Bump to v3.4.0.

math/sum.js

@@ -0,0 +1,33 @@
+define(['../lang/isArray', '../internal/toIterable'], function(isArray, toIterable) {
+
+  /**
+   * Gets the sum of the values in `collection`.
+   *
+   * @static
+   * @memberOf _
+   * @category Math
+   * @param {Array|Object|string} collection The collection to iterate over.
+   * @returns {number} Returns the sum.
+   * @example
+   *
+   * _.sum([4, 6, 2]);
+   * // => 12
+   *
+   * _.sum({ 'a': 4, 'b': 6, 'c': 2 });
+   * // => 12
+   */
+  function sum(collection) {
+    if (!isArray(collection)) {
+      collection = toIterable(collection);
+    }
+    var length = collection.length,
+        result = 0;
+
+    while (length--) {
+      result += +collection[length] || 0;
+    }
+    return result;
+  }
+
+  return sum;
+});