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Map.prototype.clear() - JavaScript | MDN
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Map.prototype.clear()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The clear()
method of Map
instances removes all elements from this map.
Try it
const map = new Map();
map.set("bar", "baz");
map.set(1, "foo");
console.log(map.size);
// Expected output: 2
map.clear();
console.log(map.size);
// Expected output: 0
Syntax
js
clear()
Parameters
None.
Return value
None (undefined
).
Examples
>Using clear()
js
const myMap = new Map();
myMap.set("bar", "baz");
myMap.set(1, "foo");
console.log(myMap.size); // 2
console.log(myMap.has("bar")); // true
myMap.clear();
console.log(myMap.size); // 0
console.log(myMap.has("bar")); // false
Specifications
Specification |
---|
ECMAScript® 2026 Language Specification> # sec-map.prototype.clear> |
Browser compatibility
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