SyntaxKind

The SyntaxKind enum identifies the type of each node in the TypeScript Abstract Syntax Tree (AST). Every node has a kind property that determines its type and structure.

export const enum SyntaxKind {
  Unknown,
  EndOfFileToken,
  // ... hundreds of kinds
}

Trivia and Tokens

Trivia (Comments and Whitespace)

Kind	Value	Description
`Unknown`	0	Unknown token
`EndOfFileToken`	1	End of file marker
`SingleLineCommentTrivia`	2	`// comment`
`MultiLineCommentTrivia`	3	`/* comment */`
`NewLineTrivia`	4	Line break
`WhitespaceTrivia`	5	Spaces and tabs
`ShebangTrivia`	6	`#!/usr/bin/env node`
`ConflictMarkerTrivia`	7	Git conflict markers

Literals

Primary Literals

Kind	Description	Example
`NumericLiteral`	Number literal	`42`, `3.14`
`BigIntLiteral`	BigInt literal	`100n`
`StringLiteral`	String literal	`"hello"`, `'world'`
`RegularExpressionLiteral`	Regex literal	`/pattern/g`
`NoSubstitutionTemplateLiteral`	Template without expressions	`text`

Template Literals

Kind	Description
`TemplateHead`	`start ${
`TemplateMiddle`	`} middle ${`
`TemplateTail`	} end`

Punctuation

Braces and Brackets

Kind	Symbol
`OpenBraceToken`	`{`
`CloseBraceToken`	`}`
`OpenParenToken`	`(`
`CloseParenToken`	`)`
`OpenBracketToken`	`[`
`CloseBracketToken`	`]`

Operators

Kind	Symbol	Description
`PlusToken`	`+`	Addition
`MinusToken`	`-`	Subtraction
`AsteriskToken`	`*`	Multiplication
`AsteriskAsteriskToken`	`**`	Exponentiation
`SlashToken`	`/`	Division
`PercentToken`	`%`	Modulo
`PlusPlusToken`	`++`	Increment
`MinusMinusToken`	`--`	Decrement
`LessThanToken`	`<`	Less than
`GreaterThanToken`	`>`	Greater than
`LessThanEqualsToken`	`<=`	Less than or equal
`GreaterThanEqualsToken`	`>=`	Greater than or equal
`EqualsEqualsToken`	`==`	Equality
`ExclamationEqualsToken`	`!=`	Inequality
`EqualsEqualsEqualsToken`	`===`	Strict equality
`ExclamationEqualsEqualsToken`	`!==`	Strict inequality
`EqualsGreaterThanToken`	`=>`	Arrow function
`AmpersandToken`	`&`	Bitwise AND
`BarToken`	`	`	Bitwise OR
`CaretToken`	`^`	Bitwise XOR
`TildeToken`	`~`	Bitwise NOT
`AmpersandAmpersandToken`	`&&`	Logical AND
`BarBarToken`	`		`	Logical OR
`QuestionQuestionToken`	`??`	Nullish coalescing

Other Punctuation

Kind	Symbol
`DotToken`	`.`
`DotDotDotToken`	`...`
`SemicolonToken`	`;`
`CommaToken`	`,`
`QuestionToken`	`?`
`ColonToken`	`:`
`AtToken`	`@`
`QuestionDotToken`	`?.`
`ExclamationToken`	`!`

Assignment Operators

Kind	Symbol
`EqualsToken`	`=`
`PlusEqualsToken`	`+=`
`MinusEqualsToken`	`-=`
`AsteriskEqualsToken`	`*=`
`AsteriskAsteriskEqualsToken`	`**=`
`SlashEqualsToken`	`/=`
`PercentEqualsToken`	`%=`
`AmpersandEqualsToken`	`&=`
`BarEqualsToken`	`	=`
`CaretEqualsToken`	`^=`
`AmpersandAmpersandEqualsToken`	`&&=`
`BarBarEqualsToken`	`		=`
`QuestionQuestionEqualsToken`	`??=`

Keywords

Reserved Words

Keyword	SyntaxKind
`break`	`BreakKeyword`
`case`	`CaseKeyword`
`catch`	`CatchKeyword`
`class`	`ClassKeyword`
`const`	`ConstKeyword`
`continue`	`ContinueKeyword`
`debugger`	`DebuggerKeyword`
`default`	`DefaultKeyword`
`delete`	`DeleteKeyword`
`do`	`DoKeyword`
`else`	`ElseKeyword`
`enum`	`EnumKeyword`
`export`	`ExportKeyword`
`extends`	`ExtendsKeyword`
`false`	`FalseKeyword`
`finally`	`FinallyKeyword`
`for`	`ForKeyword`
`function`	`FunctionKeyword`
`if`	`IfKeyword`
`import`	`ImportKeyword`
`in`	`InKeyword`
`instanceof`	`InstanceOfKeyword`
`new`	`NewKeyword`
`null`	`NullKeyword`
`return`	`ReturnKeyword`
`super`	`SuperKeyword`
`switch`	`SwitchKeyword`
`this`	`ThisKeyword`
`throw`	`ThrowKeyword`
`true`	`TrueKeyword`
`try`	`TryKeyword`
`typeof`	`TypeOfKeyword`
`var`	`VarKeyword`
`void`	`VoidKeyword`
`while`	`WhileKeyword`
`with`	`WithKeyword`

Strict Mode Reserved Words

Keyword	SyntaxKind
`implements`	`ImplementsKeyword`
`interface`	`InterfaceKeyword`
`let`	`LetKeyword`
`package`	`PackageKeyword`
`private`	`PrivateKeyword`
`protected`	`ProtectedKeyword`
`public`	`PublicKeyword`
`static`	`StaticKeyword`
`yield`	`YieldKeyword`

Contextual Keywords

Keyword	SyntaxKind	Usage
`abstract`	`AbstractKeyword`	Abstract classes/methods
`accessor`	`AccessorKeyword`	Auto-accessor fields
`any`	`AnyKeyword`	Any type
`as`	`AsKeyword`	Type assertions
`asserts`	`AssertsKeyword`	Assertion signatures
`assert`	`AssertKeyword`	Import assertions
`async`	`AsyncKeyword`	Async functions
`await`	`AwaitKeyword`	Await expressions
`boolean`	`BooleanKeyword`	Boolean type
`constructor`	`ConstructorKeyword`	Constructors
`declare`	`DeclareKeyword`	Ambient declarations
`get`	`GetKeyword`	Getter methods
`infer`	`InferKeyword`	Type inference
`intrinsic`	`IntrinsicKeyword`	Intrinsic types
`is`	`IsKeyword`	Type predicates
`keyof`	`KeyOfKeyword`	Keyof operator
`module`	`ModuleKeyword`	Module declarations
`namespace`	`NamespaceKeyword`	Namespaces
`never`	`NeverKeyword`	Never type
`number`	`NumberKeyword`	Number type
`object`	`ObjectKeyword`	Object type
`out`	`OutKeyword`	Covariance annotation
`override`	`OverrideKeyword`	Override modifier
`readonly`	`ReadonlyKeyword`	Readonly modifier
`require`	`RequireKeyword`	Require calls
`satisfies`	`SatisfiesKeyword`	Satisfies operator
`set`	`SetKeyword`	Setter methods
`string`	`StringKeyword`	String type
`symbol`	`SymbolKeyword`	Symbol type
`type`	`TypeKeyword`	Type aliases
`undefined`	`UndefinedKeyword`	Undefined type
`unique`	`UniqueKeyword`	Unique symbols
`unknown`	`UnknownKeyword`	Unknown type
`using`	`UsingKeyword`	Using declarations
`from`	`FromKeyword`	Import from
`global`	`GlobalKeyword`	Global augmentation
`bigint`	`BigIntKeyword`	BigInt type
`of`	`OfKeyword`	For-of loops
`defer`	`DeferKeyword`	Deferred evaluation

Parse Tree Nodes

Names

QualifiedName - A.B.C
ComputedPropertyName - [expr]

Type Members

PropertySignature
PropertyDeclaration
MethodSignature
MethodDeclaration
Constructor
GetAccessor
SetAccessor
CallSignature
ConstructSignature
IndexSignature

Types

TypePredicate
TypeReference
FunctionType
ConstructorType
TypeQuery
TypeLiteral
ArrayType
TupleType
UnionType
IntersectionType
ConditionalType
InferType
MappedType
TemplateLiteralType
ImportType

Expressions

ArrayLiteralExpression
ObjectLiteralExpression
PropertyAccessExpression
ElementAccessExpression
CallExpression
NewExpression
TaggedTemplateExpression
TypeAssertionExpression
ParenthesizedExpression
FunctionExpression
ArrowFunction
DeleteExpression
TypeOfExpression
VoidExpression
AwaitExpression
PrefixUnaryExpression
PostfixUnaryExpression
BinaryExpression
ConditionalExpression
YieldExpression
SpreadElement
ClassExpression
AsExpression
NonNullExpression
SatisfiesExpression

Statements

Block
VariableStatement
ExpressionStatement
IfStatement
DoStatement
WhileStatement
ForStatement
ForInStatement
ForOfStatement
ContinueStatement
BreakStatement
ReturnStatement
WithStatement
SwitchStatement
LabeledStatement
ThrowStatement
TryStatement
DebuggerStatement

Declarations

VariableDeclaration
FunctionDeclaration
ClassDeclaration
InterfaceDeclaration
TypeAliasDeclaration
EnumDeclaration
ModuleDeclaration
ImportDeclaration
ExportDeclaration
ImportEqualsDeclaration
ExportAssignment

JSX

JsxElement
JsxSelfClosingElement
JsxOpeningElement
JsxClosingElement
JsxFragment
JsxAttribute
JsxSpreadAttribute
JsxExpression

Other

SourceFile - Root node
Bundle - Multiple source files
SyntaxList - List of nodes

Helper Markers

The enum includes helper values for ranges:

FirstAssignment = EqualsToken,
LastAssignment = CaretEqualsToken,
FirstReservedWord = BreakKeyword,
LastReservedWord = WithKeyword,
FirstKeyword = BreakKeyword,
LastKeyword = DeferKeyword,
FirstPunctuation = OpenBraceToken,
LastPunctuation = CaretEqualsToken,

Usage

Checking Node Kind

import ts from 'typescript';

if (node.kind === ts.SyntaxKind.FunctionDeclaration) {
  console.log('Found a function declaration');
}

// Or use type guards
if (ts.isFunctionDeclaration(node)) {
  console.log('Found a function declaration');
}

Getting Kind Name

const kindName = ts.SyntaxKind[node.kind];
console.log(`Node kind: ${kindName}`);

Compiler API

Language Service API

Types and Interfaces

Trivia and Tokens

Trivia (Comments and Whitespace)

Literals

Primary Literals

Template Literals

Punctuation

Braces and Brackets

Operators

Other Punctuation

Assignment Operators

Keywords

Reserved Words

Strict Mode Reserved Words

Contextual Keywords

Parse Tree Nodes

Names

Type Members

Types

Expressions

Statements

Declarations

JSX

Other

Helper Markers

Usage

Checking Node Kind

Getting Kind Name

See Also

Build docs developers (and LLMs) love

Compiler API

Language Service API

Types and Interfaces

​Trivia and Tokens

​Trivia (Comments and Whitespace)

​Literals

​Primary Literals

​Template Literals

​Punctuation

​Braces and Brackets

​Operators

​Other Punctuation

​Assignment Operators

​Keywords

​Reserved Words

​Strict Mode Reserved Words

​Contextual Keywords

​Parse Tree Nodes

​Names

​Type Members

​Types

​Expressions

​Statements

​Declarations

​JSX

​Other

​Helper Markers

​Usage

​Checking Node Kind

​Getting Kind Name

​See Also

Build docs developers (and LLMs) love

Trivia and Tokens

Trivia (Comments and Whitespace)

Literals

Primary Literals

Template Literals

Punctuation

Braces and Brackets

Operators

Other Punctuation

Assignment Operators

Keywords

Reserved Words

Strict Mode Reserved Words

Contextual Keywords

Parse Tree Nodes

Names

Type Members

Types

Expressions

Statements

Declarations

JSX

Other

Helper Markers

Usage

Checking Node Kind

Getting Kind Name

See Also