Class Symbol
Symbol is a primitive data type that can serve as object properties. Symbol instance can be created explicitly or via a global registry, see for(String).
API Version:
Available from version 21.2.
| Constant | Description |
|---|---|
| hasInstance: Symbol | The symbol used by instanceof. |
| isConcatSpreadable: Symbol | The symbol used by Array.concat(Object...). |
| iterator: Symbol | The symbol used by for...of. |
| match: Symbol | The symbol used by String.match(RegExp). |
| replace: Symbol | The symbol used by String.replace(). |
| search: Symbol | The symbol used by String.search(RegExp). |
| species: Symbol | The symbol used to create derived objects. |
| split: Symbol | The symbol used by String.split(). |
| toPrimitive: Symbol | The symbol used to convert an object to a primitive value. |
| toStringTag: Symbol | The symbol used by Object.toString(). |
| unscopables: Symbol | The symbol used by with. |
| Constructor | Description |
|---|---|
| Symbol() | Creates a new symbol. |
| Symbol(String) | Creates a new symbol. |
| Method | Description |
|---|---|
| static for(String) | Obtains a symbol from the global registry. |
| static keyFor(Symbol) | Returns the key within the global symbol registry under which the given symbol is stored. |
assign, create, create, defineProperties, defineProperty, entries, freeze, fromEntries, getOwnPropertyDescriptor, getOwnPropertyNames, getOwnPropertySymbols, getPrototypeOf, hasOwnProperty, is, isExtensible, isFrozen, isPrototypeOf, isSealed, keys, preventExtensions, propertyIsEnumerable, seal, setPrototypeOf, toLocaleString, toString, valueOf, values
- hasInstance: Symbol
The symbol used by
instanceof.
- isConcatSpreadable: Symbol
The symbol used by Array.concat(Object...).
- iterator: Symbol
The symbol used by
for...of.
- match: Symbol
The symbol used by String.match(RegExp).
- replace: Symbol
The symbol used by
String.replace().
- search: Symbol
The symbol used by String.search(RegExp).
- species: Symbol
The symbol used to create derived objects.
- split: Symbol
The symbol used by
String.split().
- toPrimitive: Symbol
The symbol used to convert an object to a primitive value.
- toStringTag: Symbol
The symbol used by Object.toString().
- unscopables: Symbol
The symbol used by
with.
- Symbol()
Creates a new symbol. Note that it must be called without
new. Symbols created via this method are always distinct.
- Symbol(description: String)
Creates a new symbol. Note that it must be called without
new. Symbols created via this method are always distinct.Parameters:
- description - A description for this symbol.
- static for(key: String): Symbol
Obtains a symbol from the global registry. If no symbol exists for the key within the registry a new symbol is created and stored in the global registry.
Parameters:
- key - The key for a symbol within the global registry.
Returns:
- The found or newly created symbol.
API Version:
Available from version 21.2.
- static keyFor(symbol: Symbol): String
Returns the key within the global symbol registry under which the given symbol is stored.
Parameters:
- symbol - The symbol to look for.
Returns:
- The key for the given symbol if the symbol is known to the global registry, else return
undefined.