Bump to v4.0.0.

internal/apply.js

@@ -0,0 +1,22 @@
+/**
+ * A faster alternative to `Function#apply`, this function invokes `func`
+ * with the `this` binding of `thisArg` and the arguments of `args`.
+ *
+ * @private
+ * @param {Function} func The function to invoke.
+ * @param {*} thisArg The `this` binding of `func`.
+ * @param {...*} [args] The arguments to invoke `func` with.
+ * @returns {*} Returns the result of `func`.
+ */
+function apply(func, thisArg, args) {
+  var length = args ? args.length : 0;
+  switch (length) {
+    case 0: return func.call(thisArg);
+    case 1: return func.call(thisArg, args[0]);
+    case 2: return func.call(thisArg, args[0], args[1]);
+    case 3: return func.call(thisArg, args[0], args[1], args[2]);
+  }
+  return func.apply(thisArg, args);
+}
+
+export default apply;