Configuring vim

apt-get install vim

vim is called 编辑器之神. You will use vim for coding in all PAs and Labs, as well as editing other files. Maybe some of you prefer to other editors requiring GUI environment (such Visual Studio). However, you can not use them in some situations, especially when you are accessing a physically remote server:

• the remote server does not have GUI installed, or
• the network condition is so bad that you can not use any GUI tools.

Under these situations, vim is still a good choice. Another reason to choose vim is that, vim can greatly improve your coding efficiency. If you prefer to emacs, you can download and install emacs from network mirrors.

Learning vim

You are going to be asked to modify a file using vim. For most of you, this is the first time to use vim. The operations in vim are quite different from other editors you have ever used. To learn vim, you need a tutorial. There are two ways to get tutorials:

• Issue the vimtutor command in terminal. This will launch a tutorial for vim.This way is recommended, since you can read the tutorial and practice at the same time.
• Search the Internet with keyword "vim 教程", and you will find a lot of tutorials about vim. Choose some of them to read, meanwhile you can practice with the a temporary file by

  vim test
  

1
2
3
.....
98
99
100

i1<ESC>q1yyp<C-a>q98@1

i1<ESC>q1yyp<C-a>q998@1

aaaaaaaaaaaaaaaaaaaaaaaaabbbbbbbbbbbbbbbbbbbbbbbbb
cccccccccccccccccccccccccddddddddddddddddddddddddd
eeeeeeeeeeeeeeeeeeeeeeeeefffffffffffffffffffffffff
ggggggggggggggggggggggggghhhhhhhhhhhhhhhhhhhhhhhhh
iiiiiiiiiiiiiiiiiiiiiiiiijjjjjjjjjjjjjjjjjjjjjjjjj

bbbbbbbbbbbbbbbbbbbbbbbbbaaaaaaaaaaaaaaaaaaaaaaaaa
dddddddddddddddddddddddddccccccccccccccccccccccccc
fffffffffffffffffffffffffeeeeeeeeeeeeeeeeeeeeeeeee
hhhhhhhhhhhhhhhhhhhhhhhhhggggggggggggggggggggggggg
jjjjjjjjjjjjjjjjjjjjjjjjjiiiiiiiiiiiiiiiiiiiiiiiii

<C-v>24l4jd$p

<C-v>24l99jd$p

Enabling syntax highlight

vim provides more improvements comparing with vi. But these improvements are disabled by default. Therefore, you should enable them first.

We take syntax highlight as an example to illustrate how to enable the features of vim. To do this, you should modify the vim configuration file. The file is called vimrc, and it is located under /etc/vim directory. We first make a copy of it to the home directory by cp command:

cp /etc/vim/vimrc ~/.vimrc

And switch to the home directory if you are not under it yet:

cd ~

If you use ls to list files, you will not see the .vimrc you just copied. This is because a file whose name starts with a . is a hidden file in GNU/Linux. To show hidden files, use ls with -a option:

ls -a

Then open .vimrc using vim:

vim .vimrc

After you learn some basic operations in vim (such as moving, inserting text, deleting text), you can try to modify the .vimrc file as following:

--- before modification
+++ after modification
@@ -17,3 +17,3 @@
 " Vim5 and later versions support syntax highlighting. Uncommenting the next
 " line enables syntax highlighting by default.
-"syntax on
+syntax on

We present the modification with GNU diff format. If you do not understand the diff format, please search the Internet for more information.

After you are done, you should save your modification. Exit vim and open the vimrc file again, you should see the syntax highlight feature is enabled.

Enabling more vim features

Modify the .vimrc file mentioned above as the following:

--- before modification
+++ after modification
@@ -21,3 +21,3 @@
 " If using a dark background within the editing area and syntax highlighting
 " turn on this option as well
-"set background=dark
+set background=dark
@@ -31,5 +31,5 @@
 " Uncomment the following to have Vim load indentation rules and plugins
 " according to the detected filetype.
-"if has("autocmd")
-"  filetype plugin indent on
-"endif
+if has("autocmd")
+  filetype plugin indent on
+endif
@@ -37,10 +37,10 @@
 " The following are commented out as they cause vim to behave a lot
 " differently from regular Vi. They are highly recommended though.
 "set showcmd            " Show (partial) command in status line.
-"set showmatch          " Show matching brackets.
-"set ignorecase         " Do case insensitive matching
-"set smartcase          " Do smart case matching
-"set incsearch          " Incremental search
+set showmatch          " Show matching brackets.
+set ignorecase         " Do case insensitive matching
+set smartcase          " Do smart case matching
+set incsearch          " Incremental search
 "set autowrite          " Automatically save before commands like :next and :make
-"set hidden             " Hide buffers when they are abandoned
+set hidden             " Hide buffers when they are abandoned
 "set mouse=a            " Enable mouse usage (all modes)

You can append the following content at the end of the .vimrc file to enable more features. Note that contents after a double quotation mark " are comments, and you do not need to include them. Of course, you can inspect every features to determine to enable or not.

setlocal noswapfile " 不要生成swap文件
set bufhidden=hide " 当buffer被丢弃的时候隐藏它
colorscheme evening " 设定配色方案
set number " 显示行号
set cursorline " 突出显示当前行
set ruler " 打开状态栏标尺
set shiftwidth=4 " 设定 << 和 >> 命令移动时的宽度为 4
set softtabstop=4 " 使得按退格键时可以一次删掉 4 个空格
set tabstop=4 " 设定 tab 长度为 4
set nobackup " 覆盖文件时不备份
set autochdir " 自动切换当前目录为当前文件所在的目录
set backupcopy=yes " 设置备份时的行为为覆盖
set hlsearch " 搜索时高亮显示被找到的文本
set noerrorbells " 关闭错误信息响铃
set novisualbell " 关闭使用可视响铃代替呼叫
set t_vb= " 置空错误铃声的终端代码
set matchtime=2 " 短暂跳转到匹配括号的时间
set magic " 设置魔术
set smartindent " 开启新行时使用智能自动缩进
set backspace=indent,eol,start " 不设定在插入状态无法用退格键和 Delete 键删除回车符
set cmdheight=1 " 设定命令行的行数为 1
set laststatus=2 " 显示状态栏 (默认值为 1, 无法显示状态栏)
set statusline=\ %<%F[%1*%M%*%n%R%H]%=\ %y\ %0(%{&fileformat}\ %{&encoding}\ Ln\ %l,\ Col\ %c/%L%) " 设置在状态行显示的信息
set foldenable " 开始折叠
set foldmethod=syntax " 设置语法折叠
set foldcolumn=0 " 设置折叠区域的宽度
setlocal foldlevel=1 " 设置折叠层数为 1
nnoremap <space> @=((foldclosed(line('.')) < 0) ? 'zc' : 'zo')<CR> " 用空格键来开关折叠