Update go-extension.md

taowen · web-flow · commit 877d6d8d73ea · 2016-12-19T22:49:08.000+08:00
diff --git a/go-extension.md b/go-extension.md
@@ -3,6 +3,8 @@ layout: default
 title: How to extend
 ---
 
+* TOC
+{:toc}
 
 # Bind-api extension
 
