The add()
method appends a new object to the end of a WeakSet
object.
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Syntax
ws.add(value);
Parameters
- value
- Required. The object to add to the
WeakSet
collection.
Return value
The WeakSet
object.
Examples
Using add
var ws = new WeakSet(); ws.add(window); // add the window object to the WeakSet ws.has(window); // true // Weakset only takes objects as arguments ws.add(1); // results in "TypeError: Invalid value used in weak set" in Chrome // and "TypeError: 1 is not a non-null object" in Firefox
Specifications
Specification |
---|
ECMAScript (ECMA-262) The definition of 'WeakSet.prototype.add' 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 | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
add | 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