In DF (server side) we have the Mixin class, which is quite useful to combine isolated features into a single new sub-class.

What is the equivalent for that in JavaScript that is supported by WAF, or making the same question in a different way.. What is the WAF way of doing it !?

I've analyzed several df.* built-in in js class looking for any clue, but still didn't find it..

Is it even possible ?