1  var arrayEach = require('./_arrayEach'),
 2      baseCreate = require('./_baseCreate'),
 3      baseForOwn = require('./_baseForOwn'),
 4      baseIteratee = require('./_baseIteratee'),
 5      getPrototype = require('./_getPrototype'),
 6      isArray = require('./isArray'),
 7      isBuffer = require('./isBuffer'),
 8      isFunction = require('./isFunction'),
 9      isObject = require('./isObject'),
10      isTypedArray = require('./isTypedArray');
11  
12  /**
13   * An alternative to `_.reduce`; this method transforms `object` to a new
14   * `accumulator` object which is the result of running each of its own
15   * enumerable string keyed properties thru `iteratee`, with each invocation
16   * potentially mutating the `accumulator` object. If `accumulator` is not
17   * provided, a new object with the same `[[Prototype]]` will be used. The
18   * iteratee is invoked with four arguments: (accumulator, value, key, object).
19   * Iteratee functions may exit iteration early by explicitly returning `false`.
20   *
21   * @static
22   * @memberOf _
23   * @since 1.3.0
24   * @category Object
25   * @param {Object} object The object to iterate over.
26   * @param {Function} [iteratee=_.identity] The function invoked per iteration.
27   * @param {*} [accumulator] The custom accumulator value.
28   * @returns {*} Returns the accumulated value.
29   * @example
30   *
31   * _.transform([2, 3, 4], function(result, n) {
32   *   result.push(n *= n);
33   *   return n % 2 == 0;
34   * }, []);
35   * // => [4, 9]
36   *
37   * _.transform({ 'a': 1, 'b': 2, 'c': 1 }, function(result, value, key) {
38   *   (result[value] || (result[value] = [])).push(key);
39   * }, {});
40   * // => { '1': ['a', 'c'], '2': ['b'] }
41   */
42  function transform(object, iteratee, accumulator) {
43    var isArr = isArray(object),
44        isArrLike = isArr || isBuffer(object) || isTypedArray(object);
45  
46    iteratee = baseIteratee(iteratee, 4);
47    if (accumulator == null) {
48      var Ctor = object && object.constructor;
49      if (isArrLike) {
50        accumulator = isArr ? new Ctor : [];
51      }
52      else if (isObject(object)) {
53        accumulator = isFunction(Ctor) ? baseCreate(getPrototype(object)) : {};
54      }
55      else {
56        accumulator = {};
57      }
58    }
59    (isArrLike ? arrayEach : baseForOwn)(object, function(value, index, object) {
60      return iteratee(accumulator, value, index, object);
61    });
62    return accumulator;
63  }
64  
65  module.exports = transform;