The delete()
method removes the specified element from a WeakMap
object.
Syntax
wm.delete(key);
Parameters
- key
- Required. The key of the element to remove from the
WeakMap
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.
Examples
Using the delete
method
var 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 | Status | Comment |
---|---|---|
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'WeakMap.prototype.delete' in that specification. |
Standard | Initial definition. |
ECMAScript 2017 Draft (ECMA-262) The definition of 'WeakMap.prototype.delete' in that specification. |
Draft |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|
Basic support | 36 | 6.0 (6.0) | 11 | 23 | 7.1 |
Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|
Basic support | No support | 6.0 (6.0) | No support | No support | 8 |
Firefox-specific notes
- Prior to SpiderMonkey 38 (Firefox 38 / Thunderbird 38 / SeaMonkey 2.35), this method threw a
TypeError
when thekey
parameter was not an object. This has been fixed in version 38 and later to returnfalse
as per latest ES6 standard (bug 1127827).