WeakMap.prototype.delete()

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

Syntax

wm.delete(key);

Parameters

key
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
ECMAScript (ECMA-262)
The definition of 'WeakMap.prototype.delete' in that specification.

Browser compatibility

DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
deleteChrome Full support 36Edge Full support 12Firefox Full support 6
Notes
Full support 6
Notes
Notes Prior to Firefox 38, this method threw a TypeError when the key parameter was not an object. This has been fixed in version 38 and later to return false as per the ES2015 standard.
IE Full support 11Opera Full support 23Safari Full support 8WebView Android Full support 37Chrome Android Full support 36Firefox Android Full support 6
Notes
Full support 6
Notes
Notes Prior to Firefox 38, this method threw a TypeError when the key parameter was not an object. This has been fixed in version 38 and later to return false as per the ES2015 standard.
Opera Android Full support 24Safari iOS Full support 8Samsung Internet Android Full support 3.0nodejs Full support 0.12
Full support 0.12
Full support 0.10
Disabled
Disabled From version 0.10: this feature is behind the --harmony runtime flag.

Legend

Full support
Full support
See implementation notes.
See implementation notes.
User must explicitly enable this feature.
User must explicitly enable this feature.

See also