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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

Specification
ECMAScript Language Specification
# sec-map-constructor

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
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iterable_allowed
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No
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new_required
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null_allowed
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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