how to unindent in vim without leaving edit mode? - vim

I'm writing a lot of python code recently, and i used the tab-to-space mode in vim. I was just wondering how would i unindent in vim without leaving edit mode for example after i finished if...: block. Normally I can just type << to unindent, but it takes too many keystorkes, anyone have a better idea?

Type Ctrl-D on your keyboard, removes one tabstop at a time, works for space-replaced tabs.

In Vim in Linux you can unindent multiple lines by using V to select your first line. Press the down arrow to select multiple lines. Then type < to unindent all of the lines.
If you want to indent, type > instead

Backspace will remove one level of indent at a time.

You can press Ctrl-U it will delete backwards to the beginning of line.

Related

How to get delete-button behavior in vim?

When using vim in insert mode (or not using vim at all), pressing the delete-button deletes a character TO THE RIGHT of the cursor. How can I get this behavior in vim when in normal mode?
Pressing x is not the right answer as it deletes the selected character, not the character to the right.
In the Insert mode it's just for you the cursor looks "kinda between characters". But in fact, your computer sees it being right on the character you are deleting.
In the Normal mode you normally have the bar-cursor, so it looks the way it works.
Now, of course, you can remap your "x" to delete the char to the right, but it will only add a confusion. So, please, don't. Train your mind to see the things in the proper light instead.

How to efficiently add parentheses or a string in vim?

In traditional text editors, whenever I needed to open a string or parentheses and type something between it I used to do:
Type () or ""
Press left
Type in what I need
Press right
But in vim (that is if I followed the vim way) the process becomes quite tedious as I have to enter the normal mode to move a whole bunch of times:
Type () or ""
Press <ESC>
Press i
Type what I need
Press <ESC>
Press l
Press a
If it is not a good practice to use the arrow keys at any time, is there a more efficient way of doing this kind of task in vim?
It is actually quite easy to automatically append those closing characters in a mapping, and put your cursor where you want it. The trick is to do that, without also messing up the undo/redo/repeat actions. The problem is that cursor movement commands in insert mode will break the "undo sequence" so that any change you make after moving the cursor is undone separately from changes made before moving the cursor.
Warning: the following information may become dated
There are plenty of plugins available to automatically append these characters (see the partial list at the Vim wiki page for appending closing characters), and prior to Vim 7.4, some of them even had complicated workarounds for keeping the undo sequence intact. Unfortunately, they all relied on a bug in Vim that got fixed in version 7.4 for this.
A patch is available to add a cursor movement that does not break undo, so if you want to compile Vim yourself, you can grab that patch and use mappings like the following (no plugin required!) to do what you want:
inoremap ( ()<C-G>U<Left>
inoremap <expr> ) strpart(getline('.'), col('.')-1, 1) == ")" ? "\<C-G>U\<Right>" : ")"
These mappings will insert "()" when you type an opening (, placing the cursor in between the parentheses. When you type ')' and there is already a closing ')' after the cursor, Vim will skip over the parenthesis instead of inserting a new one. Cursor movement is preceded by <C-G>U which is the feature the aforementioned patch adds, allowing the following cursor movement to not break the undo sequence (as long as the movement is all in a single line).
As of Vim 7.4.663, this patch has still not been officially included.
No. Doing it in Vim is exactly the same as in your "traditional" editor:
Type () or ""
Press left
Type in what you need
Press right
But… why don't you type the opening character, what you want inside the pair and then the closing character?
Type ( or "
Type what you need
Type ) or "
Too simple?
I think using arrow keys to move around is bad practice in normal mode but in your case; moving one space while in insert mode, I would hazard to say using the arrow keys is probably best practice.
That being said if you are dead set on avoiding them you could use <i_ctrl-o>.
:help i_ctrl_o
CTRL-O execute one command, return to Insert mode *i_CTRL-O*
So, while in insert mode, you could type: ()<ctrl-o>h<xxx><ctrl-o>l, where <xxx> is whatever you want in the brackets.
Unfortunately that doesn't work if you cursor is on the last character of the line, which if you are typing it most likely is.
To solve that problem do :set virtualedit+=onemore or add it to your ~/.vimrc file.
Note that this solution is more keystrokes than simply using the arrow keys but you don't need to move your hands away from the home row so it may be faster anyway.

How to go back to previous indentation level in insert mode?

Sometimes vim's smartindent does not pick the correct level of indentation for the next line once you hit enter and you'd like to go back to the indentation level of the previous line and just go from there. I know that you can hit ctrl-d a few times to achieve this but it would be more useful for a key that immediately goes to the indentation level of the line above.
I don't know if it's pure coincidence, but Alexey Radev has just published the prev_indent plugin, which provides an insert mode mapping and :PrevIndent command to move the current line to the previous indentation level.
If you can't be bothered to install a plugin for such a simple task (I couldn't), try this simple mapping:
:inoremap <C-D> <Esc>:call setline(".",substitute(getline(line(".")),'^\s*',matchstr(getline(line(".")-1),'^\s*'),''))<CR>I
Now CtrlD in insert mode will do the deed: indent the current line like the previous line.
This works best before you start typing on the new line, because it will reset the cursor to just past the indentation.
In normal mode you can use < and > to increase or decrease indentation. They work as expected with movements, visual selection and >> << for the current line. You can also use = to chose the "correct" indentation level, again it works as expected with regards to movements etc.
So what I usually do is fix indentation errors in normal mode after I'm done editing, by a combination of block selecting and using =, and then fixing individual lines with << and >>.
You can use <C-O>=G to indent from cursor to end of file in insert mode. Or <C-O><< to remove one indentation level.

Opposite of newline in vim

In vim, is there a command to delete the newline, and all empty space behind the cursor?
Say I stand in the middle of a text in insert mode and press Enter, what command would the reverse what I just did?
A) An example:
"some code{ in here }"
B) After pressing Enter:
"some code{
in here }"
Now pressing backspace will delete one space of the indentation. I would rather have it delete all indentation, and jump back to A.
Can this be done in a command or by doing some remapping to the backspace key?
It's tragic how unknown the J command is. It joins lines in normal mode.
In insert mode, you can press <C-U> twice; first, it'll delete the indent before the cursor, then it'll join with the previous line. Note that this requires
:set backspace=indent,eol,start
did you try J (uppercase) ? it will give exactly what you want.
"some code{ cursor on this line, pressJ
in here }"
You can do ᴇꜱᴄ, K, Shift+J.
K jumps up to the previous line and Shift+J joins the two lines.
However, with properly configured indentation and syntax, a backspace doesn’t just delete a space, it deletes the full previous indentation block.
One easy way is up one line, to end of that line and just delete. As long as you still are in insert mode it will do the same thing as J when deleting at the last position - like most other editors. For me that is the quickest alternative because I'm used to it from other editors.
That is: ↑, End, Delete (when still in insert mode)
One quick alternative (the VIM-way) is (when still in insert mode):
↑, Ctrl+o, J (when still in insert mode)
(Ctrl+o is used in insert mode to enter one normal mode command.)
It's also possible to use a remapping of the backspace key:
inoremap <expr> <bs> getline('.')[:col('.')-2]=~'^\s\+$' ? "<c-u><c-u>" : "<bs>"
Note that this mapping completely overrides the normal behavior the backspace key. This will only be useful when you don't intend to use its normal behavior. This is not recommended if you can easily access the other options (c-u or J)
However, (as far as I know) there's no way to distinguish between manually added leading white spaces and auto indent. If you use noexpandtab, you can edit the regex to only match tabs.
This also does not work in some modes of auto-indent (for example, in block comment in C, vim automatically start a new line starts with *)

Vim / vi Survival Guide

What are the essential vim commands? What does a new-user need to know to keep themselves from getting into trouble? One command per comment, please.
What I find irreplaceable (because it works in vi also, unlike vim's visual mode) are marks. You can mark various spots with m (lower case) and then a letter of your choice (eg x). Then you go elsewhere, and can go back with ``x(backquote letter) to the exact spot, or with'x` (apostrophe letter) to go to the line.
These movements can be used as arguments to commands (yank, delete, etc). For example, you want to delete 10 lines; instead of counting and then moving to the topmost line and entering 10dd, you go to either the start or the end of the block, press mm (mark m), then go to the other end of the block, and press d'm (delete apostrophe m). If you use backquote instead of apostrophe in this example, then the deletion will work character-wise, not line-wise. Try marking in the middle of the line with "mark m", moving to the middle of another line, then entering "d backquote m" and you will see what I mean.
I was very happy the day I learned about using * or # to search, down or up respectively, for the word under the cursor. Make sure to :set incsearch and :set hlsearch first.
I like this QRC!
http://www.fsckin.com/wp-content/uploads/2007/10/vi-vim_cheat_sheet.gif
When you have some repetitive action to take Macros are usually faster than regex.
Just type
q[0-9a-z] in normal mode
Many people use
qq
because it's fast.
Press
q in normal mode
again to stop recording.
Then just type
#[0-9a-z] in normal mode
to repeat what you just recorded.
#q
for the example like above.
Edited to add: you can also repeat the macro. Let's say you programed a macro to jump to the head of a line, insert a tab, and then jump down one line. You then test your macro by typing "#q" to run it once. Then you can repeat the action nine more times by typing "9#q".
:q -> quit
:w -> save
:q! -> quit and don't save
:x -> save and quit
:[number] -> go to line number
G -> go to end of file
dd -> delete line
p -> "put" line
yy -> "copy" line
:s/[searchfor] -> search
I guess those are the basic one to start from
Use the 'J' (J for Join; upper-case) command to delete the newline at the end of a line. You'll find it tricky otherwise.
This recent Vim tutorial from IBM is pretty good
First of all you need to know how to close vi:
ctrl-c : q!
Rest can be found from vimtutor. Launch vimtutor by typing vimtutor at your command line
Although this is a matter of personal preference I've found that one of the essential things to do is to remap Esc to something else.
I find it very uncomfortable to reach for the Esc key to exit insert mode, but the beautiful thing about Vim is that allows key mappings.
I'm currently using the following mapping using Control + S:
inoremap <C-s> <Esc>:w<CR>
This has the advantage of being a key mapping I have already committed to memory and has the added value of saving my work every time I go to normal mode. Yeah, I know it is crazy but I would be hitting the save command that frequently anyway. It's like a bad habit, you know.
" ~/.vimrc
" Turn on line numbering
set nu
" Turn on syntax highlighting
syntax on
" Set 4 space expanding tabs
set tabstop=4
set shiftwidth=4
set softtabstop=4
set expandtab
"turn off line wrapping
set nowrap
" Map CTRL-N to create a new tab
:map <C-n> <ESC>:tabnew<RETURN>
" Map Tab and CTRL-Tab to move between tabs
:map <Tab> <ESC>:tabn<RETURN>
:map <C-Tab> <ESC>:tabp<RETURN>
If you're using vim, the 'u' command (in command mode) will Undo the last command you typed. You can use this command repeatedly to undo mistakes you may have made before saving the file.
See http://www.rayninfo.co.uk/vimtips.html for a great collection of Vim tips, from the basic can't-live-without to very sophisticated stuff that you might never have thought of trying.
Lots of great commands are listed at the Vim Tips Wiki.
It's also good to run the vimtutor when learning these commands
alias vi nedit :)
all humor aside..
for vi WHEN NOT using nedit..
i (switch to insert mode)
a (append = move to end of line and switch to insert mode)
esc (exit insert mode)
dd delete a line
x delete a character
:wq (save and quit)
/ start a search
n find Next
? search backwards..
yy (yank) copy a line to the buffer
pp (paste) paste it here
r (replace a character)
<N> <command> this is a neat - but aggravating feature that lets you type digits and then a command so
5dd will delete 5 lines
but at this point you might as well
- man vi and refresh your memory
While there are LOTS more, I switched from Vi to nedit several years ago, which I find has more features I can use on a regular basis more easily. Tabbed editing, incremental search bar, column select, copy and paste. sort selected lines, search and destroy within selection, whole doc or all open docs..
tear-off drop down menus..
and it supports syntax highlighting for all the languages I use.. (with pattern files I've used a long time over the years. VIM many now be equivalent, but It has to introduce a feature that Nedit doesn't and an easy way to migrate my pattern files before I switch again.
I like the Vim 5.6 Reference Guide, by Bram Moolenaar and Oleg Raisky.
You can directly print it in booklet form, easy to read, I always have it laying around.
It's a tad old, but what are 8 years in Vi's lifespan ?
:set ignorecase smartcase
Makes searching case-insensitive, unless your search includes a capital letter. Not the most indispensable perhaps, but I find myself setting this option any time I'm editing in a new place. It's in any vimrc file I own.
:%!xxd
View the contents of a buffer in hexadecimal. To revert:
:%!xxd -r
My biggest tip: ctrl+q saves the day when you accidentally hit ctrl+s to save the file you are working on
I have this in my vimrc
set number
set relativenumber
This gives me a line numbering system which makes j, k keys really productive.
I use vi very lightly, and I only use the following commands:
a - switch to insert mode (after the cursor)
esc - return to command mode
:wq - save and quit
:q - quit (no save, only without modification)
:q! - force quit (no save, also with modification)
x - delete one character (in command mode)
dd - delete the whole line (in command mode)
I know there are many many more, but those are enough to get you by.
One of my favourite commands is %G which takes to directly to the end of a file. Especially useful in log-files.
How to switch between modes (i to enter insert mode (one of many ways), esc to exit insert mode, colon for command mode) and how to save and exit. (:wq)
Another useful command is to search something: /
e.g. /Mon will search (and in case of vim highlight) any occurences of Mon in your file.
As a couple of other people have already mentioned, vimtutor is the way to go. It will teach you everything you need to know in vim. The one piece of general advice I would give you is to stay out of insert mode as much as possible. There is enormous power in the other modes, it just takes a little bit of practice to get used to it.
i - insert mode (escape to exit)
dd - delete line
shift-y - 'Yank' (copy) line
p - 'Put' (paste) line(s)
shift-v - Visual mode used to select text (tryin 'yanking' this text and 'putting' it somewhere.
ctrl-w n - create new window (you can open a file or start new file here)
ctrl-w v - split existing window vertically
ctrl-n (in insert mode) - autocomplete (if supported)
:! to run a shell command, usually with standard in as the file or a selection (shift-V)
Useful plugins to look at:
* Buffer Explorer - use \be to view files in the buffer (and select to re-open)
NB vi is not vim! vim is rapidly turning into the emacs of the new century. nvi is probably the closest thing to the original vi. Here's a nice hint: "xp" will exchange two characters (try it).
replace 'foo' with 'bar' everywhere in the file
:%s/foo/bar/gc
The real power is in the searching. Here are the essential commands:
/Steve will find the first instance of "Steve" in the text.
n will find the next "Steve" in the text.
:%s//Stephen/g will replace all those instances of "Steve" you just searched for with "Stephen".
Not to promote myself, but I wrote a blog post on this subject. It focuses on the critical parts of Vim for a beginner.
My favorites:
% find matching bracket/brace
* and # next/previous match
gg top of page
G end of the page
<Ctrl-v> Change to visual mode and select column
<Ctrl-a> increase current number by 1
<Ctrl-x> decrease current number by 1
Running macros

Resources