Bump to v4.0.0.

assign.js

@@ -0,0 +1,38 @@
+define(['./internal/copyObject', './internal/createAssigner', './keys'], function(copyObject, createAssigner, keys) {
+
+  /**
+   * Assigns own enumerable properties of source objects to the destination
+   * object. Source objects are applied from left to right. Subsequent sources
+   * overwrite property assignments of previous sources.
+   *
+   * **Note:** This method mutates `object` and is loosely based on
+   * [`Object.assign`](https://mdn.io/Object/assign).
+   *
+   * @static
+   * @memberOf _
+   * @category Object
+   * @param {Object} object The destination object.
+   * @param {...Object} [sources] The source objects.
+   * @returns {Object} Returns `object`.
+   * @example
+   *
+   * function Foo() {
+   *   this.c = 3;
+   * }
+   *
+   * function Bar() {
+   *   this.e = 5;
+   * }
+   *
+   * Foo.prototype.d = 4;
+   * Bar.prototype.f = 6;
+   *
+   * _.assign({ 'a': 1 }, new Foo, new Bar);
+   * // => { 'a': 1, 'c': 3, 'e': 5 }
+   */
+  var assign = createAssigner(function(object, source) {
+    copyObject(source, keys(source), object);
+  });
+
+  return assign;
+});