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WeakMap.prototype.delete()

The delete() method of WeakMap instances removes the specified element from this WeakMap.

Try it

Syntax

js
weakMapInstance.delete(key)

Parameters

key

The key of the element to remove from the WeakMap object.

Return value

true if an element in the WeakMap object has been removed successfully. false if the key is not found in the WeakMap. Always returns false if key is not an object or a non-registered symbol.

Examples

Using the delete() method

js
const wm = new WeakMap();
wm.set(window, "foo");

wm.delete(window); // Returns true. Successfully removed.

wm.has(window); // Returns false. The window object is no longer in the WeakMap.

Specifications

Browser compatibility

Desktop Mobile Server
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android Deno Node.js
delete 36 12
6Before Firefox 38, this method threw a TypeError when the key parameter was not an object. This has been fixed in version 38 and later to return false as per the ES2015 standard.
23 8 36
6Before Firefox 38, this method threw a TypeError when the key parameter was not an object. This has been fixed in version 38 and later to return false as per the ES2015 standard.
24 8 3.0 37 1.0 0.12.0

See also

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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/WeakMap/delete