Cannot extend ES6 classes: Class constructors cannot be invoked without 'new'

[balupton]

Just did this repo to test interopability between CoffeeScript and ES6 classes: https://github.com/balupton/javascript-coffeescript-class-interop

However it turns out that while ES6 classes can extend CoffeeScript classes, CoffeeScript cannot extend ES6 classes due to the error: Class constructors cannot be invoked without 'new'

As ES6 becomes more widely adopted, this seems to be a large interop issue.

[Zorgatone]

+1 👍

[GeoffreyBooth]

Closing in favor of #4233. (I know it came later, but it has more discussion.)

Addressed by #4354.