"use strict";

var _foo, _foo$bar, _foo$bar2;
var _defaults = function (obj, defaults) {
  for (var key in defaults) {
    if (obj[key] === undefined) {
      obj[key] = defaults[key];
    }
  }

  return obj;
};

console.log((_foo = foo, _defaults(_foo, bar), _foo));

console.log((_foo$bar = foo[bar], _defaults(_foo$bar, bar), _foo$bar));

console.log((_foo$bar2 = foo[bar()], _defaults(_foo$bar2, bar), _foo$bar2));