libs/lodash.js
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;
    }
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;
    }
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 ; }
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.
A specialized version of _ . map for arrays without support for callback shorthands or this binding .