addEventListener/removeEventListener non-optional arguments

For a very long time, the first two arguments (type and listener) of addEventListener and removeEventListener have been optional, where they are non-optional in the spec and other browsers. This will change, so that calling these methods with zero or one argument will start to throw exceptions.

Demo

• https://googlechrome.github.io/samples/event-listeners-mandatory-arguments/index.html

Documentation

• https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener
• https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/removeEventListener

Specification

Established standard

Status in Chromium

Blink components: Blink

Enabled by default (launch bug) in:

• Chrome for desktop release 49
• Chrome for Android release 49
• Android WebView release 49
• Opera release 36
• Opera for Android release 36

Consensus & Standardization

• Firefox: Shipped
• Edge: Shipped
• Safari: No public signals
• Web Developers: No signals

Owner

• philipj@opera.com

Last updated on 2017-06-14