WeakMap.prototype.delete()

The delete() method of WeakMap instances removes the entry specified by the key from this WeakMap.

Try it

const weakmap = new WeakMap();
const object = {};

weakmap.set(object, 42);

console.log(weakmap.delete(object));
// Expected output: true

console.log(weakmap.has(object));
// Expected output: false

Syntax

js
weakMapInstance.delete(key)

Parameters

key

The key of the entry to remove from the WeakMap object. Object keys are compared by reference, not by value.

Return value

true if an entry 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

undefined

Using delete()

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

See also