javascript - IIFE: var vs this - is there any difference? -


is there difference between this , var in invoced function expressions(iife)?

(function(){     var foo = 0;     this.bar = 0; })();

if code executed in global context, 2 options:

  1. you're in use strict mode, , in case this points nothing (null or undefined) , you'll see exception.

  2. you're not in use strict mode , this points window, in case you'll set bar global variable.

var keeps variable local (same scope run in) , not exposed outside calls of iife.


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