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The delete() method removes the specified element from a WeakSet object.




Required. The object remove from the WeakSet 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 or if the key is not an object.


Using the delete method

var ws = new WeakSet();
var obj = {};


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.


Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'WeakSet.prototype.delete' in that specification.
Standard Initial definition.
ECMAScript 2017 Draft (ECMA-262)
The definition of 'WeakSet.prototype.delete' in that specification.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 36 34 (34) No support 23 No support
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support 34.0 (34) No support No support No support

See also

Document Tags and Contributors

 Contributors to this page: eduardoboucas, chrisdavidmills, fscholz, realityking, teoli
 Last updated by: eduardoboucas,