WeakMap.prototype.delete()
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.
Thedelete() method ofWeakMap instances removes the entry specified by the key from thisWeakMap.
Try it
const weakmap = new WeakMap();const object = {};weakmap.set(object, 42);console.log(weakmap.delete(object));// Expected output: trueconsole.log(weakmap.has(object));// Expected output: falseSyntax
js
weakMapInstance.delete(key)Parameters
Return value
true if an entry 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 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
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-weakmap.prototype.delete |