The initial value of the @@iterator
property is the same function object as the initial value of the entries
method.
The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.
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
Specification |
---|
ECMAScript (ECMA-262) The definition of 'Map.prototype[@@iterator]()' in that specification. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
@@iterator | Chrome Full support 43 | Edge Full support 12 | Firefox
Full support
36
| IE No support No | Opera Full support 30 | Safari Full support 10 | WebView Android Full support 43 | Chrome Android Full support 43 | Firefox Android
Full support
36
| Opera Android Full support 30 | Safari iOS Full support 10 | Samsung Internet Android Full support 4.0 | nodejs Full support 0.12 |
Legend
- Full support
- Full support
- No support
- No support
- See implementation notes.
- See implementation notes.
- Uses a non-standard name.
- Uses a non-standard name.