get Set[@@species]

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




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


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

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

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; }


Specification Status Comment
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'get Set [ @@species ]' in that specification.
Standard Initial definition.
ECMAScript 2017 Draft (ECMA-262)
The definition of 'get Set [ @@species ]' in that specification.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support No support 41 (41) No support No support No support
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support No support 41.0 (41) No support No support No support

See also

Document Tags and Contributors

 Contributors to this page: fscholz, arai
 Last updated by: fscholz,