map.js

var arrayMap = require('./_arrayMap'),
    baseIteratee = require('./_baseIteratee'),
    baseMap = require('./_baseMap'),
    isArray = require('./isArray');

/**
 * Creates an array of values by running each element in `collection` thru
 * `iteratee`. The iteratee is invoked with three arguments:
 * (value, index|key, collection).
 *
 * Many lodash methods are guarded to work as iteratees for methods like
 * `_.every`, `_.filter`, `_.map`, `_.mapValues`, `_.reject`, and `_.some`.
 *
 * The guarded methods are:
 * `ary`, `chunk`, `curry`, `curryRight`, `drop`, `dropRight`, `every`,
 * `fill`, `invert`, `parseInt`, `random`, `range`, `rangeRight`, `repeat`,
 * `sampleSize`, `slice`, `some`, `sortBy`, `split`, `take`, `takeRight`,
 * `template`, `trim`, `trimEnd`, `trimStart`, and `words`
 *
 * @static
 * @memberOf _
 * @since 0.1.0
 * @category Collection
 * @param {Array|Object} collection The collection to iterate over.
 * @param {Function} [iteratee=_.identity] The function invoked per iteration.
 * @returns {Array} Returns the new mapped array.
 * @example
 *
 * function square(n) {
 *   return n * n;
 * }
 *
 * _.map([4, 8], square);
 * // => [16, 64]
 *
 * _.map({ 'a': 4, 'b': 8 }, square);
 * // => [16, 64] (iteration order is not guaranteed)
 *
 * var users = [
 *   { 'user': 'barney' },
 *   { 'user': 'fred' }
 * ];
 *
 * // The `_.property` iteratee shorthand.
 * _.map(users, 'user');
 * // => ['barney', 'fred']
 */
function map(collection, iteratee) {
  var func = isArray(collection) ? arrayMap : baseMap;
  return func(collection, baseIteratee(iteratee, 3));
}

module.exports = map;