JavaScript Reference

JavaScript Reference the facts about the language

JavaScript Reference

Table of Content

Built-in objects

Array

ArrayBuffer

AsyncFunction

Atomics

Boolean

DataView

Date

Error

EvalError

Float32Array

Float64Array

Function

Generator

GeneratorFunction

Infinity

Int16Array

Int32Array

Int8Array

InternalError

Intl

Intl.Collator

Intl.DateTimeFormat

Intl.NumberFormat

JSON

Map

Math

NaN

Number

Object

Promise

Proxy

RangeError

ReferenceError

Reflect

RegExp

SIMD

SIMD.Bool16x8

SIMD.Bool32x4

SIMD.Bool64x2

SIMD.Bool8x16

SIMD.Float32x4

SIMD.Float64x2

SIMD.Int16x8

SIMD.Int32x4

SIMD.Int8x16

SIMD.Uint16x8

SIMD.Uint32x4

SIMD.Uint8x16

Set

SharedArrayBuffer

String

Symbol

SyntaxError

TypeError

TypedArray

URIError

Uint16Array

Uint32Array

Uint8Array

Uint8ClampedArray

WeakMap

WeakSet

WebAssembly

decodeURI()

decodeURIComponent()

encodeURI()

encodeURIComponent()

escape()

eval()

isFinite()

isNaN()

null

parseFloat()

parseInt()

undefined

unescape()

uneval()

Expressions & operators

Arithmetic operators

Array comprehensions

Assignment operators

Bitwise operators

Comma operator

Comparison operators

Conditional (ternary)

Destructuring

Expression closures

Generator comprehensions

Grouping operator

Legacy generator function expression

Logical Operators

Object initializer

Operator precedence

Property accessors

Spread syntax

async function expression

await

class expression

delete operator

function expression

function* expression

in operator

instanceof

new operator

new.target

super

this

typeof

void operator

yield

yield*

Statements & declarations

Legacy generator function

async function

block

break

class

const

continue

debugger

default

do...while

empty

export

for

for each...in

for...in

for...of

function declaration

function*

if...else

import

label

let

return

switch

throw

try...catch

var

while

with

Functions

Arguments object

Arrow functions

Default parameters

Method definitions

Rest parameters

getter

setter

Classes

constructor

extends

static

Errors

Error: Permission denied to access property "x"

InternalError: too much recursion

RangeError: argument is not a valid code point

RangeError: invalid array length

RangeError: invalid date

RangeError: precision is out of range

RangeError: radix must be an integer

RangeError: repeat count must be less than infinity

RangeError: repeat count must be non-negative

ReferenceError: "x" is not defined

ReferenceError: assignment to undeclared variable "x"

ReferenceError: can't access lexical declaration`X' before initialization

ReferenceError: deprecated caller or arguments usage

ReferenceError: invalid assignment left-hand side

ReferenceError: reference to undefined property "x"

URIError: malformed URI sequence

Warning: -file- is being assigned a //# sourceMappingURL, but already has one

Warning: 08/09 is not a legal ECMA-262 octal constant

Warning: Date.prototype.toLocaleFormat is deprecated

Warning: JavaScript 1.6's for-each-in loops are deprecated

Warning: String.x is deprecated; use String.prototype.x instead

Warning: expression closures are deprecated

Warning: unreachable code after return statement

X.prototype.y called on incompatible type

JavaScript technologies overview

Lexical grammar

JavaScript data structures

Enumerability and ownership of properties

Iteration protocols

Strict mode

Transitioning to strict mode

Template literals

Deprecated features

New in JavaScript

ECMAScript 2015 support in Mozilla

ECMAScript 5 support in Mozilla

ECMAScript Next support in Mozilla

Firefox JavaScript changelog

All pages index

Methods index

Properties index