ES2015 changes the semantics of Arrays and certain other classes to create subclass instances from certain methods, and allow a new interception point, Symbol.species, to control whether it's actually the subclass or another class which is instantiated. For example, Array.prototype.map constructs instances of the subclass as its output, with the option to customize this by changing Symbol.species

Documentation

Specification

Established standard

Status in Chromium

Blink


Enabled by default (tracking bug) in:

  • Chrome for desktop release 51

Consensus & Standardization

After a feature ships in Chrome, the values listed here are not guaranteed to be up to date.

Owner

Last updated on 2020-11-09