In JavaScript, is chained assignment okay?

Question

Am not new to JS or its syntax, but sometimes, the semantics of the language has me stumped at times. At work today, a colleague mentioned this:

var a = b =          


        

Answer 1

Your colleague is right:

var a = b = [];
a.push('something');
console.log(b);          // outputs ["something"]

but:

var a = [], b = [];
a.push('something');
console.log(b);          // outputs []