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[email protected]@iterator

The initial value of the @@iterator property is the same function object as the initial value of the entries method.

Syntax

myMap[Symbol.iterator]

Return value

The map iterator function, which is the entries() function by default.

Examples

Using [@@iterator]()

const myMap = new Map()
myMap.set('0', 'foo')
myMap.set(1, 'bar')
myMap.set({}, 'baz')

const mapIter = myMap[Symbol.iterator]()

console.log(mapIter.next().value) // ["0", "foo"]
console.log(mapIter.next().value) // [1, "bar"]
console.log(mapIter.next().value) // [Object, "baz"]

Using [@@iterator]() with for..of

const myMap = new Map()
myMap.set('0', 'foo')
myMap.set(1, 'bar')
myMap.set({}, 'baz')

for (const entry of myMap) {
  console.log(entry)
}
// ["0", "foo"]
// [1, "bar"]
// [{}, "baz"]

for (const [key, value] of myMap) {
  console.log(`${key}: ${value}`)
}
// 0: foo
// 1: bar
// [Object]: baz

Specifications

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
@@iterator 43 12 36
36
27 — 36
A placeholder property named @@iterator is used.
Uses the non-standard name: @@iterator
17 — 27
A placeholder property named iterator is used.
Uses the non-standard name: iterator
No 30 10
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
@@iterator 43 43 36
36
27 — 36
A placeholder property named @@iterator is used.
Uses the non-standard name: @@iterator
17 — 27
A placeholder property named iterator is used.
Uses the non-standard name: iterator
30 10 4.0
Server
Node.js
@@iterator 0.12

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://wiki.developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/@@iterator