Bump to v4.0.0.

toIterator.js

@@ -0,0 +1,25 @@
+define([], function() {
+
+  /**
+   * Enables the wrapper to be iterable.
+   *
+   * @name Symbol.iterator
+   * @memberOf _
+   * @category Seq
+   * @returns {Object} Returns the wrapper object.
+   * @example
+   *
+   * var wrapped = _([1, 2]);
+   *
+   * wrapped[Symbol.iterator]() === wrapped;
+   * // => true
+   *
+   * Array.from(wrapped);
+   * // => [1, 2]
+   */
+  function wrapperToIterator() {
+    return this;
+  }
+
+  return wrapperToIterator;
+});