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Map() constructor

The Map() creates Map objects.

Syntax

new Map()
new Map(iterable)

Note: Map() can only be constructed with new. Attempting to call it without new throws a TypeError.

Parameters

iterable Optional

An Array or other iterable object whose elements are key-value pairs. (For example, arrays with two elements, such as [[ 1, 'one' ],[ 2, 'two' ]].) Each key-value pair is added to the new Map.

Examples

Creating a new Map

const myMap = new Map([
  [1, 'one'],
  [2, 'two'],
  [3, 'three'],
]);

Specifications

Browser compatibility

Desktop Mobile Server
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet Deno Node.js
Map
38
12
13
11
25
8
38
38
14
25
8
3.0
1.0
0.12.0
0.10.0
iterable_allowed
38
12
13
No
25
9
38
38
14
25
9
3.0
1.0
0.12.0
new_required
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12
42
11
25
9
38
38
42
25
9
3.0
1.0
0.12.0
null_allowed
38
12
37
11
25
9
38
38
37
25
9
3.0
1.0
0.12.0
0.10.0

See also

© 2005–2022 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Map/Map