vim - RicoJia/notes GitHub Wiki

Intro

Learn a bit of vim every week! It does take a long time to command. Practice lots.
- Vi is for "visual", vim = Vi + improved. Tailored for Unix systems, and actually vim starts when we start vi.
- Even more ubiquitous than emacs or nano
Vim introduces mode, cuz a key can only function in a certain way: normal, insert, visual (highlight).
vimtutor
Think in vim
- Use hjkl first
- Motion and operator: in dw, d is operator, w is motion.
- There's also count: Count+operator+motion, or operator + count+ motion, like 3D means delete from current cursor 3 times
- READ THE COMMANDS OUT LOUD WILL HELP typing!
- use . for repeated action
- You will see a lot of e vs E, b vs B, the key difference is caps think a word is surrounded by whitespace, while small letters can be surrounded by chars
- Text objects: {operator}a{object} or {operator}i{object}, a means a, i means inside. - E.g,daw(delete word including extra spacing), - diw (delete a word, but keeps spacing) - ciw easiest way to change word - dap deletes a whole paragraph, dip keeps the paragraph boundary, which is a line - das deletes a sentence, diskeeps the sentence boundary, which is a . - da[ or da] deletes everything in a [], while di[, di] keeps the boundary - within a tag cit, cat for angle brackets like <p><\p> - same thing can be used on y: yaw, yiw; yap, yip, yas, yis, ya], yi]
Terminology
- ^f means C-f
- # is to find the last single words, similar to viw, 8

Basic Concepts

Registers: storage locations for yanking
- use :reg, you can see what's in the register
  - :reg z is to see the z register
- "vy is to yank a line into register v
- There are numbered registers 1,2,3.. and registers with chars.
  - "add means to store the line into reg a
  - "Add means to append to a register
  - black hole register: _
  - "" stores the most recently deleted regs
  - "0p means to put from the 0 register, which is the most recent.
- eol stands for end of line

Visual Mode

. means current line

Save a block in visual mode:

 - select using v
 - enter :w FiLENAME #u will see <,>yank, that just means "block"

v, then do 3j to select 3 lines down

Execute normal mode command :

 : <,>,norm i# #Best way to insert comment #, Better than insert block, since it's faster

you can do these operations on the visual mode!
- U is for uppercase, u is for lower case, ~ switch cases
- c for change, like select and delete!
- J for join: join all selected text into one
- gv is to reselect the last selection!!
Tricks
- o to go to the other end of the selection, so you can add stuff to the selection
  - In visual block mode, O is to go to the same end of the line
  - so you can use this to add lines to selection!!
- a is to select the whole paragraph.
Stuff you can do with block visual mode
- I + <Esc> inserts at the beginning of line
- A+<Esc> inserts at the end of selection
- $ + A + <Esc> inserts at the end of every line (not working for line mode, so substitute is developed)
- c change selection to.

Basic Operations

Good cheatsheet: try to practice!!

x for cutting char
Insert
- A is for append at the end of the line, a appends at the end of a char
- I is to insert at the beginning of line
Delete d, gets stored in the "bin register":
- dw: delete word, at the beginning, including the space
- d$: delete everything from the cursor till the end, $ is regex
- de: delete will the end of word, not including space
- db: delete until the beginning of the word
- 3dx: delete 3 chars, 3 dw, delete 3 words
  - 3dd is to delete 3 lines. 3D is to delete 3 lines from the current cursor. it means do dd 3 times
  - ** Hold down x will delete like backspace!!**
- di" delete inside quotes.
- D delete from the cursor to the end of the line
- df<space> is to delete the whole word
- dt char delete everything up to char
undo
- u is to undo a single thing
- U is to undo everything on that line
put & yank
- y (copy) is yank
  - "word." is actually two words, . is a separate word.
  - you can do y2w to yank two lines
  - cut is saved onto a "register", like a clipboard.
- P is put
- -e means edit, that's the edit mode.
- ge, previous word
- Note that . cannot repeat previous navigation motions
replace (mode)
- r: replace a single character, R is to replace multiple char, (also the replace mode)
- s: delete the current char and insert

change, delete and get into the insertion mode, c

ce: change everthing from this char, to the end of the word
c$, c3w ...

- **"in", super cool**
	```
	yis # yank in sentence, here sentence from one . or new line, to the next
	vip	# visual select in paragraph
	vis
	```

Cool tricks
- cw: In insert mode, delete the current word and insert
  - cc, deletes a whole line of text
  - C, deletes the second half of the line
- ~ switches cases!
  - g~~w, g~~$ ... g means group, so you can switch cases here.
  - GUW ... IS TO USE UPPER CASE
  - GUU is to make the entire line uppercase
  - guu is to make everything lowercase
- J means join lines.
- execute external bash commands in vim**
  - :!COMMANDS : means type in a command, ! means an external command. - :r! is to redirect the output of a bash command
- exchange chars: xc
- Insert 80 * in a row: 80I *
  - 80* in a column: 80O *
- save as
  - :w FILENAME
- "Read/Retrieve": -r
  - ```
    1. -r FILE_NAME #paste everything in FILE_NAME to the cursor position
    2. -r !ls       # pase everything from the external command over here, GREAT FOR REPORT!!
```
1. In File Navigation
```
]] (like >>, next), [[ (like going back)goes to the beginning of the next {} (with the outmost indentation)
[], like go back to the previous, then come the end. 
][, like go down to the next {}, then come back to the current's end
```
1. gf: go to file under cursor
Indent and unindent:
```
shift . # do this twice
shift , # do this twice  
get into visual mode, select lines, #indent a block of code
shift . 

gg
=G  # proper indentation. BUT THERE MIGHT BE THINGS IT LEAVES OUT!!
```
- indent
  - i + delim + > pushes everything within the delim >
  - Alignment -left [WIDTH] this align your selected lines to the left, and indent [Width] chars. Default is 80 chars -center [Width] -right[WIDTH]
Appearance
- set ruler/noruler: you can see the line numbers.
- z after search is to change pos

Low Level

<C-W>x = <C_W><C-x>
<C-W><C-V> = :vs; <C_W><C-S> = :s
file ending with rc means "run command"

Advanced

Cursor navigation:
- use ctrl-g can see the current line number if you don't see it
```
  edit /etc/vimrc
  Changed set nocompatible ---> set compatible
```
- jumps ctrl-o, ctrl-I
- going down the end of a line: $, j
- parenthese matching, once u r on a parenthese, hit %, you find the other matching parenthese.
- gg is ceiling, G is ground (bottom of file)
- File Scroll down: C-F, C_B for full pages, C-D, C-U for half page up and down
- H is head, M is the middle part, L is the lower part of the page.
- ^ means jumping to the first char of the line.
  - marks:
    - ma, mb is to set marks. Then you can go to the line with marker: v'a
  - { and } is to jump to the last paragraph, {d} will cut the line above the paragraph and the bottom.
  - '[ and '] will go to the first & last line of pasted text.
  - gJ is to join without space
Substitute:
- :s/old/new/g replace in the same line, globally, else, only the first occurence will be subed
- :a,bs/foo/bar/g from line a to line b:
- :%s/old/new/g sub in the whole file
  - :%s/old/new/gc sub in the whole file and prompts the user.
Search:
- / for forward search, / for backward search
- Vanilla version :START_LINE, END_LINE s///gci...
  - % means all lines
  - . means the current line, $ last line
  - You can also do pattern searching, from line the START_WORD, to line with END_WORD :/START_WORD/./END_WORD/s///gcl
- when you search for special chars like *, you need \
- case insensive:
  - /\c something
  - set ic #ic means ignore case
- set
  - :set hls is #high light search, incremental search
  - :set nohls nois #cancel high light search, incremental search
- f,t, (search for a char in the same line); F,T (searchf for previous char)
  - ; go to the next char
  - t is to stop at the char before
- (shift 8) is to find all occurences of the word the current cursor points to. Then you can hit h.
  - :nohl means no highlight, will turn back on next time.
- exact_match /\<exact_match\>
File navigation
1. go back to previous file: ctrl ^
2. with local .vimrc: move cursor to a file name, then type gf.
3. if you want to switch window, C-W W; quit the window is just :q
  - :vs #vertical split. :vsplit
  - C-W-P previous window
  - C-W-C Close the window
  - C-W-Direction hjkl, arrows, switch windows
  - C-W-O is to close all other windows?
  - vertical window -> horizontal window: ctrl-w shift-h
  - horizontal window -> vertical window: ctrl-w shitf-k
  - neutral sub window size: ctrl-w-=
  - C-W | is to maximize window size
4. Adjust window size:
  - C-W-= All windows with same size
  - C-W-o To maximize a window
Macros: keystrokes you record: good for a specific repeating task!
- q + REG_CHAR, do stuff, , q to stop recording.
  - Make sure your cursor starts at the same place.
  - first go to the beginning of the line, then do your stuff, finally, go to the end of the line
- use macro:
  - @ REG_CHAR to play back
  - @@ means the most current macro, but first, you need to use one
  - :START_LINE, END_LINE normal @REG
- save macros:
  - .viminfo, stores history and non-empty regs
  - in .vimrc:
    - record your Macros in register a
    - let @a = ' ' inside '', just copy your reg content by "ap
      - If you have ' in your macro, use let @char = "... "
  - how to save a macro: qq, then go to vimrc, do "qp

Special CHar

find the corresponding character: insert mode, then hit ctrl-v, and type in the char
You can't type ^[ as , these are two different chars. You have to use ctrl-v to do that

Buffer

Basic flow for buffer and windows

   vim * 
   :ls   # see files in the current buffer
   :b ANOTHER_FILE 
   :wa   #save all files, short for :wall
   :qa!	" quit everthing
   :b# # you are go to the last open file
   :b1 # the 1st item on the buffer. 
   :ls! #you can see hidden files as well
   :bufdo set nu "bufdo is to execute a command on every buffer

By default, files created in buffer is not saved onto the disk yet. You have to save it.
- 3 states: active, and loaded into memory; loaded into memory, not loaded into memory nor being active
  - hidden buffer is fully loaded into the memory, marked withh, it's just not in view.
  - # means previously accessed buffer
  - with set hidden, When you switch away from a buffer and leave, you will be asked to save.
  - :ls! will list ones marked with u, those are unlisted
  - + means modified, but not saved.
- Basic switching
  - :bn " next buffer
  - :- Windows
  - :bf " b first
  - :bl "b last
  - :b tab will cycle thru the buffers
  - :bp "previous Buffer
- Basic Deletions
  - :1,3bd " delete 1,3 buffers
  - :%bd " delete all buffers
  - :bd 1 3delete buffer 1, 3
- Explore
  - :E is to Explore, like nerdtree
  - :bd is to delete the explore buffer and go back

Windows

Basic movements

	```:vs.```  #see all files in the split 
	```:sp```  see fills in horizontal split
	C-W-V #in normal command, create a vertically split window
	C_W-C - close the open window

clipboard
- make sure you have vim-gtk and vim-gnome

Auto-complete

- rn we have installed [clang auto-complete](https://github.com/xavierd/clang_complete)
	ctrl-p / ctrl-n	
- Problems
    - You need C++17, [see here](https://stackoverflow.com/questions/65284572/your-c-compiler-does-not-fully-support-c17)
    - if ymcd server is down, [try this](https://vi.stackexchange.com/questions/26435/the-ycmd-server-shut-down-with-vim-8-1)
    - But you may need vim 8.1+, [see here](https://ubuntuhandbook.org/index.php/2019/12/install-vim-8-2-ubuntu-18-04-16-04-19-10/) 
- file path completion
    you should do ctrl+x + ctrl+f, however we have configured in ~/.vimrc, so you can ctrl-p
- you complete me.
    a. you need to copy .vimrc to every root directory of a project
    b. I downloaded youcompleteme at ~/.vim/bundle
    c. I modified ~/.vimrc for you complete me.
    d. I added .ycm_extra_conf.py in  ~/.vim/bundle/YouCompleteMe

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Plugins