code: function arrayMap(array, callback) {
        var index = -1,
            length = array ? array.length >>> 0 : 0,
            result = Array(length);
  
        while (++index < length) {
          result[index] = callback(array[index], index, array);
        }
        return result;
      }
docs: 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} callback The function called per iteration.
  @returns {Array} Returns the new mapped array.