Bump to v4.0.0.

wrapperFlatMap.js

@@ -0,0 +1,22 @@
+/**
+ * This method is the wrapper version of `_.flatMap`.
+ *
+ * @static
+ * @memberOf _
+ * @category Seq
+ * @param {Function|Object|string} [iteratee=_.identity] The function invoked per iteration.
+ * @returns {Object} Returns the new `lodash` wrapper instance.
+ * @example
+ *
+ * function duplicate(n) {
+ *   return [n, n];
+ * }
+ *
+ * _([1, 2]).flatMap(duplicate).value();
+ * // => [1, 1, 2, 2]
+ */
+function wrapperFlatMap(iteratee) {
+  return this.map(iteratee).flatten();
+}
+
+export default wrapperFlatMap;