From 6f4ff95741b00d88f6d7b38a569d3fab760721a9 Mon Sep 17 00:00:00 2001
From: kemchenj <chenkem95@outlook.com>
Date: Sat, 23 Sep 2017 00:00:43 +0800
Subject: [PATCH] =?UTF-8?q?21=EF=BC=8CExtensions=EF=BC=8Cfor=20Swift=204.0?=
MIME-Version: 1.0
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---
 source/chapter2/21_Extensions.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/source/chapter2/21_Extensions.md b/source/chapter2/21_Extensions.md
index 113dc221..fef872d0 100644
--- a/source/chapter2/21_Extensions.md
+++ b/source/chapter2/21_Extensions.md
@@ -15,6 +15,9 @@
 > 翻译+校对：[SketchK](https://github.com/SketchK) 2016-05-16   
 > 3.0.1，shanks，2016-11-13
 
+> 4.0
+> 校对：[kemchenj](https://kemchenj.github.io/) 2017-09-21
+
 本页包含内容：
 
 - [扩展语法](#extension_syntax)