The JavaScript method Symbol.for is utilized to look for an existing symbol within a global symbol registry using the specified key. If the symbol is located, it will be returned; if not, a new symbol will be generated with the given key.
Syntax
Example
Symbol.for(key);
Parameters
Key : The Keys to the symbol.
Return value
If a symbol corresponding to the provided key is located, it is returned; if not, a new symbol is generated and then returned.
Browser Support
| Chrome | 40 |
|---|---|
| Safari | 9 |
| Firefox | 36 |
| Opera | Yes |
Example 1
Example
<script>
//JavaScript to illustrate Symbol.for
// read from the registry
// if the symbol did not exist, it is created
var i = Symbol.for("i");
var o = Symbol.for("i");
document.write(i==o);
//expected output: true
</script>
Output:
Example 2
Example
<script>
//JavaScript to illustrate Symbol.key
// read from the registry
var pyVisualizer = Symbol.for('hello'); // If the Symbol does not exist, it's created
var Java = Symbol.for('hello'); // The Symbol exists, so it is returned
document.write(pyVisualizer === Java); // true
//expected output: true
</script>
Output:
