phpjs/functions/array/array_fill_keys.js

php.js offers community built php functions in javascript

function array_fill_keys(keys, value) {
  //  discuss at: http://phpjs.org/functions/array_fill_keys/
  // original by: Brett Zamir (http://brett-zamir.me)
  // bugfixed by: Brett Zamir (http://brett-zamir.me)
  //   example 1: keys = {'a': 'foo', 2: 5, 3: 10, 4: 'bar'}
  //   example 1: array_fill_keys(keys, 'banana')
  //   returns 1: {"foo": "banana", 5: "banana", 10: "banana", "bar": "banana"}

  var retObj = {},
    key = '';

  for (key in keys) {
    retObj[keys[key]] = value;
  }

  return retObj;
}