function arrayMap(array, iteratee) {
    var index = -1,
        length = array.length,
        result = Array(length);

    while (++index < length) {
      result[index] = iteratee(array[index], index, array);
    }
    return result;
  }
A specialized version of `_.map` for arrays without support for callback
shorthands or `this` binding.

@private
@param {Array} array The array to iterate over.
@param {Function} iteratee The function invoked per iteration.
@returns {Array} Returns the new mapped array.