update doc

README.cn.md

@@ -263,21 +263,9 @@ PS：你可以使用 `$_ZL_FZF` 环境变量来精确指明 fzf 的可执行路
 
 `"-b"` 选项可以快速回到某一级父目录，避免重复的输入 "cd ../../.."。
 
-- **(没有参数)** `cd` 到项目根目录：
-  
-  使用 `"z -b"` 后面不跟任何参数，z.lua 会寻找当前项目的 checkout 目录（有 `.git`/`.hg`/`.svn` 的地方） 然后 `cd` 过去。
-
-- **(单个参数)** `cd` 到离当前目录最近的以关键字开头的父目录：
-
-  假设你在 `/home/user/project/src/org/main/site/utils/file/reader/whatever` 然后你想快速回到 `site` 目录，
-
-  只需要输入：`z -b site`
-
-  实际上，可简化为 `z -b <开头的几个字母>` 比如 `z -b s` 或者 `z -b si`。
-  
-  如果当前存在多级父目录同时包含你输入的关键词，`z -b xxx` 会将你到离你最近的那一层父目录。
-
-- **(两个参数)** 将当前路径中的第一个关键词替换为第二个关键词。
+- **(没有参数)**：`cd` 到项目根目录，即跳转到父目录中包含 (.git/.svn/.hg) 的地方。
+- **(单个参数)**：`cd` 到离当前目录最近的以关键字开头的父目录。
+- **(两个参数)**：将当前路径中的第一个关键词替换为第二个关键词。
 
 为了使用简便，我们继续将 `z -b` 取个别名成 `zb`：
 
@@ -290,6 +278,10 @@ PS：你可以使用 `$_ZL_FZF` 环境变量来精确指明 fzf 的可执行路
 ~/github/vimium/src/public$ zb g
   => cd ~/github
 
+# 快速回到 site 目录
+~/github/demo/src/org/main/site/utils/file/reader/whatever$ zb si
+  => cd ~/github/demo/src/org/main/site
+
 # 将 jekyll 替换为 ghost
 ~/github/jekyll/test$ zb jekyll ghost
   => cd ~/github/ghost/test

README.md

@@ -277,20 +277,9 @@ NOTE: For fish shell, this feature requires fish 2.7.0 or above. You can specify
 
 New option `"-b"` can quickly go back to a specific parent directory in bash instead of typing "cd ../../.." redundantly.
 
-- **(No argument)** `cd` into the project root:
-
-  Use `z -b` with no argument, it will look for the project (checkout) directory (the one with `.git`/`.hg`/`.svn` in it) and then `cd` into it.
-
-- **(One argument)** `cd` into the closest parent having its name begin with whatever the value you passed in:
-
-  If you are in this path `/home/user/project/src/org/main/site/utils/file/reader/whatever` and you want to go to `site` directory quickly, 
-
-  then just type: `z -b site`
-
-  In fact, You can simply type `z -b <starting few letters>` like `z -b s` or `z -b si`.
-  If there are more than one directories with same name up in the hierarchy, `z -b` will take you to the closest. 
-
-- **(Two arguments)** replace the first value with the second one (in the current path).
+- **(No argument)**: `cd` into the project root, the project root is one of the parent directory with `.git`/`.hg`/`.svn` in it
+- **(One argument)**: `cd` into the closest parent having its name begin with the keyword you passed in.
+- **(Two arguments)**: replace the first value with the second one (in the current path).
 
 Let's start by aliasing `z -b` to `zb`:
 
@@ -303,6 +292,10 @@ Let's start by aliasing `z -b` to `zb`:
 ~/github/vimium/src/public$ zb g
   => cd ~/github
 
+# goto the site directory quickly
+~/github/demo/src/org/main/site/utils/file/reader/whatever$ zb si
+  => cd ~/github/demo/src/org/main/site
+
 # substitute jekyll with ghost
 ~/github/jekyll/test$ zb jekyll ghost
   => cd ~/github/ghost/test