WeakMap.prototype.delete()
BaselineWidely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
Thedelete() method ofWeakMap instances removes the specified element from thisWeakMap.
Try it
const weakmap1 = new WeakMap();const object1 = {};weakmap1.set(object1, 42);console.log(weakmap1.delete(object1));// Expected output: trueconsole.log(weakmap1.has(object1));// Expected output: falseSyntax
js
weakMapInstance.delete(key)Parameters
keyThe key of the element to remove from the
WeakMapobject.
Return value
true if an element in theWeakMap object has been removed successfully.false if the key is not found in theWeakMap. Always returnsfalse ifkey is not an object or anon-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
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-weakmap.prototype.delete |