WeakSet.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 September 2015.

The delete() method of WeakSet instances removes the specified value from this set, if it is in the set.

Try it

const weakset = new WeakSet();
const object = {};

weakset.add(object);

console.log(weakset.has(object));
// Expected output: true

weakset.delete(object);

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

Syntax

js
weakSetInstance.delete(value)

Parameters

value

The value to remove from the WeakSet object. Objects are compared by reference, not by value.

Return value

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

Examples

Using delete()

js
const ws = new WeakSet();
const obj = {};

ws.add(window);

ws.delete(obj); // Returns false. No obj found to be deleted.
ws.delete(window); // Returns true. Successfully removed.

ws.has(window); // Returns false. The window is no longer present in the WeakSet.

Specifications

Specification
ECMAScript® 2027 Language Specification
# sec-weakset.prototype.delete

Browser compatibility

desktop mobile server
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Bun
Deno
Node.js
delete
Chrome – Full support
Chrome 36 (Release date: 2014-07-16)
footnote Full support
Edge – Full support
Edge 12 (Release date: 2015-07-29)
footnote Full support
Firefox – Full support
Firefox 34 (Release date: 2014-12-01)
footnote Full support
Opera – Full support
Opera 23 (Release date: 2014-07-22)
footnote Full support
Safari – Full support
Safari 9 (Release date: 2015-09-30)
footnote Full support
Chrome Android – Full support
Chrome Android 36 (Release date: 2014-07-16)
footnote Full support
Firefox for Android – Full support
Firefox for Android 34 (Release date: 2014-12-01)
footnote Full support
Opera Android – Full support
Opera Android 24 (Release date: 2014-09-10)
footnote Full support
Safari on iOS – Full support
Safari on iOS 9 (Release date: 2015-09-16)
footnote Full support
Samsung Internet – Full support
Samsung Internet 3 (Release date: 2015-04-10)
footnote Full support
WebView Android – Full support
WebView Android 37 (Release date: 2014-09-03)
footnote Full support
WebView on iOS – Full support
WebView on iOS 9 (Release date: 2015-09-16)
footnote Full support
Bun – Full support
Bun 1 (Release date: 2023-09-08)
footnote Full support
Deno – Full support
Deno 1 (Release date: 2020-05-13)
footnote Full support
Node.js – Full support
Node.js 0.12 (Release date: 2015-02-06)
footnote Full support

Legend

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Full support
Full support

See also