The has()
method returns a boolean indicating whether an object exists in a WeakSet
or not.
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Syntax
ws.has(value);
Parameters
- value
- Required. The object to test for presence in the
WeakSet
.
Return value
- Boolean
- Returns
true
if an element with the specified value exists in theWeakSet
object; otherwisefalse
.
Examples
Using the has
method
var ws = new WeakSet(); var obj = {}; ws.add(window); mySet.has(window); // returns true mySet.has(obj); // returns false
Specifications
Specification |
---|
ECMAScript (ECMA-262) The definition of 'WeakSet.prototype.has' in that specification. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
has | Chrome Full support 36 | Edge Full support 12 | Firefox Full support 34 | IE No support No | Opera Full support 23 | Safari Full support 9 | WebView Android Full support 37 | Chrome Android Full support 36 | Firefox Android Full support 34 | Opera Android Full support 24 | Safari iOS Full support 9 | Samsung Internet Android Full support 3.0 | nodejs Full support 0.12 |
Legend
- Full support
- Full support
- No support
- No support