

JavaScript
t.argumentPlaceholder();

See also t.isArgumentPlaceholder(node, opts) and t.assertArgumentPlaceholder(node, opts).

arrayExpression​

JavaScript
t.arrayExpression(elements);

See also t.isArrayExpression(node, opts) and t.assertArrayExpression(node, opts).

AST Node ArrayExpression shape:

  • elements: Array<null | Expression | SpreadElement> (default: [])

Aliases: Standardized, Expression

arrayPattern​

JavaScript
t.arrayPattern(elements);

See also t.isArrayPattern(node, opts) and t.assertArrayPattern(node, opts).

AST Node ArrayPattern shape:

  • elements: Array<null | PatternLike | LVal> (required)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • typeAnnotation: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)

Aliases: Standardized, Pattern, PatternLike, LVal

arrayTypeAnnotation​

JavaScript
t.arrayTypeAnnotation(elementType);

See also t.isArrayTypeAnnotation(node, opts) and t.assertArrayTypeAnnotation(node, opts).

AST Node ArrayTypeAnnotation shape:

  • elementType: FlowType (required)

Aliases: Flow, FlowType

arrowFunctionExpression​

JavaScript
t.arrowFunctionExpression(params, body, async);

See also t.isArrowFunctionExpression(node, opts) and t.assertArrowFunctionExpression(node, opts).

AST Node ArrowFunctionExpression shape:

  • params: Array<Identifier | Pattern | RestElement> (required)
  • body: BlockStatement | Expression (required)
  • async: boolean (default: false)
  • expression: boolean (required)
  • generator: boolean (default: false, excluded from builder function)
  • predicate: DeclaredPredicate | InferredPredicate (default: null, excluded from builder function)
  • returnType: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)
  • typeParameters: TypeParameterDeclaration | TSTypeParameterDeclaration | Noop (default: null, excluded from builder function)

Aliases: Standardized, Scopable, Function, BlockParent, FunctionParent, Expression, Pureish

assignmentExpression​

JavaScript
t.assignmentExpression(operator, left, right);

See also t.isAssignmentExpression(node, opts) and t.assertAssignmentExpression(node, opts).

AST Node AssignmentExpression shape:

  • operator: string (required)
  • left: LVal | OptionalMemberExpression (required)
  • right: Expression (required)

Aliases: Standardized, Expression

assignmentPattern​

JavaScript
t.assignmentPattern(left, right);

See also t.isAssignmentPattern(node, opts) and t.assertAssignmentPattern(node, opts).

AST Node AssignmentPattern shape:

  • left: Identifier | ObjectPattern | ArrayPattern | MemberExpression | TSAsExpression | TSSatisfiesExpression | TSTypeAssertion | TSNonNullExpression (required)
  • right: Expression (required)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • typeAnnotation: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)

Aliases: Standardized, Pattern, PatternLike, LVal

awaitExpression​

JavaScript
t.awaitExpression(argument);

See also t.isAwaitExpression(node, opts) and t.assertAwaitExpression(node, opts).

AST Node AwaitExpression shape:

  • argument: Expression (required)

Aliases: Standardized, Expression, Terminatorless

bigIntLiteral​

JavaScript
t.bigIntLiteral(value);

See also t.isBigIntLiteral(node, opts) and t.assertBigIntLiteral(node, opts).

AST Node BigIntLiteral shape:

  • value: string (required)

Aliases: Standardized, Expression, Pureish, Literal, Immutable

binaryExpression​

JavaScript
t.binaryExpression(operator, left, right);

See also t.isBinaryExpression(node, opts) and t.assertBinaryExpression(node, opts).

AST Node BinaryExpression shape:

  • operator: "+" | "-" | "/" | "%" | "*" | "**" | "&" | "|" | ">>" | ">>>" | "<<" | "^" | "==" | "===" | "!=" | "!==" | "in" | "instanceof" | ">" | "<" | ">=" | "<=" | "|>" (required)
  • left: Expression | PrivateName (required)
  • right: Expression (required)

Aliases: Standardized, Binary, Expression

bindExpression​

JavaScript
t.bindExpression(object, callee);

See also t.isBindExpression(node, opts) and t.assertBindExpression(node, opts).

AST Node BindExpression shape:

  • object: Expression (required)
  • callee: Expression (required)

Aliases: Expression

blockStatement​

JavaScript
t.blockStatement(body, directives);

See also t.isBlockStatement(node, opts) and t.assertBlockStatement(node, opts).

AST Node BlockStatement shape:

  • body: Array<Statement> (required)
  • directives: Array<Directive> (default: [])

Aliases: Standardized, Scopable, BlockParent, Block, Statement

booleanLiteral​

JavaScript
t.booleanLiteral(value);

See also t.isBooleanLiteral(node, opts) and t.assertBooleanLiteral(node, opts).

AST Node BooleanLiteral shape:

  • value: boolean (required)

Aliases: Standardized, Expression, Pureish, Literal, Immutable

booleanLiteralTypeAnnotation​

JavaScript
t.booleanLiteralTypeAnnotation(value);

See also t.isBooleanLiteralTypeAnnotation(node, opts) and t.assertBooleanLiteralTypeAnnotation(node, opts).

AST Node BooleanLiteralTypeAnnotation shape:

  • value: boolean (required)

Aliases: Flow, FlowType

booleanTypeAnnotation​

JavaScript
t.booleanTypeAnnotation();

See also t.isBooleanTypeAnnotation(node, opts) and t.assertBooleanTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

breakStatement​

JavaScript
t.breakStatement(label);

See also t.isBreakStatement(node, opts) and t.assertBreakStatement(node, opts).

AST Node BreakStatement shape:

  • label: Identifier (default: null)

Aliases: Standardized, Statement, Terminatorless, CompletionStatement

callExpression​

JavaScript
t.callExpression(callee, arguments);

See also t.isCallExpression(node, opts) and t.assertCallExpression(node, opts).

AST Node CallExpression shape:

  • callee: Expression | Super | V8IntrinsicIdentifier (required)
  • arguments: Array<Expression | SpreadElement | ArgumentPlaceholder> (required)
  • optional: boolean (default: null, excluded from builder function)
  • typeArguments: TypeParameterInstantiation (default: null, excluded from builder function)
  • typeParameters: TSTypeParameterInstantiation (default: null, excluded from builder function)

Aliases: Standardized, Expression

catchClause​

JavaScript
t.catchClause(param, body);

See also t.isCatchClause(node, opts) and t.assertCatchClause(node, opts).

AST Node CatchClause shape:

  • param: Identifier | ArrayPattern | ObjectPattern (default: null)
  • body: BlockStatement (required)

Aliases: Standardized, Scopable, BlockParent

classAccessorProperty​

JavaScript
t.classAccessorProperty(key, value, typeAnnotation, decorators, computed, static);

See also t.isClassAccessorProperty(node, opts) and t.assertClassAccessorProperty(node, opts).

AST Node ClassAccessorProperty shape:

  • key: Identifier | StringLiteral | NumericLiteral | BigIntLiteral | Expression | PrivateName (required)
  • value: Expression (default: null)
  • typeAnnotation: TypeAnnotation | TSTypeAnnotation | Noop (default: null)
  • decorators: Array<Decorator> (default: null)
  • computed: boolean (default: false)
  • static: boolean (default: false)
  • abstract: boolean (default: null, excluded from builder function)
  • accessibility: "public" | "private" | "protected" (default: null, excluded from builder function)
  • declare: boolean (default: null, excluded from builder function)
  • definite: boolean (default: null, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • override: boolean (default: false, excluded from builder function)
  • readonly: boolean (default: null, excluded from builder function)
  • variance: Variance (default: null, excluded from builder function)

Aliases: Standardized, Property, Accessor

classBody​

JavaScript
t.classBody(body);

See also t.isClassBody(node, opts) and t.assertClassBody(node, opts).

AST Node ClassBody shape:

  • body: Array<ClassMethod | ClassPrivateMethod | ClassProperty | ClassPrivateProperty | ClassAccessorProperty | TSDeclareMethod | TSIndexSignature | StaticBlock> (required)

Aliases: Standardized

classDeclaration​

JavaScript
t.classDeclaration(id, superClass, body, decorators);

See also t.isClassDeclaration(node, opts) and t.assertClassDeclaration(node, opts).

AST Node ClassDeclaration shape:

  • id: Identifier (default: null)
  • superClass: Expression (default: null)
  • body: ClassBody (required)
  • decorators: Array<Decorator> (default: null)
  • abstract: boolean (default: null, excluded from builder function)
  • declare: boolean (default: null, excluded from builder function)
  • implements: Array<TSExpressionWithTypeArguments | ClassImplements> (default: null, excluded from builder function)
  • mixins: InterfaceExtends (default: null, excluded from builder function)
  • superTypeParameters: TypeParameterInstantiation | TSTypeParameterInstantiation (default: null, excluded from builder function)
  • typeParameters: TypeParameterDeclaration | TSTypeParameterDeclaration | Noop (default: null, excluded from builder function)

Aliases: Standardized, Scopable, Class, Statement, Declaration

classExpression​

JavaScript
t.classExpression(id, superClass, body, decorators);

See also t.isClassExpression(node, opts) and t.assertClassExpression(node, opts).

AST Node ClassExpression shape:

  • id: Identifier (default: null)
  • superClass: Expression (default: null)
  • body: ClassBody (required)
  • decorators: Array<Decorator> (default: null)
  • implements: Array<TSExpressionWithTypeArguments | ClassImplements> (default: null, excluded from builder function)
  • mixins: InterfaceExtends (default: null, excluded from builder function)
  • superTypeParameters: TypeParameterInstantiation | TSTypeParameterInstantiation (default: null, excluded from builder function)
  • typeParameters: TypeParameterDeclaration | TSTypeParameterDeclaration | Noop (default: null, excluded from builder function)

Aliases: Standardized, Scopable, Class, Expression

classImplements​

JavaScript
t.classImplements(id, typeParameters);

See also t.isClassImplements(node, opts) and t.assertClassImplements(node, opts).

AST Node ClassImplements shape:

  • id: Identifier (required)
  • typeParameters: TypeParameterInstantiation (default: null)

Aliases: Flow

classMethod​

JavaScript
t.classMethod(kind, key, params, body, computed, static, generator, async);

See also t.isClassMethod(node, opts) and t.assertClassMethod(node, opts).

AST Node ClassMethod shape:

  • kind: "get" | "set" | "method" | "constructor" (default: 'method')
  • key: if computed then Expression else Identifier | Literal (required)
  • params: Array<Identifier | Pattern | RestElement | TSParameterProperty> (required)
  • body: BlockStatement (required)
  • computed: boolean (default: false)
  • static: boolean (default: false)
  • generator: boolean (default: false)
  • async: boolean (default: false)
  • abstract: boolean (default: null, excluded from builder function)
  • access: "public" | "private" | "protected" (default: null, excluded from builder function)
  • accessibility: "public" | "private" | "protected" (default: null, excluded from builder function)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • override: boolean (default: false, excluded from builder function)
  • returnType: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)
  • typeParameters: TypeParameterDeclaration | TSTypeParameterDeclaration | Noop (default: null, excluded from builder function)

Aliases: Standardized, Function, Scopable, BlockParent, FunctionParent, Method

classPrivateMethod​

JavaScript
t.classPrivateMethod(kind, key, params, body, static);

See also t.isClassPrivateMethod(node, opts) and t.assertClassPrivateMethod(node, opts).

AST Node ClassPrivateMethod shape:

  • kind: "get" | "set" | "method" (default: 'method')
  • key: PrivateName (required)
  • params: Array<Identifier | Pattern | RestElement | TSParameterProperty> (required)
  • body: BlockStatement (required)
  • static: boolean (default: false)
  • abstract: boolean (default: null, excluded from builder function)
  • access: "public" | "private" | "protected" (default: null, excluded from builder function)
  • accessibility: "public" | "private" | "protected" (default: null, excluded from builder function)
  • async: boolean (default: false, excluded from builder function)
  • computed: 'false' (default: false, excluded from builder function)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • generator: boolean (default: false, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • override: boolean (default: false, excluded from builder function)
  • returnType: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)
  • typeParameters: TypeParameterDeclaration | TSTypeParameterDeclaration | Noop (default: null, excluded from builder function)

Aliases: Standardized, Function, Scopable, BlockParent, FunctionParent, Method, Private

classPrivateProperty​

JavaScript
t.classPrivateProperty(key, value, decorators, static);

See also t.isClassPrivateProperty(node, opts) and t.assertClassPrivateProperty(node, opts).

AST Node ClassPrivateProperty shape:

  • key: PrivateName (required)
  • value: Expression (default: null)
  • decorators: Array<Decorator> (default: null)
  • static: boolean (default: false)
  • definite: boolean (default: null, excluded from builder function)
  • readonly: boolean (default: null, excluded from builder function)
  • typeAnnotation: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)
  • variance: Variance (default: null, excluded from builder function)

Aliases: Standardized, Property, Private

classProperty​

JavaScript
t.classProperty(key, value, typeAnnotation, decorators, computed, static);
History
VersionChanges
v7.6.0Supports static

See also t.isClassProperty(node, opts) and t.assertClassProperty(node, opts).

AST Node ClassProperty shape:

  • key: Identifier | StringLiteral | NumericLiteral | BigIntLiteral | Expression (required)
  • value: Expression (default: null)
  • typeAnnotation: TypeAnnotation | TSTypeAnnotation | Noop (default: null)
  • decorators: Array<Decorator> (default: null)
  • computed: boolean (default: false)
  • static: boolean (default: false)
  • abstract: boolean (default: null, excluded from builder function)
  • accessibility: "public" | "private" | "protected" (default: null, excluded from builder function)
  • declare: boolean (default: null, excluded from builder function)
  • definite: boolean (default: null, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • override: boolean (default: false, excluded from builder function)
  • readonly: boolean (default: null, excluded from builder function)
  • variance: Variance (default: null, excluded from builder function)

Aliases: Standardized, Property

conditionalExpression​

JavaScript
t.conditionalExpression(test, consequent, alternate);

See also t.isConditionalExpression(node, opts) and t.assertConditionalExpression(node, opts).

AST Node ConditionalExpression shape:

  • test: Expression (required)
  • consequent: Expression (required)
  • alternate: Expression (required)

Aliases: Standardized, Expression, Conditional

continueStatement​

JavaScript
t.continueStatement(label);

See also t.isContinueStatement(node, opts) and t.assertContinueStatement(node, opts).

AST Node ContinueStatement shape:

  • label: Identifier (default: null)

Aliases: Standardized, Statement, Terminatorless, CompletionStatement

debuggerStatement​

JavaScript
t.debuggerStatement();

See also t.isDebuggerStatement(node, opts) and t.assertDebuggerStatement(node, opts).

Aliases: Standardized, Statement

decimalLiteral​

JavaScript
t.decimalLiteral(value);

See also t.isDecimalLiteral(node, opts) and t.assertDecimalLiteral(node, opts).

AST Node DecimalLiteral shape:

  • value: string (required)

Aliases: Expression, Pureish, Literal, Immutable

declareClass​

JavaScript
t.declareClass(id, typeParameters, extends, body);

See also t.isDeclareClass(node, opts) and t.assertDeclareClass(node, opts).

AST Node DeclareClass shape:

  • id: Identifier (required)
  • typeParameters: TypeParameterDeclaration (default: null)
  • extends: Array<InterfaceExtends> (default: null)
  • body: ObjectTypeAnnotation (required)
  • implements: Array<ClassImplements> (default: null, excluded from builder function)
  • mixins: Array<InterfaceExtends> (default: null, excluded from builder function)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declareExportAllDeclaration​

JavaScript
t.declareExportAllDeclaration(source, attributes);

See also t.isDeclareExportAllDeclaration(node, opts) and t.assertDeclareExportAllDeclaration(node, opts).

AST Node DeclareExportAllDeclaration shape:

  • source: StringLiteral (required)
  • attributes: Array<ImportAttribute> (default: null)
  • assertions: Array<ImportAttribute> (default: null, excluded from builder function)
  • exportKind: "type" | "value" (default: null, excluded from builder function)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declareExportDeclaration​

JavaScript
t.declareExportDeclaration(declaration, specifiers, source, attributes);

See also t.isDeclareExportDeclaration(node, opts) and t.assertDeclareExportDeclaration(node, opts).

AST Node DeclareExportDeclaration shape:

  • declaration: Flow (default: null)
  • specifiers: Array<ExportSpecifier | ExportNamespaceSpecifier> (default: null)
  • source: StringLiteral (default: null)
  • attributes: Array<ImportAttribute> (default: null)
  • assertions: Array<ImportAttribute> (default: null, excluded from builder function)
  • default: boolean (default: null, excluded from builder function)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declareFunction​

JavaScript
t.declareFunction(id);

See also t.isDeclareFunction(node, opts) and t.assertDeclareFunction(node, opts).

AST Node DeclareFunction shape:

  • id: Identifier (required)
  • predicate: DeclaredPredicate (default: null, excluded from builder function)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declareInterface​

JavaScript
t.declareInterface(id, typeParameters, extends, body);

See also t.isDeclareInterface(node, opts) and t.assertDeclareInterface(node, opts).

AST Node DeclareInterface shape:

  • id: Identifier (required)
  • typeParameters: TypeParameterDeclaration (default: null)
  • extends: Array<InterfaceExtends> (default: null)
  • body: ObjectTypeAnnotation (required)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declareModule​

JavaScript
t.declareModule(id, body, kind);

See also t.isDeclareModule(node, opts) and t.assertDeclareModule(node, opts).

AST Node DeclareModule shape:

  • id: Identifier | StringLiteral (required)
  • body: BlockStatement (required)
  • kind: "CommonJS" | "ES" (default: null)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declareModuleExports​

JavaScript
t.declareModuleExports(typeAnnotation);

See also t.isDeclareModuleExports(node, opts) and t.assertDeclareModuleExports(node, opts).

AST Node DeclareModuleExports shape:

  • typeAnnotation: TypeAnnotation (required)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declareOpaqueType​

JavaScript
t.declareOpaqueType(id, typeParameters, supertype);

See also t.isDeclareOpaqueType(node, opts) and t.assertDeclareOpaqueType(node, opts).

AST Node DeclareOpaqueType shape:

  • id: Identifier (required)
  • typeParameters: TypeParameterDeclaration (default: null)
  • supertype: FlowType (default: null)
  • impltype: FlowType (default: null, excluded from builder function)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declareTypeAlias​

JavaScript
t.declareTypeAlias(id, typeParameters, right);

See also t.isDeclareTypeAlias(node, opts) and t.assertDeclareTypeAlias(node, opts).

AST Node DeclareTypeAlias shape:

  • id: Identifier (required)
  • typeParameters: TypeParameterDeclaration (default: null)
  • right: FlowType (required)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declareVariable​

JavaScript
t.declareVariable(id);

See also t.isDeclareVariable(node, opts) and t.assertDeclareVariable(node, opts).

AST Node DeclareVariable shape:

  • id: Identifier (required)

Aliases: Flow, FlowDeclaration, Statement, Declaration

declaredPredicate​

JavaScript
t.declaredPredicate(value);

See also t.isDeclaredPredicate(node, opts) and t.assertDeclaredPredicate(node, opts).

AST Node DeclaredPredicate shape:

  • value: Flow (required)

Aliases: Flow, FlowPredicate

decorator​

JavaScript
t.decorator(expression);

See also t.isDecorator(node, opts) and t.assertDecorator(node, opts).

AST Node Decorator shape:

  • expression: Expression (required)

directive​

JavaScript
t.directive(value);

See also t.isDirective(node, opts) and t.assertDirective(node, opts).

AST Node Directive shape:

  • value: DirectiveLiteral (required)

Aliases: Standardized

directiveLiteral​

JavaScript
t.directiveLiteral(value);

See also t.isDirectiveLiteral(node, opts) and t.assertDirectiveLiteral(node, opts).

AST Node DirectiveLiteral shape:

  • value: string (required)

Aliases: Standardized

doExpression​

JavaScript
t.doExpression(body, async);

See also t.isDoExpression(node, opts) and t.assertDoExpression(node, opts).

AST Node DoExpression shape:

  • body: BlockStatement (required)
  • async: boolean (default: false)

Aliases: Expression

doWhileStatement​

JavaScript
t.doWhileStatement(test, body);

See also t.isDoWhileStatement(node, opts) and t.assertDoWhileStatement(node, opts).

AST Node DoWhileStatement shape:

  • test: Expression (required)
  • body: Statement (required)

Aliases: Standardized, Statement, BlockParent, Loop, While, Scopable

emptyStatement​

JavaScript
t.emptyStatement();

See also t.isEmptyStatement(node, opts) and t.assertEmptyStatement(node, opts).

Aliases: Standardized, Statement

emptyTypeAnnotation​

JavaScript
t.emptyTypeAnnotation();

See also t.isEmptyTypeAnnotation(node, opts) and t.assertEmptyTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

enumBooleanBody​

JavaScript
t.enumBooleanBody(members);

See also t.isEnumBooleanBody(node, opts) and t.assertEnumBooleanBody(node, opts).

AST Node EnumBooleanBody shape:

  • members: Array<EnumBooleanMember> (required)
  • explicitType: boolean (required)
  • hasUnknownMembers: boolean (required)

Aliases: Flow, EnumBody

enumBooleanMember​

JavaScript
t.enumBooleanMember(id);

See also t.isEnumBooleanMember(node, opts) and t.assertEnumBooleanMember(node, opts).

AST Node EnumBooleanMember shape:

  • id: Identifier (required)
  • init: BooleanLiteral (required)

Aliases: Flow, EnumMember

enumDeclaration​

JavaScript
t.enumDeclaration(id, body);

See also t.isEnumDeclaration(node, opts) and t.assertEnumDeclaration(node, opts).

AST Node EnumDeclaration shape:

  • id: Identifier (required)
  • body: EnumBooleanBody | EnumNumberBody | EnumStringBody | EnumSymbolBody (required)

Aliases: Flow, Statement, Declaration

enumDefaultedMember​

JavaScript
t.enumDefaultedMember(id);

See also t.isEnumDefaultedMember(node, opts) and t.assertEnumDefaultedMember(node, opts).

AST Node EnumDefaultedMember shape:

  • id: Identifier (required)

Aliases: Flow, EnumMember

enumNumberBody​

JavaScript
t.enumNumberBody(members);

See also t.isEnumNumberBody(node, opts) and t.assertEnumNumberBody(node, opts).

AST Node EnumNumberBody shape:

  • members: Array<EnumNumberMember> (required)
  • explicitType: boolean (required)
  • hasUnknownMembers: boolean (required)

Aliases: Flow, EnumBody

enumNumberMember​

JavaScript
t.enumNumberMember(id, init);

See also t.isEnumNumberMember(node, opts) and t.assertEnumNumberMember(node, opts).

AST Node EnumNumberMember shape:

  • id: Identifier (required)
  • init: NumericLiteral (required)

Aliases: Flow, EnumMember

enumStringBody​

JavaScript
t.enumStringBody(members);

See also t.isEnumStringBody(node, opts) and t.assertEnumStringBody(node, opts).

AST Node EnumStringBody shape:

  • members: Array<EnumStringMember | EnumDefaultedMember> (required)
  • explicitType: boolean (required)
  • hasUnknownMembers: boolean (required)

Aliases: Flow, EnumBody

enumStringMember​

JavaScript
t.enumStringMember(id, init);

See also t.isEnumStringMember(node, opts) and t.assertEnumStringMember(node, opts).

AST Node EnumStringMember shape:

  • id: Identifier (required)
  • init: StringLiteral (required)

Aliases: Flow, EnumMember

enumSymbolBody​

JavaScript
t.enumSymbolBody(members);

See also t.isEnumSymbolBody(node, opts) and t.assertEnumSymbolBody(node, opts).

AST Node EnumSymbolBody shape:

  • members: Array<EnumDefaultedMember> (required)
  • hasUnknownMembers: boolean (required)

Aliases: Flow, EnumBody

existsTypeAnnotation​

JavaScript
t.existsTypeAnnotation();

See also t.isExistsTypeAnnotation(node, opts) and t.assertExistsTypeAnnotation(node, opts).

Aliases: Flow, FlowType

exportAllDeclaration​

JavaScript
t.exportAllDeclaration(source);

See also t.isExportAllDeclaration(node, opts) and t.assertExportAllDeclaration(node, opts).

AST Node ExportAllDeclaration shape:

  • source: StringLiteral (required)
  • assertions: Array<ImportAttribute> (default: null, excluded from builder function)
  • attributes: Array<ImportAttribute> (default: null, excluded from builder function)
  • exportKind: "type" | "value" (default: null, excluded from builder function)

Aliases: Standardized, Statement, Declaration, ImportOrExportDeclaration, ExportDeclaration

exportDefaultDeclaration​

JavaScript
t.exportDefaultDeclaration(declaration);

See also t.isExportDefaultDeclaration(node, opts) and t.assertExportDefaultDeclaration(node, opts).

AST Node ExportDefaultDeclaration shape:

  • declaration: TSDeclareFunction | FunctionDeclaration | ClassDeclaration | Expression (required)
  • exportKind: "value" (default: null, excluded from builder function)

Aliases: Standardized, Statement, Declaration, ImportOrExportDeclaration, ExportDeclaration

exportDefaultSpecifier​

JavaScript
t.exportDefaultSpecifier(exported);

See also t.isExportDefaultSpecifier(node, opts) and t.assertExportDefaultSpecifier(node, opts).

AST Node ExportDefaultSpecifier shape:

  • exported: Identifier (required)

Aliases: ModuleSpecifier

exportNamedDeclaration​

JavaScript
t.exportNamedDeclaration(declaration, specifiers, source);

See also t.isExportNamedDeclaration(node, opts) and t.assertExportNamedDeclaration(node, opts).

AST Node ExportNamedDeclaration shape:

  • declaration: Declaration (default: null)
  • specifiers: Array<ExportSpecifier | ExportDefaultSpecifier | ExportNamespaceSpecifier> (default: [])
  • source: StringLiteral (default: null)
  • assertions: Array<ImportAttribute> (default: null, excluded from builder function)
  • attributes: Array<ImportAttribute> (default: null, excluded from builder function)
  • exportKind: "type" | "value" (default: null, excluded from builder function)

Aliases: Standardized, Statement, Declaration, ImportOrExportDeclaration, ExportDeclaration

exportNamespaceSpecifier​

JavaScript
t.exportNamespaceSpecifier(exported);

See also t.isExportNamespaceSpecifier(node, opts) and t.assertExportNamespaceSpecifier(node, opts).

AST Node ExportNamespaceSpecifier shape:

  • exported: Identifier (required)

Aliases: Standardized, ModuleSpecifier

exportSpecifier​

JavaScript
t.exportSpecifier(local, exported);

See also t.isExportSpecifier(node, opts) and t.assertExportSpecifier(node, opts).

AST Node ExportSpecifier shape:

  • local: Identifier (required)
  • exported: Identifier | StringLiteral (required)
  • exportKind: "type" | "value" (default: null, excluded from builder function)

Aliases: Standardized, ModuleSpecifier

expressionStatement​

JavaScript
t.expressionStatement(expression);

See also t.isExpressionStatement(node, opts) and t.assertExpressionStatement(node, opts).

AST Node ExpressionStatement shape:

  • expression: Expression (required)

Aliases: Standardized, Statement, ExpressionWrapper

file​

JavaScript
t.file(program, comments, tokens);

See also t.isFile(node, opts) and t.assertFile(node, opts).

AST Node File shape:

  • program: Program (required)
  • comments: Array<CommentBlock | CommentLine> (default: null)
  • tokens: Array<any> (default: null)

Aliases: Standardized

forInStatement​

JavaScript
t.forInStatement(left, right, body);

See also t.isForInStatement(node, opts) and t.assertForInStatement(node, opts).

AST Node ForInStatement shape:

  • left: VariableDeclaration | LVal (required)
  • right: Expression (required)
  • body: Statement (required)

Aliases: Standardized, Scopable, Statement, For, BlockParent, Loop, ForXStatement

forOfStatement​

JavaScript
t.forOfStatement(left, right, body, await);

See also t.isForOfStatement(node, opts) and t.assertForOfStatement(node, opts).

AST Node ForOfStatement shape:

  • left: VariableDeclaration | LVal (required)
  • right: Expression (required)
  • body: Statement (required)
  • await: boolean (default: false)

Aliases: Standardized, Scopable, Statement, For, BlockParent, Loop, ForXStatement

forStatement​

JavaScript
t.forStatement(init, test, update, body);

See also t.isForStatement(node, opts) and t.assertForStatement(node, opts).

AST Node ForStatement shape:

  • init: VariableDeclaration | Expression (default: null)
  • test: Expression (default: null)
  • update: Expression (default: null)
  • body: Statement (required)

Aliases: Standardized, Scopable, Statement, For, BlockParent, Loop

functionDeclaration​

JavaScript
t.functionDeclaration(id, params, body, generator, async);

See also t.isFunctionDeclaration(node, opts) and t.assertFunctionDeclaration(node, opts).

AST Node FunctionDeclaration shape:

  • id: Identifier (default: null)
  • params: Array<Identifier | Pattern | RestElement> (required)
  • body: BlockStatement (required)
  • generator: boolean (default: false)
  • async: boolean (default: false)
  • declare: boolean (default: null, excluded from builder function)
  • predicate: DeclaredPredicate | InferredPredicate (default: null, excluded from builder function)
  • returnType: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)
  • typeParameters: TypeParameterDeclaration | TSTypeParameterDeclaration | Noop (default: null, excluded from builder function)

Aliases: Standardized, Scopable, Function, BlockParent, FunctionParent, Statement, Pureish, Declaration

functionExpression​

JavaScript
t.functionExpression(id, params, body, generator, async);

See also t.isFunctionExpression(node, opts) and t.assertFunctionExpression(node, opts).

AST Node FunctionExpression shape:

  • id: Identifier (default: null)
  • params: Array<Identifier | Pattern | RestElement> (required)
  • body: BlockStatement (required)
  • generator: boolean (default: false)
  • async: boolean (default: false)
  • predicate: DeclaredPredicate | InferredPredicate (default: null, excluded from builder function)
  • returnType: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)
  • typeParameters: TypeParameterDeclaration | TSTypeParameterDeclaration | Noop (default: null, excluded from builder function)

Aliases: Standardized, Scopable, Function, BlockParent, FunctionParent, Expression, Pureish

functionTypeAnnotation​

JavaScript
t.functionTypeAnnotation(typeParameters, params, rest, returnType);

See also t.isFunctionTypeAnnotation(node, opts) and t.assertFunctionTypeAnnotation(node, opts).

AST Node FunctionTypeAnnotation shape:

  • typeParameters: TypeParameterDeclaration (default: null)
  • params: Array<FunctionTypeParam> (required)
  • rest: FunctionTypeParam (default: null)
  • returnType: FlowType (required)
  • this: FunctionTypeParam (default: null, excluded from builder function)

Aliases: Flow, FlowType

functionTypeParam​

JavaScript
t.functionTypeParam(name, typeAnnotation);

See also t.isFunctionTypeParam(node, opts) and t.assertFunctionTypeParam(node, opts).

AST Node FunctionTypeParam shape:

  • name: Identifier (default: null)
  • typeAnnotation: FlowType (required)
  • optional: boolean (default: null, excluded from builder function)

Aliases: Flow

genericTypeAnnotation​

JavaScript
t.genericTypeAnnotation(id, typeParameters);

See also t.isGenericTypeAnnotation(node, opts) and t.assertGenericTypeAnnotation(node, opts).

AST Node GenericTypeAnnotation shape:

  • id: Identifier | QualifiedTypeIdentifier (required)
  • typeParameters: TypeParameterInstantiation (default: null)

Aliases: Flow, FlowType

identifier​

JavaScript
t.identifier(name);

See also t.isIdentifier(node, opts) and t.assertIdentifier(node, opts).

AST Node Identifier shape:

  • name: string (required)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • typeAnnotation: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)

Aliases: Standardized, Expression, PatternLike, LVal, TSEntityName

ifStatement​

JavaScript
t.ifStatement(test, consequent, alternate);

See also t.isIfStatement(node, opts) and t.assertIfStatement(node, opts).

AST Node IfStatement shape:

  • test: Expression (required)
  • consequent: Statement (required)
  • alternate: Statement (default: null)

Aliases: Standardized, Statement, Conditional

import​

JavaScript
t.import();

See also t.isImport(node, opts) and t.assertImport(node, opts).

Aliases: Standardized, Expression

importAttribute​

JavaScript
t.importAttribute(key, value);

See also t.isImportAttribute(node, opts) and t.assertImportAttribute(node, opts).

AST Node ImportAttribute shape:

  • key: Identifier | StringLiteral (required)
  • value: StringLiteral (required)

importDeclaration​

JavaScript
t.importDeclaration(specifiers, source);
History
VersionChanges
v7.20.0Supports module

See also t.isImportDeclaration(node, opts) and t.assertImportDeclaration(node, opts).

AST Node ImportDeclaration shape:

  • specifiers: Array<ImportSpecifier | ImportDefaultSpecifier | ImportNamespaceSpecifier> (required)
  • source: StringLiteral (required)
  • assertions: Array<ImportAttribute> (default: null, excluded from builder function)
  • attributes: Array<ImportAttribute> (default: null, excluded from builder function)
  • importKind: "type" | "typeof" | "value" (default: null, excluded from builder function)
  • module: boolean (default: null, excluded from builder function)
  • phase: "source" | "defer" (default: null, excluded from builder function)

Aliases: Standardized, Statement, Declaration, ImportOrExportDeclaration

importDefaultSpecifier​

JavaScript
t.importDefaultSpecifier(local);

See also t.isImportDefaultSpecifier(node, opts) and t.assertImportDefaultSpecifier(node, opts).

AST Node ImportDefaultSpecifier shape:

  • local: Identifier (required)

Aliases: Standardized, ModuleSpecifier

importExpression​

JavaScript
t.importExpression(source, options);

See also t.isImportExpression(node, opts) and t.assertImportExpression(node, opts).

AST Node ImportExpression shape:

  • source: Expression (required)
  • options: Expression (default: null)
  • phase: "source" | "defer" (default: null, excluded from builder function)

Aliases: Standardized, Expression

importNamespaceSpecifier​

JavaScript
t.importNamespaceSpecifier(local);

See also t.isImportNamespaceSpecifier(node, opts) and t.assertImportNamespaceSpecifier(node, opts).

AST Node ImportNamespaceSpecifier shape:

  • local: Identifier (required)

Aliases: Standardized, ModuleSpecifier

importSpecifier​

JavaScript
t.importSpecifier(local, imported);

See also t.isImportSpecifier(node, opts) and t.assertImportSpecifier(node, opts).

AST Node ImportSpecifier shape:

  • local: Identifier (required)
  • imported: Identifier | StringLiteral (required)
  • importKind: "type" | "typeof" | "value" (default: null, excluded from builder function)

Aliases: Standardized, ModuleSpecifier

indexedAccessType​

JavaScript
t.indexedAccessType(objectType, indexType);

See also t.isIndexedAccessType(node, opts) and t.assertIndexedAccessType(node, opts).

AST Node IndexedAccessType shape:

  • objectType: FlowType (required)
  • indexType: FlowType (required)

Aliases: Flow, FlowType

inferredPredicate​

JavaScript
t.inferredPredicate();

See also t.isInferredPredicate(node, opts) and t.assertInferredPredicate(node, opts).

Aliases: Flow, FlowPredicate

interfaceDeclaration​

JavaScript
t.interfaceDeclaration(id, typeParameters, extends, body);

See also t.isInterfaceDeclaration(node, opts) and t.assertInterfaceDeclaration(node, opts).

AST Node InterfaceDeclaration shape:

  • id: Identifier (required)
  • typeParameters: TypeParameterDeclaration (default: null)
  • extends: Array<InterfaceExtends> (default: null)
  • body: ObjectTypeAnnotation (required)

Aliases: Flow, FlowDeclaration, Statement, Declaration

interfaceExtends​

JavaScript
t.interfaceExtends(id, typeParameters);

See also t.isInterfaceExtends(node, opts) and t.assertInterfaceExtends(node, opts).

AST Node InterfaceExtends shape:

  • id: Identifier | QualifiedTypeIdentifier (required)
  • typeParameters: TypeParameterInstantiation (default: null)

Aliases: Flow

interfaceTypeAnnotation​

JavaScript
t.interfaceTypeAnnotation(extends, body);

See also t.isInterfaceTypeAnnotation(node, opts) and t.assertInterfaceTypeAnnotation(node, opts).

AST Node InterfaceTypeAnnotation shape:

  • extends: Array<InterfaceExtends> (default: null)
  • body: ObjectTypeAnnotation (required)

Aliases: Flow, FlowType

interpreterDirective​

JavaScript
t.interpreterDirective(value);

See also t.isInterpreterDirective(node, opts) and t.assertInterpreterDirective(node, opts).

AST Node InterpreterDirective shape:

  • value: string (required)

Aliases: Standardized

intersectionTypeAnnotation​

JavaScript
t.intersectionTypeAnnotation(types);

See also t.isIntersectionTypeAnnotation(node, opts) and t.assertIntersectionTypeAnnotation(node, opts).

AST Node IntersectionTypeAnnotation shape:

  • types: Array<FlowType> (required)

Aliases: Flow, FlowType

jsxAttribute​

JavaScript
t.jsxAttribute(name, value);

See also t.isJSXAttribute(node, opts) and t.assertJSXAttribute(node, opts).

AST Node JSXAttribute shape:

  • name: JSXIdentifier | JSXNamespacedName (required)
  • value: JSXElement | JSXFragment | StringLiteral | JSXExpressionContainer (default: null)

Aliases: JSX, Immutable

jsxClosingElement​

JavaScript
t.jsxClosingElement(name);

See also t.isJSXClosingElement(node, opts) and t.assertJSXClosingElement(node, opts).

AST Node JSXClosingElement shape:

  • name: JSXIdentifier | JSXMemberExpression | JSXNamespacedName (required)

Aliases: JSX, Immutable

jsxClosingFragment​

JavaScript
t.jsxClosingFragment();

See also t.isJSXClosingFragment(node, opts) and t.assertJSXClosingFragment(node, opts).

Aliases: JSX, Immutable

jsxElement​

JavaScript
t.jsxElement(openingElement, closingElement, children, selfClosing);

See also t.isJSXElement(node, opts) and t.assertJSXElement(node, opts).

AST Node JSXElement shape:

  • openingElement: JSXOpeningElement (required)
  • closingElement: JSXClosingElement (default: null)
  • children: Array<JSXText | JSXExpressionContainer | JSXSpreadChild | JSXElement | JSXFragment> (required)
  • selfClosing: boolean (default: null)

Aliases: JSX, Immutable, Expression

jsxEmptyExpression​

JavaScript
t.jsxEmptyExpression();

See also t.isJSXEmptyExpression(node, opts) and t.assertJSXEmptyExpression(node, opts).

Aliases: JSX

jsxExpressionContainer​

JavaScript
t.jsxExpressionContainer(expression);

See also t.isJSXExpressionContainer(node, opts) and t.assertJSXExpressionContainer(node, opts).

AST Node JSXExpressionContainer shape:

  • expression: Expression | JSXEmptyExpression (required)

Aliases: JSX, Immutable

jsxFragment​

JavaScript
t.jsxFragment(openingFragment, closingFragment, children);

See also t.isJSXFragment(node, opts) and t.assertJSXFragment(node, opts).

AST Node JSXFragment shape:

  • openingFragment: JSXOpeningFragment (required)
  • closingFragment: JSXClosingFragment (required)
  • children: Array<JSXText | JSXExpressionContainer | JSXSpreadChild | JSXElement | JSXFragment> (required)

Aliases: JSX, Immutable, Expression

jsxIdentifier​

JavaScript
t.jsxIdentifier(name);

See also t.isJSXIdentifier(node, opts) and t.assertJSXIdentifier(node, opts).

AST Node JSXIdentifier shape:

  • name: string (required)

Aliases: JSX

jsxMemberExpression​

JavaScript
t.jsxMemberExpression(object, property);

See also t.isJSXMemberExpression(node, opts) and t.assertJSXMemberExpression(node, opts).

AST Node JSXMemberExpression shape:

  • object: JSXMemberExpression | JSXIdentifier (required)
  • property: JSXIdentifier (required)

Aliases: JSX

jsxNamespacedName​

JavaScript
t.jsxNamespacedName(namespace, name);

See also t.isJSXNamespacedName(node, opts) and t.assertJSXNamespacedName(node, opts).

AST Node JSXNamespacedName shape:

  • namespace: JSXIdentifier (required)
  • name: JSXIdentifier (required)

Aliases: JSX

jsxOpeningElement​

JavaScript
t.jsxOpeningElement(name, attributes, selfClosing);

See also t.isJSXOpeningElement(node, opts) and t.assertJSXOpeningElement(node, opts).

AST Node JSXOpeningElement shape:

  • name: JSXIdentifier | JSXMemberExpression | JSXNamespacedName (required)
  • attributes: Array<JSXAttribute | JSXSpreadAttribute> (required)
  • selfClosing: boolean (default: false)
  • typeParameters: TypeParameterInstantiation | TSTypeParameterInstantiation (default: null, excluded from builder function)

Aliases: JSX, Immutable

jsxOpeningFragment​

JavaScript
t.jsxOpeningFragment();

See also t.isJSXOpeningFragment(node, opts) and t.assertJSXOpeningFragment(node, opts).

Aliases: JSX, Immutable

jsxSpreadAttribute​

JavaScript
t.jsxSpreadAttribute(argument);

See also t.isJSXSpreadAttribute(node, opts) and t.assertJSXSpreadAttribute(node, opts).

AST Node JSXSpreadAttribute shape:

  • argument: Expression (required)

Aliases: JSX

jsxSpreadChild​

JavaScript
t.jsxSpreadChild(expression);

See also t.isJSXSpreadChild(node, opts) and t.assertJSXSpreadChild(node, opts).

AST Node JSXSpreadChild shape:

  • expression: Expression (required)

Aliases: JSX, Immutable

jsxText​

JavaScript
t.jsxText(value);

See also t.isJSXText(node, opts) and t.assertJSXText(node, opts).

AST Node JSXText shape:

  • value: string (required)

Aliases: JSX, Immutable

labeledStatement​

JavaScript
t.labeledStatement(label, body);

See also t.isLabeledStatement(node, opts) and t.assertLabeledStatement(node, opts).

AST Node LabeledStatement shape:

  • label: Identifier (required)
  • body: Statement (required)

Aliases: Standardized, Statement

logicalExpression​

JavaScript
t.logicalExpression(operator, left, right);

See also t.isLogicalExpression(node, opts) and t.assertLogicalExpression(node, opts).

AST Node LogicalExpression shape:

  • operator: "||" | "&&" | "??" (required)
  • left: Expression (required)
  • right: Expression (required)

Aliases: Standardized, Binary, Expression

memberExpression​

JavaScript
t.memberExpression(object, property, computed, optional);

See also t.isMemberExpression(node, opts) and t.assertMemberExpression(node, opts).

AST Node MemberExpression shape:

  • object: Expression | Super (required)
  • property: if computed then Expression else Identifier (required)
  • computed: boolean (default: false)
  • optional: boolean (default: null)

Aliases: Standardized, Expression, LVal

metaProperty​

JavaScript
t.metaProperty(meta, property);

See also t.isMetaProperty(node, opts) and t.assertMetaProperty(node, opts).

AST Node MetaProperty shape:

  • meta: Identifier (required)
  • property: Identifier (required)

Aliases: Standardized, Expression

mixedTypeAnnotation​

JavaScript
t.mixedTypeAnnotation();

See also t.isMixedTypeAnnotation(node, opts) and t.assertMixedTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

moduleExpression​

JavaScript
t.moduleExpression(body);

See also t.isModuleExpression(node, opts) and t.assertModuleExpression(node, opts).

AST Node ModuleExpression shape:

  • body: Program (required)

Aliases: Expression

newExpression​

JavaScript
t.newExpression(callee, arguments);

See also t.isNewExpression(node, opts) and t.assertNewExpression(node, opts).

AST Node NewExpression shape:

  • callee: Expression | Super | V8IntrinsicIdentifier (required)
  • arguments: Array<Expression | SpreadElement | ArgumentPlaceholder> (required)
  • optional: boolean (default: null, excluded from builder function)
  • typeArguments: TypeParameterInstantiation (default: null, excluded from builder function)
  • typeParameters: TSTypeParameterInstantiation (default: null, excluded from builder function)

Aliases: Standardized, Expression

noop​

JavaScript
t.noop();

See also t.isNoop(node, opts) and t.assertNoop(node, opts).

Aliases: Miscellaneous

nullLiteral​

JavaScript
t.nullLiteral();

See also t.isNullLiteral(node, opts) and t.assertNullLiteral(node, opts).

Aliases: Standardized, Expression, Pureish, Literal, Immutable

nullLiteralTypeAnnotation​

JavaScript
t.nullLiteralTypeAnnotation();

See also t.isNullLiteralTypeAnnotation(node, opts) and t.assertNullLiteralTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

nullableTypeAnnotation​

JavaScript
t.nullableTypeAnnotation(typeAnnotation);

See also t.isNullableTypeAnnotation(node, opts) and t.assertNullableTypeAnnotation(node, opts).

AST Node NullableTypeAnnotation shape:

  • typeAnnotation: FlowType (required)

Aliases: Flow, FlowType

numberLiteralTypeAnnotation​

JavaScript
t.numberLiteralTypeAnnotation(value);

See also t.isNumberLiteralTypeAnnotation(node, opts) and t.assertNumberLiteralTypeAnnotation(node, opts).

AST Node NumberLiteralTypeAnnotation shape:

  • value: number (required)

Aliases: Flow, FlowType

numberTypeAnnotation​

JavaScript
t.numberTypeAnnotation();

See also t.isNumberTypeAnnotation(node, opts) and t.assertNumberTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

numericLiteral​

JavaScript
t.numericLiteral(value);

See also t.isNumericLiteral(node, opts) and t.assertNumericLiteral(node, opts).

AST Node NumericLiteral shape:

  • value: a non-negative finite number (required)

Aliases: Standardized, Expression, Pureish, Literal, Immutable

objectExpression​

JavaScript
t.objectExpression(properties);

See also t.isObjectExpression(node, opts) and t.assertObjectExpression(node, opts).

AST Node ObjectExpression shape:

  • properties: Array<ObjectMethod | ObjectProperty | SpreadElement> (required)

Aliases: Standardized, Expression

objectMethod​

JavaScript
t.objectMethod(kind, key, params, body, computed, generator, async);

See also t.isObjectMethod(node, opts) and t.assertObjectMethod(node, opts).

AST Node ObjectMethod shape:

  • kind: "method" | "get" | "set" (default: 'method')
  • key: if computed then Expression else Identifier | Literal (required)
  • params: Array<Identifier | Pattern | RestElement> (required)
  • body: BlockStatement (required)
  • computed: boolean (default: false)
  • generator: boolean (default: false)
  • async: boolean (default: false)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • returnType: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)
  • typeParameters: TypeParameterDeclaration | TSTypeParameterDeclaration | Noop (default: null, excluded from builder function)

Aliases: Standardized, UserWhitespacable, Function, Scopable, BlockParent, FunctionParent, Method, ObjectMember

objectPattern​

JavaScript
t.objectPattern(properties);

See also t.isObjectPattern(node, opts) and t.assertObjectPattern(node, opts).

AST Node ObjectPattern shape:

  • properties: Array<RestElement | ObjectProperty> (required)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • typeAnnotation: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)

Aliases: Standardized, Pattern, PatternLike, LVal

objectProperty​

JavaScript
t.objectProperty(key, value, computed, shorthand, decorators);

See also t.isObjectProperty(node, opts) and t.assertObjectProperty(node, opts).

AST Node ObjectProperty shape:

  • key: if computed then Expression else Identifier | Literal (required)
  • value: Expression | PatternLike (required)
  • computed: boolean (default: false)
  • shorthand: boolean (default: false)
  • decorators: Array<Decorator> (default: null)

Aliases: Standardized, UserWhitespacable, Property, ObjectMember

objectTypeAnnotation​

JavaScript
t.objectTypeAnnotation(properties, indexers, callProperties, internalSlots, exact);

See also t.isObjectTypeAnnotation(node, opts) and t.assertObjectTypeAnnotation(node, opts).

AST Node ObjectTypeAnnotation shape:

  • properties: Array<ObjectTypeProperty | ObjectTypeSpreadProperty> (required)
  • indexers: Array<ObjectTypeIndexer> (default: [])
  • callProperties: Array<ObjectTypeCallProperty> (default: [])
  • internalSlots: Array<ObjectTypeInternalSlot> (default: [])
  • exact: boolean (default: false)
  • inexact: boolean (default: null, excluded from builder function)

Aliases: Flow, FlowType

objectTypeCallProperty​

JavaScript
t.objectTypeCallProperty(value);

See also t.isObjectTypeCallProperty(node, opts) and t.assertObjectTypeCallProperty(node, opts).

AST Node ObjectTypeCallProperty shape:

  • value: FlowType (required)
  • static: boolean (required)

Aliases: Flow, UserWhitespacable

objectTypeIndexer​

JavaScript
t.objectTypeIndexer(id, key, value, variance);

See also t.isObjectTypeIndexer(node, opts) and t.assertObjectTypeIndexer(node, opts).

AST Node ObjectTypeIndexer shape:

  • id: Identifier (default: null)
  • key: FlowType (required)
  • value: FlowType (required)
  • variance: Variance (default: null)
  • static: boolean (required)

Aliases: Flow, UserWhitespacable

objectTypeInternalSlot​

JavaScript
t.objectTypeInternalSlot(id, value, optional, static, method);

See also t.isObjectTypeInternalSlot(node, opts) and t.assertObjectTypeInternalSlot(node, opts).

AST Node ObjectTypeInternalSlot shape:

  • id: Identifier (required)
  • value: FlowType (required)
  • optional: boolean (required)
  • static: boolean (required)
  • method: boolean (required)

Aliases: Flow, UserWhitespacable

objectTypeProperty​

JavaScript
t.objectTypeProperty(key, value, variance);

See also t.isObjectTypeProperty(node, opts) and t.assertObjectTypeProperty(node, opts).

AST Node ObjectTypeProperty shape:

  • key: Identifier | StringLiteral (required)
  • value: FlowType (required)
  • variance: Variance (default: null)
  • kind: "init" | "get" | "set" (required)
  • method: boolean (required)
  • optional: boolean (required)
  • proto: boolean (required)
  • static: boolean (required)

Aliases: Flow, UserWhitespacable

objectTypeSpreadProperty​

JavaScript
t.objectTypeSpreadProperty(argument);

See also t.isObjectTypeSpreadProperty(node, opts) and t.assertObjectTypeSpreadProperty(node, opts).

AST Node ObjectTypeSpreadProperty shape:

  • argument: FlowType (required)

Aliases: Flow, UserWhitespacable

opaqueType​

JavaScript
t.opaqueType(id, typeParameters, supertype, impltype);

See also t.isOpaqueType(node, opts) and t.assertOpaqueType(node, opts).

AST Node OpaqueType shape:

  • id: Identifier (required)
  • typeParameters: TypeParameterDeclaration (default: null)
  • supertype: FlowType (default: null)
  • impltype: FlowType (required)

Aliases: Flow, FlowDeclaration, Statement, Declaration

optionalCallExpression​

JavaScript
t.optionalCallExpression(callee, arguments, optional);

See also t.isOptionalCallExpression(node, opts) and t.assertOptionalCallExpression(node, opts).

AST Node OptionalCallExpression shape:

  • callee: Expression (required)
  • arguments: Array<Expression | SpreadElement | ArgumentPlaceholder> (required)
  • optional: boolean (required)
  • typeArguments: TypeParameterInstantiation (default: null, excluded from builder function)
  • typeParameters: TSTypeParameterInstantiation (default: null, excluded from builder function)

Aliases: Standardized, Expression

optionalIndexedAccessType​

JavaScript
t.optionalIndexedAccessType(objectType, indexType);

See also t.isOptionalIndexedAccessType(node, opts) and t.assertOptionalIndexedAccessType(node, opts).

AST Node OptionalIndexedAccessType shape:

  • objectType: FlowType (required)
  • indexType: FlowType (required)
  • optional: boolean (required)

Aliases: Flow, FlowType

optionalMemberExpression​

JavaScript
t.optionalMemberExpression(object, property, computed, optional);

See also t.isOptionalMemberExpression(node, opts) and t.assertOptionalMemberExpression(node, opts).

AST Node OptionalMemberExpression shape:

  • object: Expression (required)
  • property: Expression | Identifier (required)
  • computed: boolean (default: false)
  • optional: boolean (required)

Aliases: Standardized, Expression

parenthesizedExpression​

JavaScript
t.parenthesizedExpression(expression);

See also t.isParenthesizedExpression(node, opts) and t.assertParenthesizedExpression(node, opts).

AST Node ParenthesizedExpression shape:

  • expression: Expression (required)

Aliases: Standardized, Expression, ExpressionWrapper

pipelineBareFunction​

JavaScript
t.pipelineBareFunction(callee);

See also t.isPipelineBareFunction(node, opts) and t.assertPipelineBareFunction(node, opts).

AST Node PipelineBareFunction shape:

  • callee: Expression (required)

Aliases: Expression

pipelinePrimaryTopicReference​

JavaScript
t.pipelinePrimaryTopicReference();

See also t.isPipelinePrimaryTopicReference(node, opts) and t.assertPipelinePrimaryTopicReference(node, opts).

Aliases: Expression

pipelineTopicExpression​

JavaScript
t.pipelineTopicExpression(expression);

See also t.isPipelineTopicExpression(node, opts) and t.assertPipelineTopicExpression(node, opts).

AST Node PipelineTopicExpression shape:

  • expression: Expression (required)

Aliases: Expression

placeholder​

JavaScript
t.placeholder(expectedNode, name);

See also t.isPlaceholder(node, opts) and t.assertPlaceholder(node, opts).

AST Node Placeholder shape:

  • expectedNode: "Identifier" | "StringLiteral" | "Expression" | "Statement" | "Declaration" | "BlockStatement" | "ClassBody" | "Pattern" (required)
  • name: Identifier (required)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • typeAnnotation: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)

Aliases: Miscellaneous

privateName​

JavaScript
t.privateName(id);

See also t.isPrivateName(node, opts) and t.assertPrivateName(node, opts).

AST Node PrivateName shape:

  • id: Identifier (required)

Aliases: Standardized, Private

program​

JavaScript
t.program(body, directives, sourceType, interpreter);

See also t.isProgram(node, opts) and t.assertProgram(node, opts).

AST Node Program shape:

  • body: Array<Statement> (required)
  • directives: Array<Directive> (default: [])
  • sourceType: "script" | "module" (default: 'script')
  • interpreter: InterpreterDirective (default: null)

Aliases: Standardized, Scopable, BlockParent, Block

qualifiedTypeIdentifier​

JavaScript
t.qualifiedTypeIdentifier(id, qualification);

See also t.isQualifiedTypeIdentifier(node, opts) and t.assertQualifiedTypeIdentifier(node, opts).

AST Node QualifiedTypeIdentifier shape:

  • id: Identifier (required)
  • qualification: Identifier | QualifiedTypeIdentifier (required)

Aliases: Flow

recordExpression​

JavaScript
t.recordExpression(properties);

See also t.isRecordExpression(node, opts) and t.assertRecordExpression(node, opts).

AST Node RecordExpression shape:

  • properties: Array<ObjectProperty | SpreadElement> (required)

Aliases: Expression

regExpLiteral​

JavaScript
t.regExpLiteral(pattern, flags);

See also t.isRegExpLiteral(node, opts) and t.assertRegExpLiteral(node, opts).

AST Node RegExpLiteral shape:

  • pattern: string (required)
  • flags: string (default: '')

Aliases: Standardized, Expression, Pureish, Literal

restElement​

JavaScript
t.restElement(argument);

See also t.isRestElement(node, opts) and t.assertRestElement(node, opts).

AST Node RestElement shape:

  • argument: LVal (required)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • typeAnnotation: TypeAnnotation | TSTypeAnnotation | Noop (default: null, excluded from builder function)

Aliases: Standardized, LVal, PatternLike

returnStatement​

JavaScript
t.returnStatement(argument);

See also t.isReturnStatement(node, opts) and t.assertReturnStatement(node, opts).

AST Node ReturnStatement shape:

  • argument: Expression (default: null)

Aliases: Standardized, Statement, Terminatorless, CompletionStatement

sequenceExpression​

JavaScript
t.sequenceExpression(expressions);

See also t.isSequenceExpression(node, opts) and t.assertSequenceExpression(node, opts).

AST Node SequenceExpression shape:

  • expressions: Array<Expression> (required)

Aliases: Standardized, Expression

spreadElement​

JavaScript
t.spreadElement(argument);

See also t.isSpreadElement(node, opts) and t.assertSpreadElement(node, opts).

AST Node SpreadElement shape:

  • argument: Expression (required)

Aliases: Standardized, UnaryLike

staticBlock​

JavaScript
t.staticBlock(body);

See also t.isStaticBlock(node, opts) and t.assertStaticBlock(node, opts).

AST Node StaticBlock shape:

  • body: Array<Statement> (required)

Aliases: Standardized, Scopable, BlockParent, FunctionParent

stringLiteral​

JavaScript
t.stringLiteral(value);

See also t.isStringLiteral(node, opts) and t.assertStringLiteral(node, opts).

AST Node StringLiteral shape:

  • value: string (required)

Aliases: Standardized, Expression, Pureish, Literal, Immutable

stringLiteralTypeAnnotation​

JavaScript
t.stringLiteralTypeAnnotation(value);

See also t.isStringLiteralTypeAnnotation(node, opts) and t.assertStringLiteralTypeAnnotation(node, opts).

AST Node StringLiteralTypeAnnotation shape:

  • value: string (required)

Aliases: Flow, FlowType

stringTypeAnnotation​

JavaScript
t.stringTypeAnnotation();

See also t.isStringTypeAnnotation(node, opts) and t.assertStringTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

super​

JavaScript
t.super();

See also t.isSuper(node, opts) and t.assertSuper(node, opts).

Aliases: Standardized, Expression

switchCase​

JavaScript
t.switchCase(test, consequent);

See also t.isSwitchCase(node, opts) and t.assertSwitchCase(node, opts).

AST Node SwitchCase shape:

  • test: Expression (default: null)
  • consequent: Array<Statement> (required)

Aliases: Standardized

switchStatement​

JavaScript
t.switchStatement(discriminant, cases);

See also t.isSwitchStatement(node, opts) and t.assertSwitchStatement(node, opts).

AST Node SwitchStatement shape:

  • discriminant: Expression (required)
  • cases: Array<SwitchCase> (required)

Aliases: Standardized, Statement, BlockParent, Scopable

symbolTypeAnnotation​

JavaScript
t.symbolTypeAnnotation();

See also t.isSymbolTypeAnnotation(node, opts) and t.assertSymbolTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

tsAnyKeyword​

JavaScript
t.tsAnyKeyword();

See also t.isTSAnyKeyword(node, opts) and t.assertTSAnyKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsArrayType​

JavaScript
t.tsArrayType(elementType);

See also t.isTSArrayType(node, opts) and t.assertTSArrayType(node, opts).

AST Node TSArrayType shape:

  • elementType: TSType (required)

Aliases: TypeScript, TSType

tsAsExpression​

JavaScript
t.tsAsExpression(expression, typeAnnotation);

See also t.isTSAsExpression(node, opts) and t.assertTSAsExpression(node, opts).

AST Node TSAsExpression shape:

  • expression: Expression (required)
  • typeAnnotation: TSType (required)

Aliases: TypeScript, Expression, LVal, PatternLike

tsBigIntKeyword​

JavaScript
t.tsBigIntKeyword();

See also t.isTSBigIntKeyword(node, opts) and t.assertTSBigIntKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsBooleanKeyword​

JavaScript
t.tsBooleanKeyword();

See also t.isTSBooleanKeyword(node, opts) and t.assertTSBooleanKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsCallSignatureDeclaration​

JavaScript
t.tsCallSignatureDeclaration(typeParameters, parameters, typeAnnotation);

See also t.isTSCallSignatureDeclaration(node, opts) and t.assertTSCallSignatureDeclaration(node, opts).

AST Node TSCallSignatureDeclaration shape:

  • typeParameters: TSTypeParameterDeclaration (default: null)
  • parameters: Array<ArrayPattern | Identifier | ObjectPattern | RestElement> (required)
  • typeAnnotation: TSTypeAnnotation (default: null)

Aliases: TypeScript, TSTypeElement

tsConditionalType​

JavaScript
t.tsConditionalType(checkType, extendsType, trueType, falseType);

See also t.isTSConditionalType(node, opts) and t.assertTSConditionalType(node, opts).

AST Node TSConditionalType shape:

  • checkType: TSType (required)
  • extendsType: TSType (required)
  • trueType: TSType (required)
  • falseType: TSType (required)

Aliases: TypeScript, TSType

tsConstructSignatureDeclaration​

JavaScript
t.tsConstructSignatureDeclaration(typeParameters, parameters, typeAnnotation);

See also t.isTSConstructSignatureDeclaration(node, opts) and t.assertTSConstructSignatureDeclaration(node, opts).

AST Node TSConstructSignatureDeclaration shape:

  • typeParameters: TSTypeParameterDeclaration (default: null)
  • parameters: Array<ArrayPattern | Identifier | ObjectPattern | RestElement> (required)
  • typeAnnotation: TSTypeAnnotation (default: null)

Aliases: TypeScript, TSTypeElement

tsConstructorType​

JavaScript
t.tsConstructorType(typeParameters, parameters, typeAnnotation);

See also t.isTSConstructorType(node, opts) and t.assertTSConstructorType(node, opts).

AST Node TSConstructorType shape:

  • typeParameters: TSTypeParameterDeclaration (default: null)
  • parameters: Array<ArrayPattern | Identifier | ObjectPattern | RestElement> (required)
  • typeAnnotation: TSTypeAnnotation (default: null)
  • abstract: boolean (default: null, excluded from builder function)

Aliases: TypeScript, TSType

tsDeclareFunction​

JavaScript
t.tsDeclareFunction(id, typeParameters, params, returnType);

See also t.isTSDeclareFunction(node, opts) and t.assertTSDeclareFunction(node, opts).

AST Node TSDeclareFunction shape:

  • id: Identifier (default: null)
  • typeParameters: TSTypeParameterDeclaration | Noop (default: null)
  • params: Array<Identifier | Pattern | RestElement> (required)
  • returnType: TSTypeAnnotation | Noop (default: null)
  • async: boolean (default: false, excluded from builder function)
  • declare: boolean (default: null, excluded from builder function)
  • generator: boolean (default: false, excluded from builder function)

Aliases: TypeScript, Statement, Declaration

tsDeclareMethod​

JavaScript
t.tsDeclareMethod(decorators, key, typeParameters, params, returnType);

See also t.isTSDeclareMethod(node, opts) and t.assertTSDeclareMethod(node, opts).

AST Node TSDeclareMethod shape:

  • decorators: Array<Decorator> (default: null)
  • key: Identifier | StringLiteral | NumericLiteral | BigIntLiteral | Expression (required)
  • typeParameters: TSTypeParameterDeclaration | Noop (default: null)
  • params: Array<Identifier | Pattern | RestElement | TSParameterProperty> (required)
  • returnType: TSTypeAnnotation | Noop (default: null)
  • abstract: boolean (default: null, excluded from builder function)
  • access: "public" | "private" | "protected" (default: null, excluded from builder function)
  • accessibility: "public" | "private" | "protected" (default: null, excluded from builder function)
  • async: boolean (default: false, excluded from builder function)
  • computed: boolean (default: false, excluded from builder function)
  • generator: boolean (default: false, excluded from builder function)
  • kind: "get" | "set" | "method" | "constructor" (default: 'method', excluded from builder function)
  • optional: boolean (default: null, excluded from builder function)
  • override: boolean (default: false, excluded from builder function)
  • static: boolean (default: false, excluded from builder function)

Aliases: TypeScript

tsEnumDeclaration​

JavaScript
t.tsEnumDeclaration(id, members);

See also t.isTSEnumDeclaration(node, opts) and t.assertTSEnumDeclaration(node, opts).

AST Node TSEnumDeclaration shape:

  • id: Identifier (required)
  • members: Array<TSEnumMember> (required)
  • const: boolean (default: null, excluded from builder function)
  • declare: boolean (default: null, excluded from builder function)
  • initializer: Expression (default: null, excluded from builder function)

Aliases: TypeScript, Statement, Declaration

tsEnumMember​

JavaScript
t.tsEnumMember(id, initializer);

See also t.isTSEnumMember(node, opts) and t.assertTSEnumMember(node, opts).

AST Node TSEnumMember shape:

  • id: Identifier | StringLiteral (required)
  • initializer: Expression (default: null)

Aliases: TypeScript

tsExportAssignment​

JavaScript
t.tsExportAssignment(expression);

See also t.isTSExportAssignment(node, opts) and t.assertTSExportAssignment(node, opts).

AST Node TSExportAssignment shape:

  • expression: Expression (required)

Aliases: TypeScript, Statement

tsExpressionWithTypeArguments​

JavaScript
t.tsExpressionWithTypeArguments(expression, typeParameters);

See also t.isTSExpressionWithTypeArguments(node, opts) and t.assertTSExpressionWithTypeArguments(node, opts).

AST Node TSExpressionWithTypeArguments shape:

  • expression: TSEntityName (required)
  • typeParameters: TSTypeParameterInstantiation (default: null)

Aliases: TypeScript, TSType

tsExternalModuleReference​

JavaScript
t.tsExternalModuleReference(expression);

See also t.isTSExternalModuleReference(node, opts) and t.assertTSExternalModuleReference(node, opts).

AST Node TSExternalModuleReference shape:

  • expression: StringLiteral (required)

Aliases: TypeScript

tsFunctionType​

JavaScript
t.tsFunctionType(typeParameters, parameters, typeAnnotation);

See also t.isTSFunctionType(node, opts) and t.assertTSFunctionType(node, opts).

AST Node TSFunctionType shape:

  • typeParameters: TSTypeParameterDeclaration (default: null)
  • parameters: Array<ArrayPattern | Identifier | ObjectPattern | RestElement> (required)
  • typeAnnotation: TSTypeAnnotation (default: null)

Aliases: TypeScript, TSType

tsImportEqualsDeclaration​

JavaScript
t.tsImportEqualsDeclaration(id, moduleReference);

See also t.isTSImportEqualsDeclaration(node, opts) and t.assertTSImportEqualsDeclaration(node, opts).

AST Node TSImportEqualsDeclaration shape:

  • id: Identifier (required)
  • moduleReference: TSEntityName | TSExternalModuleReference (required)
  • importKind: "type" | "value" (default: null, excluded from builder function)
  • isExport: boolean (required)

Aliases: TypeScript, Statement

tsImportType​

JavaScript
t.tsImportType(argument, qualifier, typeParameters);

See also t.isTSImportType(node, opts) and t.assertTSImportType(node, opts).

AST Node TSImportType shape:

  • argument: StringLiteral (required)
  • qualifier: TSEntityName (default: null)
  • typeParameters: TSTypeParameterInstantiation (default: null)
  • options: Expression (default: null, excluded from builder function)

Aliases: TypeScript, TSType

tsIndexSignature​

JavaScript
t.tsIndexSignature(parameters, typeAnnotation);

See also t.isTSIndexSignature(node, opts) and t.assertTSIndexSignature(node, opts).

AST Node TSIndexSignature shape:

  • parameters: Array<Identifier> (required)
  • typeAnnotation: TSTypeAnnotation (default: null)
  • readonly: boolean (default: null, excluded from builder function)
  • static: boolean (default: null, excluded from builder function)

Aliases: TypeScript, TSTypeElement

tsIndexedAccessType​

JavaScript
t.tsIndexedAccessType(objectType, indexType);

See also t.isTSIndexedAccessType(node, opts) and t.assertTSIndexedAccessType(node, opts).

AST Node TSIndexedAccessType shape:

  • objectType: TSType (required)
  • indexType: TSType (required)

Aliases: TypeScript, TSType

tsInferType​

JavaScript
t.tsInferType(typeParameter);

See also t.isTSInferType(node, opts) and t.assertTSInferType(node, opts).

AST Node TSInferType shape:

  • typeParameter: TSTypeParameter (required)

Aliases: TypeScript, TSType

tsInstantiationExpression​

JavaScript
t.tsInstantiationExpression(expression, typeParameters);

See also t.isTSInstantiationExpression(node, opts) and t.assertTSInstantiationExpression(node, opts).

AST Node TSInstantiationExpression shape:

  • expression: Expression (required)
  • typeParameters: TSTypeParameterInstantiation (default: null)

Aliases: TypeScript, Expression

tsInterfaceBody​

JavaScript
t.tsInterfaceBody(body);

See also t.isTSInterfaceBody(node, opts) and t.assertTSInterfaceBody(node, opts).

AST Node TSInterfaceBody shape:

  • body: Array<TSTypeElement> (required)

Aliases: TypeScript

tsInterfaceDeclaration​

JavaScript
t.tsInterfaceDeclaration(id, typeParameters, extends, body);

See also t.isTSInterfaceDeclaration(node, opts) and t.assertTSInterfaceDeclaration(node, opts).

AST Node TSInterfaceDeclaration shape:

  • id: Identifier (required)
  • typeParameters: TSTypeParameterDeclaration (default: null)
  • extends: Array<TSExpressionWithTypeArguments> (default: null)
  • body: TSInterfaceBody (required)
  • declare: boolean (default: null, excluded from builder function)

Aliases: TypeScript, Statement, Declaration

tsIntersectionType​

JavaScript
t.tsIntersectionType(types);

See also t.isTSIntersectionType(node, opts) and t.assertTSIntersectionType(node, opts).

AST Node TSIntersectionType shape:

  • types: Array<TSType> (required)

Aliases: TypeScript, TSType

tsIntrinsicKeyword​

JavaScript
t.tsIntrinsicKeyword();

See also t.isTSIntrinsicKeyword(node, opts) and t.assertTSIntrinsicKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsLiteralType​

JavaScript
t.tsLiteralType(literal);

See also t.isTSLiteralType(node, opts) and t.assertTSLiteralType(node, opts).

AST Node TSLiteralType shape:

  • literal: NumericLiteral | StringLiteral | BooleanLiteral | BigIntLiteral | TemplateLiteral | UnaryExpression (required)

Aliases: TypeScript, TSType, TSBaseType

tsMappedType​

JavaScript
t.tsMappedType(typeParameter, typeAnnotation, nameType);

See also t.isTSMappedType(node, opts) and t.assertTSMappedType(node, opts).

AST Node TSMappedType shape:

  • typeParameter: TSTypeParameter (required)
  • typeAnnotation: TSType (default: null)
  • nameType: TSType (default: null)
  • optional: true | false | "+" | "-" (default: null, excluded from builder function)
  • readonly: true | false | "+" | "-" (default: null, excluded from builder function)

Aliases: TypeScript, TSType

tsMethodSignature​

JavaScript
t.tsMethodSignature(key, typeParameters, parameters, typeAnnotation);

See also t.isTSMethodSignature(node, opts) and t.assertTSMethodSignature(node, opts).

AST Node TSMethodSignature shape:

  • key: Expression (required)
  • typeParameters: TSTypeParameterDeclaration (default: null)
  • parameters: Array<ArrayPattern | Identifier | ObjectPattern | RestElement> (required)
  • typeAnnotation: TSTypeAnnotation (default: null)
  • computed: boolean (default: false, excluded from builder function)
  • kind: "method" | "get" | "set" (required)
  • optional: boolean (default: null, excluded from builder function)

Aliases: TypeScript, TSTypeElement

tsModuleBlock​

JavaScript
t.tsModuleBlock(body);

See also t.isTSModuleBlock(node, opts) and t.assertTSModuleBlock(node, opts).

AST Node TSModuleBlock shape:

  • body: Array<Statement> (required)

Aliases: TypeScript, Scopable, Block, BlockParent, FunctionParent

tsModuleDeclaration​

JavaScript
t.tsModuleDeclaration(id, body);

See also t.isTSModuleDeclaration(node, opts) and t.assertTSModuleDeclaration(node, opts).

AST Node TSModuleDeclaration shape:

  • id: Identifier | StringLiteral (required)
  • body: TSModuleBlock | TSModuleDeclaration (required)
  • declare: boolean (default: null, excluded from builder function)
  • global: boolean (default: null, excluded from builder function)
  • kind: "global" | "module" | "namespace" (required)

Aliases: TypeScript, Statement, Declaration

tsNamedTupleMember​

JavaScript
t.tsNamedTupleMember(label, elementType, optional);

See also t.isTSNamedTupleMember(node, opts) and t.assertTSNamedTupleMember(node, opts).

AST Node TSNamedTupleMember shape:

  • label: Identifier (required)
  • elementType: TSType (required)
  • optional: boolean (default: false)

Aliases: TypeScript

tsNamespaceExportDeclaration​

JavaScript
t.tsNamespaceExportDeclaration(id);

See also t.isTSNamespaceExportDeclaration(node, opts) and t.assertTSNamespaceExportDeclaration(node, opts).

AST Node TSNamespaceExportDeclaration shape:

  • id: Identifier (required)

Aliases: TypeScript, Statement

tsNeverKeyword​

JavaScript
t.tsNeverKeyword();

See also t.isTSNeverKeyword(node, opts) and t.assertTSNeverKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsNonNullExpression​

JavaScript
t.tsNonNullExpression(expression);

See also t.isTSNonNullExpression(node, opts) and t.assertTSNonNullExpression(node, opts).

AST Node TSNonNullExpression shape:

  • expression: Expression (required)

Aliases: TypeScript, Expression, LVal, PatternLike

tsNullKeyword​

JavaScript
t.tsNullKeyword();

See also t.isTSNullKeyword(node, opts) and t.assertTSNullKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsNumberKeyword​

JavaScript
t.tsNumberKeyword();

See also t.isTSNumberKeyword(node, opts) and t.assertTSNumberKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsObjectKeyword​

JavaScript
t.tsObjectKeyword();

See also t.isTSObjectKeyword(node, opts) and t.assertTSObjectKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsOptionalType​

JavaScript
t.tsOptionalType(typeAnnotation);

See also t.isTSOptionalType(node, opts) and t.assertTSOptionalType(node, opts).

AST Node TSOptionalType shape:

  • typeAnnotation: TSType (required)

Aliases: TypeScript, TSType

tsParameterProperty​

JavaScript
t.tsParameterProperty(parameter);

See also t.isTSParameterProperty(node, opts) and t.assertTSParameterProperty(node, opts).

AST Node TSParameterProperty shape:

  • parameter: Identifier | AssignmentPattern (required)
  • accessibility: "public" | "private" | "protected" (default: null, excluded from builder function)
  • decorators: Array<Decorator> (default: null, excluded from builder function)
  • override: boolean (default: null, excluded from builder function)
  • readonly: boolean (default: null, excluded from builder function)

Aliases: TypeScript, LVal

tsParenthesizedType​

JavaScript
t.tsParenthesizedType(typeAnnotation);

See also t.isTSParenthesizedType(node, opts) and t.assertTSParenthesizedType(node, opts).

AST Node TSParenthesizedType shape:

  • typeAnnotation: TSType (required)

Aliases: TypeScript, TSType

tsPropertySignature​

JavaScript
t.tsPropertySignature(key, typeAnnotation);

See also t.isTSPropertySignature(node, opts) and t.assertTSPropertySignature(node, opts).

AST Node TSPropertySignature shape:

  • key: Expression (required)
  • typeAnnotation: TSTypeAnnotation (default: null)
  • computed: boolean (default: false, excluded from builder function)
  • kind: "get" | "set" (required)
  • optional: boolean (default: null, excluded from builder function)
  • readonly: boolean (default: null, excluded from builder function)

Aliases: TypeScript, TSTypeElement

tsQualifiedName​

JavaScript
t.tsQualifiedName(left, right);

See also t.isTSQualifiedName(node, opts) and t.assertTSQualifiedName(node, opts).

AST Node TSQualifiedName shape:

  • left: TSEntityName (required)
  • right: Identifier (required)

Aliases: TypeScript, TSEntityName

tsRestType​

JavaScript
t.tsRestType(typeAnnotation);

See also t.isTSRestType(node, opts) and t.assertTSRestType(node, opts).

AST Node TSRestType shape:

  • typeAnnotation: TSType (required)

Aliases: TypeScript, TSType

tsSatisfiesExpression​

JavaScript
t.tsSatisfiesExpression(expression, typeAnnotation);
History
VersionChanges
v7.20.0Introduced

See also t.isTSSatisfiesExpression(node, opts) and t.assertTSSatisfiesExpression(node, opts).

AST Node TSSatisfiesExpression shape:

  • expression: Expression (required)
  • typeAnnotation: TSType (required)

Aliases: TypeScript, Expression, LVal, PatternLike

tsStringKeyword​

JavaScript
t.tsStringKeyword();

See also t.isTSStringKeyword(node, opts) and t.assertTSStringKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsSymbolKeyword​

JavaScript
t.tsSymbolKeyword();

See also t.isTSSymbolKeyword(node, opts) and t.assertTSSymbolKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsThisType​

JavaScript
t.tsThisType();

See also t.isTSThisType(node, opts) and t.assertTSThisType(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsTupleType​

JavaScript
t.tsTupleType(elementTypes);

See also t.isTSTupleType(node, opts) and t.assertTSTupleType(node, opts).

AST Node TSTupleType shape:

  • elementTypes: Array<TSType | TSNamedTupleMember> (required)

Aliases: TypeScript, TSType

tsTypeAliasDeclaration​

JavaScript
t.tsTypeAliasDeclaration(id, typeParameters, typeAnnotation);

See also t.isTSTypeAliasDeclaration(node, opts) and t.assertTSTypeAliasDeclaration(node, opts).

AST Node TSTypeAliasDeclaration shape:

  • id: Identifier (required)
  • typeParameters: TSTypeParameterDeclaration (default: null)
  • typeAnnotation: TSType (required)
  • declare: boolean (default: null, excluded from builder function)

Aliases: TypeScript, Statement, Declaration

tsTypeAnnotation​

JavaScript
t.tsTypeAnnotation(typeAnnotation);

See also t.isTSTypeAnnotation(node, opts) and t.assertTSTypeAnnotation(node, opts).

AST Node TSTypeAnnotation shape:

  • typeAnnotation: TSType (required)

Aliases: TypeScript

tsTypeAssertion​

JavaScript
t.tsTypeAssertion(typeAnnotation, expression);

See also t.isTSTypeAssertion(node, opts) and t.assertTSTypeAssertion(node, opts).

AST Node TSTypeAssertion shape:

  • typeAnnotation: TSType (required)
  • expression: Expression (required)

Aliases: TypeScript, Expression, LVal, PatternLike

tsTypeLiteral​

JavaScript
t.tsTypeLiteral(members);

See also t.isTSTypeLiteral(node, opts) and t.assertTSTypeLiteral(node, opts).

AST Node TSTypeLiteral shape:

  • members: Array<TSTypeElement> (required)

Aliases: TypeScript, TSType

tsTypeOperator​

JavaScript
t.tsTypeOperator(typeAnnotation);

See also t.isTSTypeOperator(node, opts) and t.assertTSTypeOperator(node, opts).

AST Node TSTypeOperator shape:

  • typeAnnotation: TSType (required)
  • operator: string (required)

Aliases: TypeScript, TSType

tsTypeParameter​

JavaScript
t.tsTypeParameter(constraint, default, name);
History
VersionChanges
v7.21.0Supports const

See also t.isTSTypeParameter(node, opts) and t.assertTSTypeParameter(node, opts).

AST Node TSTypeParameter shape:

  • constraint: TSType (default: null)
  • default: TSType (default: null)
  • name: string (required)
  • const: boolean (default: null, excluded from builder function)
  • in: boolean (default: null, excluded from builder function)
  • out: boolean (default: null, excluded from builder function)

Aliases: TypeScript

tsTypeParameterDeclaration​

JavaScript
t.tsTypeParameterDeclaration(params);

See also t.isTSTypeParameterDeclaration(node, opts) and t.assertTSTypeParameterDeclaration(node, opts).

AST Node TSTypeParameterDeclaration shape:

  • params: Array<TSTypeParameter> (required)

Aliases: TypeScript

tsTypeParameterInstantiation​

JavaScript
t.tsTypeParameterInstantiation(params);

See also t.isTSTypeParameterInstantiation(node, opts) and t.assertTSTypeParameterInstantiation(node, opts).

AST Node TSTypeParameterInstantiation shape:

  • params: Array<TSType> (required)

Aliases: TypeScript

tsTypePredicate​

JavaScript
t.tsTypePredicate(parameterName, typeAnnotation, asserts);

See also t.isTSTypePredicate(node, opts) and t.assertTSTypePredicate(node, opts).

AST Node TSTypePredicate shape:

  • parameterName: Identifier | TSThisType (required)
  • typeAnnotation: TSTypeAnnotation (default: null)
  • asserts: boolean (default: null)

Aliases: TypeScript, TSType

tsTypeQuery​

JavaScript
t.tsTypeQuery(exprName, typeParameters);

See also t.isTSTypeQuery(node, opts) and t.assertTSTypeQuery(node, opts).

AST Node TSTypeQuery shape:

  • exprName: TSEntityName | TSImportType (required)
  • typeParameters: TSTypeParameterInstantiation (default: null)

Aliases: TypeScript, TSType

tsTypeReference​

JavaScript
t.tsTypeReference(typeName, typeParameters);

See also t.isTSTypeReference(node, opts) and t.assertTSTypeReference(node, opts).

AST Node TSTypeReference shape:

  • typeName: TSEntityName (required)
  • typeParameters: TSTypeParameterInstantiation (default: null)

Aliases: TypeScript, TSType

tsUndefinedKeyword​

JavaScript
t.tsUndefinedKeyword();

See also t.isTSUndefinedKeyword(node, opts) and t.assertTSUndefinedKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsUnionType​

JavaScript
t.tsUnionType(types);

See also t.isTSUnionType(node, opts) and t.assertTSUnionType(node, opts).

AST Node TSUnionType shape:

  • types: Array<TSType> (required)

Aliases: TypeScript, TSType

tsUnknownKeyword​

JavaScript
t.tsUnknownKeyword();

See also t.isTSUnknownKeyword(node, opts) and t.assertTSUnknownKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

tsVoidKeyword​

JavaScript
t.tsVoidKeyword();

See also t.isTSVoidKeyword(node, opts) and t.assertTSVoidKeyword(node, opts).

Aliases: TypeScript, TSType, TSBaseType

taggedTemplateExpression​

JavaScript
t.taggedTemplateExpression(tag, quasi);

See also t.isTaggedTemplateExpression(node, opts) and t.assertTaggedTemplateExpression(node, opts).

AST Node TaggedTemplateExpression shape:

  • tag: Expression (required)
  • quasi: TemplateLiteral (required)
  • typeParameters: TypeParameterInstantiation | TSTypeParameterInstantiation (default: null, excluded from builder function)

Aliases: Standardized, Expression

templateElement​

JavaScript
t.templateElement(value, tail);

See also t.isTemplateElement(node, opts) and t.assertTemplateElement(node, opts).

AST Node TemplateElement shape:

  • value: { raw: string, cooked?: string } (required)
  • tail: boolean (default: false)

Aliases: Standardized

templateLiteral​

JavaScript
t.templateLiteral(quasis, expressions);

See also t.isTemplateLiteral(node, opts) and t.assertTemplateLiteral(node, opts).

AST Node TemplateLiteral shape:

  • quasis: Array<TemplateElement> (required)
  • expressions: Array<Expression | TSType> (required)

Aliases: Standardized, Expression, Literal

thisExpression​

JavaScript
t.thisExpression();

See also t.isThisExpression(node, opts) and t.assertThisExpression(node, opts).

Aliases: Standardized, Expression

thisTypeAnnotation​

JavaScript
t.thisTypeAnnotation();

See also t.isThisTypeAnnotation(node, opts) and t.assertThisTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

throwStatement​

JavaScript
t.throwStatement(argument);

See also t.isThrowStatement(node, opts) and t.assertThrowStatement(node, opts).

AST Node ThrowStatement shape:

  • argument: Expression (required)

Aliases: Standardized, Statement, Terminatorless, CompletionStatement

topicReference​

JavaScript
t.topicReference();

See also t.isTopicReference(node, opts) and t.assertTopicReference(node, opts).

Aliases: Expression

tryStatement​

JavaScript
t.tryStatement(block, handler, finalizer);

See also t.isTryStatement(node, opts) and t.assertTryStatement(node, opts).

AST Node TryStatement shape:

  • block: BlockStatement (required)
  • handler: CatchClause (default: null)
  • finalizer: BlockStatement (default: null)

Aliases: Standardized, Statement

tupleExpression​

JavaScript
t.tupleExpression(elements);

See also t.isTupleExpression(node, opts) and t.assertTupleExpression(node, opts).

AST Node TupleExpression shape:

  • elements: Array<Expression | SpreadElement> (default: [])

Aliases: Expression

tupleTypeAnnotation​

JavaScript
t.tupleTypeAnnotation(types);

See also t.isTupleTypeAnnotation(node, opts) and t.assertTupleTypeAnnotation(node, opts).

AST Node TupleTypeAnnotation shape:

  • types: Array<FlowType> (required)

Aliases: Flow, FlowType

typeAlias​

JavaScript
t.typeAlias(id, typeParameters, right);

See also t.isTypeAlias(node, opts) and t.assertTypeAlias(node, opts).

AST Node TypeAlias shape:

  • id: Identifier (required)
  • typeParameters: TypeParameterDeclaration (default: null)
  • right: FlowType (required)

Aliases: Flow, FlowDeclaration, Statement, Declaration

typeAnnotation​

JavaScript
t.typeAnnotation(typeAnnotation);

See also t.isTypeAnnotation(node, opts) and t.assertTypeAnnotation(node, opts).

AST Node TypeAnnotation shape:

  • typeAnnotation: FlowType (required)

Aliases: Flow

typeCastExpression​

JavaScript
t.typeCastExpression(expression, typeAnnotation);

See also t.isTypeCastExpression(node, opts) and t.assertTypeCastExpression(node, opts).

AST Node TypeCastExpression shape:

  • expression: Expression (required)
  • typeAnnotation: TypeAnnotation (required)

Aliases: Flow, ExpressionWrapper, Expression

typeParameter​

JavaScript
t.typeParameter(bound, default, variance);

See also t.isTypeParameter(node, opts) and t.assertTypeParameter(node, opts).

AST Node TypeParameter shape:

  • bound: TypeAnnotation (default: null)
  • default: FlowType (default: null)
  • variance: Variance (default: null)
  • name: string (required)

Aliases: Flow

typeParameterDeclaration​

JavaScript
t.typeParameterDeclaration(params);

See also t.isTypeParameterDeclaration(node, opts) and t.assertTypeParameterDeclaration(node, opts).

AST Node TypeParameterDeclaration shape:

  • params: Array<TypeParameter> (required)

Aliases: Flow

typeParameterInstantiation​

JavaScript
t.typeParameterInstantiation(params);

See also t.isTypeParameterInstantiation(node, opts) and t.assertTypeParameterInstantiation(node, opts).

AST Node TypeParameterInstantiation shape:

  • params: Array<FlowType> (required)

Aliases: Flow

typeofTypeAnnotation​

JavaScript
t.typeofTypeAnnotation(argument);

See also t.isTypeofTypeAnnotation(node, opts) and t.assertTypeofTypeAnnotation(node, opts).

AST Node TypeofTypeAnnotation shape:

  • argument: FlowType (required)

Aliases: Flow, FlowType

unaryExpression​

JavaScript
t.unaryExpression(operator, argument, prefix);

See also t.isUnaryExpression(node, opts) and t.assertUnaryExpression(node, opts).

AST Node UnaryExpression shape:

  • operator: "void" | "throw" | "delete" | "!" | "+" | "-" | "~" | "typeof" (required)
  • argument: Expression (required)
  • prefix: boolean (default: true)

Aliases: Standardized, UnaryLike, Expression

unionTypeAnnotation​

JavaScript
t.unionTypeAnnotation(types);

See also t.isUnionTypeAnnotation(node, opts) and t.assertUnionTypeAnnotation(node, opts).

AST Node UnionTypeAnnotation shape:

  • types: Array<FlowType> (required)

Aliases: Flow, FlowType

updateExpression​

JavaScript
t.updateExpression(operator, argument, prefix);

See also t.isUpdateExpression(node, opts) and t.assertUpdateExpression(node, opts).

AST Node UpdateExpression shape:

  • operator: "++" | "--" (required)
  • argument: Expression (required)
  • prefix: boolean (default: false)

Aliases: Standardized, Expression

v8IntrinsicIdentifier​

JavaScript
t.v8IntrinsicIdentifier(name);

See also t.isV8IntrinsicIdentifier(node, opts) and t.assertV8IntrinsicIdentifier(node, opts).

AST Node V8IntrinsicIdentifier shape:

  • name: string (required)

Aliases: Miscellaneous

variableDeclaration​

JavaScript
t.variableDeclaration(kind, declarations);
History
VersionChanges
v7.20.0kind can be "using".

See also t.isVariableDeclaration(node, opts) and t.assertVariableDeclaration(node, opts).

AST Node VariableDeclaration shape:

  • kind: "var" | "let" | "const" | "using" | "await using" (required)
  • declarations: Array<VariableDeclarator> (required)
  • declare: boolean (default: null, excluded from builder function)

Aliases: Standardized, Statement, Declaration

variableDeclarator​

JavaScript
t.variableDeclarator(id, init);

See also t.isVariableDeclarator(node, opts) and t.assertVariableDeclarator(node, opts).

AST Node VariableDeclarator shape:

  • id: LVal (required)
  • init: Expression (default: null)
  • definite: boolean (default: null, excluded from builder function)

Aliases: Standardized

variance​

JavaScript
t.variance(kind);

See also t.isVariance(node, opts) and t.assertVariance(node, opts).

AST Node Variance shape:

  • kind: "minus" | "plus" (required)

Aliases: Flow

voidTypeAnnotation​

JavaScript
t.voidTypeAnnotation();

See also t.isVoidTypeAnnotation(node, opts) and t.assertVoidTypeAnnotation(node, opts).

Aliases: Flow, FlowType, FlowBaseAnnotation

whileStatement​

JavaScript
t.whileStatement(test, body);

See also t.isWhileStatement(node, opts) and t.assertWhileStatement(node, opts).

AST Node WhileStatement shape:

  • test: Expression (required)
  • body: Statement (required)

Aliases: Standardized, Statement, BlockParent, Loop, While, Scopable

withStatement​

JavaScript
t.withStatement(object, body);

See also t.isWithStatement(node, opts) and t.assertWithStatement(node, opts).

AST Node WithStatement shape:

  • object: Expression (required)
  • body: Statement (required)

Aliases: Standardized, Statement

yieldExpression​

JavaScript
t.yieldExpression(argument, delegate);

See also t.isYieldExpression(node, opts) and t.assertYieldExpression(node, opts).

AST Node YieldExpression shape:

  • argument: Expression (default: null)
  • delegate: boolean (default: false)

Aliases: Standardized, Expression, Terminatorless

Aliases​

Accessor​

Deprecated. Will be removed in Babel 8.

JavaScript
t.isAccessor(node);

Covered nodes:

Binary​

A cover of BinaryExpression and LogicalExpression, which share the same AST shape.

JavaScript
t.isBinary(node);

Covered nodes:

Block​

Deprecated. Will be removed in Babel 8.

JavaScript
t.isBlock(node);

Covered nodes:

BlockParent​

A cover of AST nodes that start an execution context with new LexicalEnvironment. In other words, they define the scope of let and const declarations.

JavaScript
t.isBlockParent(node);

Covered nodes:

Class​

A cover of ClassExpression and ClassDeclaration, which share the same AST shape.

JavaScript
t.isClass(node);

Covered nodes:

CompletionStatement​

A statement that indicates the completion records. In other words, they define the control flow of the program, such as when should a loop break or an action throws critical errors.

JavaScript
t.isCompletionStatement(node);

Covered nodes:

Conditional​

A cover of ConditionalExpression and IfStatement, which share the same AST shape.

JavaScript
t.isConditional(node);

Covered nodes:

Declaration​

A cover of any Declarations.

JavaScript
t.isDeclaration(node);

Covered nodes:

EnumBody​

A cover of Flow enum bodies.

JavaScript
t.isEnumBody(node);

Covered nodes:

EnumMember​

A cover of Flow enum members.

JavaScript
t.isEnumMember(node);

Covered nodes:

ExportDeclaration​

A cover of any ExportDeclarations.

JavaScript
t.isExportDeclaration(node);

Covered nodes:

Expression​

A cover of any Expressions.

JavaScript
t.isExpression(node);

Covered nodes:

ExpressionWrapper​

A wrapper of expression that does not have runtime semantics.

JavaScript
t.isExpressionWrapper(node);

Covered nodes:

Flow​

A cover of AST nodes defined for Flow.

JavaScript
t.isFlow(node);

Covered nodes:

FlowBaseAnnotation​

A cover of primary Flow type annotations.

JavaScript
t.isFlowBaseAnnotation(node);

Covered nodes:

FlowDeclaration​

A cover of Flow declarations.

JavaScript
t.isFlowDeclaration(node);

Covered nodes:

FlowPredicate​

A cover of Flow predicates.

JavaScript
t.isFlowPredicate(node);

Covered nodes:

FlowType​

A cover of Flow type annotations.

JavaScript
t.isFlowType(node);

Covered nodes:

For​

A cover of ForStatements and ForXStatements.

JavaScript
t.isFor(node);

Covered nodes:

ForXStatement​

A cover of ForInStatements and ForOfStatements.

JavaScript
t.isForXStatement(node);

Covered nodes:

Function​

A cover of functions and methods, the must have body and params. Note: Function is different to FunctionParent. For example, a StaticBlock is a FunctionParent but not Function.

JavaScript
t.isFunction(node);

Covered nodes:

FunctionParent​

A cover of AST nodes that start an execution context with new VariableEnvironment. In other words, they define the scope of var declarations. FunctionParent did not include Program since Babel 7.

JavaScript
t.isFunctionParent(node);

Covered nodes:

Immutable​

A cover of immutable objects and JSX elements. An object is immutable if no other properties can be defined once created.

JavaScript
t.isImmutable(node);

Covered nodes:

ImportOrExportDeclaration​

History
VersionChanges
v7.21.0Introduced

A cover of ImportDeclaration and ExportDeclaration.

JavaScript
t.isImportOrExportDeclaration(node);

Covered nodes:

JSX​

A cover of AST nodes defined for JSX.

JavaScript
t.isJSX(node);

Covered nodes:

LVal​

A cover of left hand side expressions used in the left of assignment expressions and ForXStatements.

JavaScript
t.isLVal(node);

Covered nodes:

Literal​

A cover of Literals, Regular Expression Literals and Template Literals.

JavaScript
t.isLiteral(node);

Covered nodes:

Loop​

A cover of loop statements.

JavaScript
t.isLoop(node);

Covered nodes:

Method​

A cover of object methods and class methods.

JavaScript
t.isMethod(node);

Covered nodes:

Miscellaneous​

A cover of non-standard AST types that are sometimes useful for development.

JavaScript
t.isMiscellaneous(node);

Covered nodes:

ModuleDeclaration​

History
VersionChanges
v7.21.0Deprecated
caution

Deprecated, use ImportOrExportDeclaration instead. Check out PR #15266 for migration notes.

JavaScript
t.isModuleDeclaration(node);

Covered nodes:

ModuleSpecifier​

A cover of import and export specifiers. Note: It is not the ModuleSpecifier defined in the spec.

JavaScript
t.isModuleSpecifier(node);

Covered nodes:

ObjectMember​

A cover of members in an object literal.

JavaScript
t.isObjectMember(node);

Covered nodes:

Pattern​

A cover of BindingPattern except Identifiers.

JavaScript
t.isPattern(node);

Covered nodes:

PatternLike​

A cover of BindingPatterns.

JavaScript
t.isPatternLike(node);

Covered nodes:

Private​

A cover of private class elements and private identifiers.

JavaScript
t.isPrivate(node);

Covered nodes:

Property​

A cover of object properties and class properties.

JavaScript
t.isProperty(node);

Covered nodes:

Pureish​

A cover of AST nodes which do not have side-effects. In other words, there is no observable behaviour changes if they are evaluated more than once.

JavaScript
t.isPureish(node);

Covered nodes:

Scopable​

A cover of FunctionParent and BlockParent.

JavaScript
t.isScopable(node);

Covered nodes:

Standardized​

A cover of AST nodes which are part of an official ECMAScript specification.

JavaScript
t.isStandardized(node);

Covered nodes:

Statement​

A cover of any Statements.

JavaScript
t.isStatement(node);

Covered nodes:

TSBaseType​

A cover of primary TypeScript type annotations.

JavaScript
t.isTSBaseType(node);

Covered nodes:

TSEntityName​

A cover of ts entities.

JavaScript
t.isTSEntityName(node);

Covered nodes:

TSType​

A cover of TypeScript type annotations.

JavaScript
t.isTSType(node);

Covered nodes:

TSTypeElement​

A cover of TypeScript type declarations.

JavaScript
t.isTSTypeElement(node);

Covered nodes:

Terminatorless​

A cover of AST nodes whose semantic will change when a line terminator is inserted between the operator and the operand.

JavaScript
t.isTerminatorless(node);

Covered nodes:

TypeScript​

A cover of AST nodes defined for TypeScript.

JavaScript
t.isTypeScript(node);

Covered nodes:

UnaryLike​

A cover of UnaryExpression and SpreadElement.

JavaScript
t.isUnaryLike(node);

Covered nodes:

UserWhitespacable​

Deprecated. Will be removed in Babel 8.

JavaScript
t.isUserWhitespacable(node);

Covered nodes:

While​

A cover of DoWhileStatement and WhileStatement, which share the same AST shape.

JavaScript
t.isWhile(node);

Covered nodes: