The Symbol.keyFor(sym)
method retrieves a shared symbol key from the global symbol registry for the given symbol.
Syntax
Symbol.keyFor(sym);
Parameters
- sym
- Symbol, required. The symbol to find a key for.
Return value
A string representing the key for the given symbol if one is found on the global registry; otherwise, undefined
.
Examples
var globalSym = Symbol.for('foo'); // create a new global symbol Symbol.keyFor(globalSym); // "foo" var localSym = Symbol(); Symbol.keyFor(localSym); // undefined // well-known symbols are not symbols registered // in the global symbol registry Symbol.keyFor(Symbol.iterator) // undefined
Specifications
Specification | Status | Comment |
---|---|---|
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Symbol.keyFor' in that specification. |
Standard | Initial definition. |
ECMAScript Latest Draft (ECMA-262) The definition of 'Symbol.keyFor' in that specification. |
Living Standard |
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.
Feature | Chrome | Edge | Firefox | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|---|
Basic support | 40 | Yes | 36 | No | Yes | 9 |
Feature | Android webview | Chrome for Android | Edge mobile | Firefox for Android | IE mobile | Opera Android | iOS Safari |
---|---|---|---|---|---|---|---|
Basic support | Yes | Yes | Yes | 36 | No | Yes | 9 |