Tabs in vim
Options Explanation
expandtab: a boolean value controls whether the real input is a tab character (\t) or the specified number of spaces.
'expandtab' 'et' 'noexpandtab' 'noet'
'expandtab' 'et' boolean (default off)
local to buffer
In Insert mode: Use the appropriate number of spaces to insert a
<Tab>. Spaces are used in indents with the '>' and '<' commands and
when 'autoindent' is on. To insert a real tab when 'expandtab' is
on, use CTRL-V<Tab>. See also :retab and ins-expandtab.
tabstop: number of spaces a tab visually counts for. Defaults to 8. It does not affect how many spaces/tabs will be inserted directly.
shiftwidth: number of columns to use when indenting, such as >>. When zero it falls back to tabstop value.
'shiftwidth' 'sw'
'shiftwidth' 'sw' number (default 8)
local to buffer
Number of spaces to use for each step of (auto)indent. Used for
'cindent', >>, <<, etc.
When zero the 'ts' value will be used. Use the shiftwidth()
function to get the effective shiftwidth value.
softtabstop: a integet defaults to 0. It defined how many columns moved when <tab> is pressed or <BS>-ed. When expandtab is true, it always uses space, otherwise it uses a mix of spaces and tabs. A negative value makes it fall back to the value shiftwidth.
For example:
when :set tabstop=4 softtabstop=8 noexpandtab, pressing <tab> once will move you 8 columns right, inserting 2 tabs. When there are 14 spaces in the buffer, pressing <BS> will remove 6 (move you 6 columns left to the nearest tabstop), and next press will remove the 8 left.
when set tabstop=8 softtabstop=4 noexpandtab, pressing <tab> once will move you 4 columns right, it does so by inserting 4 spaces. Pressing <tab> again will move you 4 columns right again, but the former 8 spaces is now replaced by one tab (\t). Now press <BS> once, you are moved 4 columns left, the tab is now removed (because tabstop=8) and there are 4 spaces left.
when set tabstop=4 softtabstop=0 noexpandtab, the softtabstop feature is disabled. Each time you press <tab>, you insert a tab and moves to the next tabstop.
'softtabstop' 'sts'
'softtabstop' 'sts' number (default 0)
local to buffer
Number of spaces that a <Tab> counts for while performing editing
operations, like inserting a <Tab> or using <BS>. It "feels" like
<Tab>s are being inserted, while in fact a mix of spaces and <Tab>s is
used. This is useful to keep the 'ts' setting at its standard value
of 8, while being able to edit like it is set to 'sts'. However,
commands like "x" still work on the actual characters.
When 'sts' is zero, this feature is off.
When 'sts' is negative, the value of 'shiftwidth' is used.
See also ins-expandtab. When 'expandtab' is not set, the number of
spaces is minimized by using <Tab>s.
The 'L' flag in 'cpoptions' changes how tabs are used when 'list' is
set.
The value of 'softtabstop' will be ignored if 'varsofttabstop' is set
to anything other than an empty string.
smarttab: a boolean value controls whether a tab length is shiftwidth or tabstop/softtabstop.
'smarttab' 'sta' 'nosmarttab' 'nosta'
'smarttab' 'sta' boolean (default on)
global
When on, a <Tab> in front of a line inserts blanks according to
'shiftwidth'. 'tabstop' or 'softtabstop' is used in other places. A
<BS> will delete a 'shiftwidth' worth of space at the start of the
line.
When off, a <Tab> always inserts blanks according to 'tabstop' or
'softtabstop'. 'shiftwidth' is only used for shifting text left or
right shift-left-right.
What gets inserted (a <Tab> or spaces) depends on the 'expandtab'
option. Also see ins-expandtab. When 'expandtab' is not set, the
number of spaces is minimized by using <Tab>s.
autoindent: boolean value, defaults on. When starting a newline, copy indent from current line.
'autoindent' 'ai' 'noautoindent' 'noai'
'autoindent' 'ai' boolean (default on)
local to buffer
Copy indent from current line when starting a new line (typing <CR>
in Insert mode or when using the "o" or "O" command). If you do not
type anything on the new line except <BS> or CTRL-D and then type
<Esc>, CTRL-O or <CR>, the indent is deleted again. Moving the cursor
to another line has the same effect, unless the 'I' flag is included
in 'cpoptions'.
When autoindent is on, formatting (with the "gq" command or when you
reach 'textwidth' in Insert mode) uses the indentation of the first
line.
When 'smartindent' or 'cindent' is on the indent is changed in
a different way.
{small difference from Vi: After the indent is deleted when typing
<Esc> or <CR>, the cursor position when moving up or down is after the
deleted indent; Vi puts the cursor somewhere in the deleted indent}.
smartindent: boolean value controls the behavior when dealing with {, }, or cinwords. Defaults to off.
'smartindent' 'si' 'nosmartindent' 'nosi'
'smartindent' 'si' boolean (default off)
local to buffer
Do smart autoindenting when starting a new line. Works for C-like
programs, but can also be used for other languages. 'cindent' does something like this, works better in most cases, but is more strict,
see C-indenting. When 'cindent' is on or 'indentexpr' is set,
setting 'si' has no effect. 'indentexpr' is a more advanced alternative.
Normally 'autoindent' should also be on when using 'smartindent'.
An indent is automatically inserted: - After a line ending in "{".
- After a line starting with a keyword from 'cinwords'.
- Before a line starting with "}" (only with the "O" command).
When typing '}' as the first character in a new line, that line is
given the same indent as the matching "{".
When typing '#' as the first character in a new line, the indent for
that line is removed, the '#' is put in the first column. The indent is restored for the next line. If you don't want this, use this mapping: ":inoremap # X^H#", where ^H is entered with CTRL-V CTRL-H.
When using the ">>" command, lines starting with '#' are not shifted
right.
Best practices
There are four main ways to use tabs in Vim:
1. Always keep 'tabstop' at 8, set 'softtabstop' and 'shiftwidth' to 4
(or 3 or whatever you prefer) and use 'noexpandtab'. Then Vim
will use a mix of tabs and spaces, but typing <Tab> and <BS> will
behave like a tab appears every 4 (or 3) characters.
2. Set 'tabstop' and 'shiftwidth' to whatever you prefer and use
'expandtab'. This way you will always insert spaces. The
formatting will never be messed up when 'tabstop' is changed.
3. Set 'tabstop' and 'shiftwidth' to whatever you prefer and use a
modeline to set these values when editing the file again. Only
works when using Vim to edit the file.
4. Always set 'tabstop' and 'shiftwidth' to the same value, and
'noexpandtab'. This should then work (for initial indents only)
for any tabstop setting that people use. It might be nice to have
tabs after the first non-blank inserted as spaces if you do this
though. Otherwise aligned comments will be wrong when 'tabstop' is
changed.
How to set individual tab options for different filetypes?
in vim, use autocmd.
autocmd BufEnter *.py :setlocal tabstop=4 shiftwidth=4 expandtab
in neovim, use ftplugin.
-- nvim/ftplugin/python.lua
vim.bo.tabstop = 4
vim.bo.shiftwidth = 4
vim.bo.expandtab = true
vim.bo.softtabstop = 4
in nixvim, use files sub-modules. ref
programs.nixvim = {
enable = true;
files.foo = {
path = "ftplugin/python.lua";
opts.expandtab = true;
};
};
and as in submodules path defaults to name, so this is also fine:
programs.nixvim = {
enable = true;
files."ftplugin/python.lua" = {
opts.expandtab = true;
};
};
#Neovim #Nixvim #vim