Bump to v3.0.0.

collection/reduce.js

@@ -0,0 +1,40 @@
+import arrayReduce from '../internal/arrayReduce';
+import baseCallback from '../internal/baseCallback';
+import baseEach from '../internal/baseEach';
+import baseReduce from '../internal/baseReduce';
+import isArray from '../lang/isArray';
+
+/**
+ * Reduces `collection` to a value which is the accumulated result of running
+ * each element in `collection` through `iteratee`, where each successive
+ * invocation is supplied the return value of the previous. If `accumulator`
+ * is not provided the first element of `collection` is used as the initial
+ * value. The `iteratee` is bound to `thisArg`and invoked with four arguments;
+ * (accumulator, value, index|key, collection).
+ *
+ * @static
+ * @memberOf _
+ * @alias foldl, inject
+ * @category Collection
+ * @param {Array|Object|string} collection The collection to iterate over.
+ * @param {Function} [iteratee=_.identity] The function invoked per iteration.
+ * @param {*} [accumulator] The initial value.
+ * @param {*} [thisArg] The `this` binding of `iteratee`.
+ * @returns {*} Returns the accumulated value.
+ * @example
+ *
+ * var sum = _.reduce([1, 2, 3], function(sum, n) { return sum + n; });
+ * // => 6
+ *
+ * var mapped = _.reduce({ 'a': 1, 'b': 2, 'c': 3 }, function(result, n, key) {
+ *   result[key] = n * 3;
+ *   return result;
+ * }, {});
+ * // => { 'a': 3, 'b': 6, 'c': 9 } (iteration order is not guaranteed)
+ */
+function reduce(collection, iteratee, accumulator, thisArg) {
+  var func = isArray(collection) ? arrayReduce : baseReduce;
+  return func(collection, baseCallback(iteratee, thisArg, 4), accumulator, arguments.length < 3, baseEach);
+}
+
+export default reduce;