Array subclassing and Symbol.species support

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, constructs instances of the subclass as its output, with the option to customize this by changing Symbol.species



Established standard

Status in Chromium


Enabled by default (tracking bug) in:

  • Chrome for desktop release 51
  • Opera release 38
  • Opera for Android release 38

Consensus & Standardization


Last updated on 2017-06-14