get Set[@@species]

The Set[Symbol.species] accessor property returns the Set constructor.

Description

The species accessor property returns the default constructor for Set objects. Subclass constructors may override it to change the constructor assignment.

Examples

Species in ordinary objects

The species property returns the default constructor function, which is the Set constructor for Set objects:

Set[Symbol.species]; // function Set()

Species in derived objects

In a derived collection object (e.g. your custom set MySet), the MySet species is the MySet constructor. However, you might want to overwrite this, in order to return parent Set objects in your derived class methods:

class MySet extends Set {
  // Overwrite MySet species to the parent Set constructor
  static get [Symbol.species]() { return Set; }
}

Specifications

Specification
ECMAScript (ECMA-262)
The definition of 'get Set [ @@species ]' in that specification.

Browser compatibility

DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
@@speciesChrome Full support 51Edge Full support 13Firefox Full support 41IE No support NoOpera Full support 38Safari Full support 10WebView Android Full support 51Chrome Android Full support 51Firefox Android Full support 41Opera Android Full support 41Safari iOS Full support 10Samsung Internet Android Full support 5.0nodejs Full support 6.5.0
Full support 6.5.0
Full support 6.0.0
Disabled
Disabled From version 6.0.0: this feature is behind the --harmony runtime flag.

Legend

Full support
Full support
No support
No support
User must explicitly enable this feature.
User must explicitly enable this feature.

See also