Projekt

Obecné

Profil

Stáhnout (1.76 KB) Statistiky
| Větev: | Revize:
1
var arrayReduce = require('./_arrayReduce'),
2
    baseEach = require('./_baseEach'),
3
    baseIteratee = require('./_baseIteratee'),
4
    baseReduce = require('./_baseReduce'),
5
    isArray = require('./isArray');
6

    
7
/**
8
 * Reduces `collection` to a value which is the accumulated result of running
9
 * each element in `collection` thru `iteratee`, where each successive
10
 * invocation is supplied the return value of the previous. If `accumulator`
11
 * is not given, the first element of `collection` is used as the initial
12
 * value. The iteratee is invoked with four arguments:
13
 * (accumulator, value, index|key, collection).
14
 *
15
 * Many lodash methods are guarded to work as iteratees for methods like
16
 * `_.reduce`, `_.reduceRight`, and `_.transform`.
17
 *
18
 * The guarded methods are:
19
 * `assign`, `defaults`, `defaultsDeep`, `includes`, `merge`, `orderBy`,
20
 * and `sortBy`
21
 *
22
 * @static
23
 * @memberOf _
24
 * @since 0.1.0
25
 * @category Collection
26
 * @param {Array|Object} collection The collection to iterate over.
27
 * @param {Function} [iteratee=_.identity] The function invoked per iteration.
28
 * @param {*} [accumulator] The initial value.
29
 * @returns {*} Returns the accumulated value.
30
 * @see _.reduceRight
31
 * @example
32
 *
33
 * _.reduce([1, 2], function(sum, n) {
34
 *   return sum + n;
35
 * }, 0);
36
 * // => 3
37
 *
38
 * _.reduce({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
39
 *   (result[value] || (result[value] = [])).push(key);
40
 *   return result;
41
 * }, {});
42
 * // => { '1': ['a', 'c'], '2': ['b'] } (iteration order is not guaranteed)
43
 */
44
function reduce(collection, iteratee, accumulator) {
45
  var func = isArray(collection) ? arrayReduce : baseReduce,
46
      initAccum = arguments.length < 3;
47

    
48
  return func(collection, baseIteratee(iteratee, 4), accumulator, initAccum, baseEach);
49
}
50

    
51
module.exports = reduce;
(526-526/634)