runtime/defaults.vim

" The default vimrc file.
"
" Maintainer:	The Vim Project <https://github.com/vim/vim>
" Last Change:	2024 Nov 14
" Former Maintainer:	Bram Moolenaar <Bram@vim.org>
"
" This is loaded if no vimrc file was found.
" Except when Vim is run with "-u NONE" or "-C".
" Individual settings can be reverted with ":set option&".
" Other commands can be reverted as mentioned below.

" When started as "evim", evim.vim will already have done these settings.
if v:progname =~? "evim"
  finish
endif

" Bail out if something that ran earlier, e.g. a system wide vimrc, does not
" want Vim to use these default values.
if exists('skip_defaults_vim')
  finish
endif

" Use Vim settings, rather than Vi settings (much better!).
" This must be first, because it changes other options as a side effect.
" Avoid side effects when it was already reset.
if &compatible
  set nocompatible
endif

" When the +eval feature is missing, the set command above will be skipped.
" Use a trick to reset compatible only when the +eval feature is missing.
silent! while 0
  set nocompatible
silent! endwhile

" Allow backspacing over everything in insert mode.
set backspace=indent,eol,start

set history=200		" keep 200 lines of command line history
set ruler		" show the cursor position all the time
set showcmd		" display incomplete commands

set ttimeout		" time out for key codes
set ttimeoutlen=100	" wait up to 100ms after Esc for special key

" Show @@@ in the last line if it is truncated.
set display=truncate

" Show a few lines of context around the cursor.  Note that this makes the
" text scroll if you mouse-click near the start or end of the window.
set scrolloff=5

" Do incremental searching when it's possible to timeout.
if has('reltime')
  set incsearch
endif

" Do not recognize octal numbers for Ctrl-A and Ctrl-X, most users find it
" confusing.
set nrformats-=octal

" For Win32 GUI: remove 't' flag from 'guioptions': no tearoff menu entries.
if has('win32')
  set guioptions-=t
endif

" Don't use Q for Ex mode, use it for formatting.  Except for Select mode.
" Revert with ":unmap Q".
map Q gq
sunmap Q

" CTRL-U in insert mode deletes a lot.  Use CTRL-G u to first break undo,
" so that you can undo CTRL-U after inserting a line break.
" Revert with ":iunmap <C-U>".
inoremap <C-U> <C-G>u<C-U>

" In many terminal emulators the mouse works just fine.  By enabling it you
" can position the cursor, Visually select and scroll with the mouse.
" Only xterm can grab the mouse events when using the shift key, for other
" terminals use ":", select text and press Esc.
if has('mouse')
  if &term =~ 'xterm'
    set mouse=a
  else
    set mouse=nvi
  endif
endif

" Only do this part when Vim was compiled with the +eval feature.
if 1

  " Enable file type detection.
  " Use the default filetype settings, so that mail gets 'tw' set to 72,
  " 'cindent' is on in C files, etc.
  " Also load indent files, to automatically do language-dependent indenting.
  " Revert with ":filetype off".
  filetype plugin indent on

  " Put these in an autocmd group, so that you can revert them with:
  " ":autocmd! vimStartup"
  augroup vimStartup
    autocmd!

    " When editing a file, always jump to the last known cursor position.
    " Don't do it when the position is invalid, when inside an event handler
    " (happens when dropping a file on gvim), for a commit or rebase message
    " (likely a different one than last time), and when using xxd(1) to filter
    " and edit binary files (it transforms input files back and forth, causing
    " them to have dual nature, so to speak) or when running the new tutor
    autocmd BufReadPost *
      \ let line = line("'\"")
      \ | if line >= 1 && line <= line("$") && &filetype !~# 'commit'
      \      && index(['xxd', 'gitrebase', 'tutor'], &filetype) == -1
      \ |   execute "normal! g`\""
      \ | endif

    " Set the default background for putty to dark. Putty usually sets the
    " $TERM to xterm and by default it starts with a dark background which
    " makes syntax highlighting often hard to read with bg=light
    " undo this using:  ":au! vimStartup TermResponse"
    autocmd TermResponse * if v:termresponse == "\e[>0;136;0c" | set bg=dark | endif
  augroup END

  " Quite a few people accidentally type "q:" instead of ":q" and get confused
  " by the command line window.  Give a hint about how to get out.
  " If you don't like this you can put this in your vimrc:
  " ":autocmd! vimHints"
  augroup vimHints
    au!
    autocmd CmdwinEnter *
	  \ echohl Todo |
	  \ echo gettext('You discovered the command-line window! You can close it with ":q".') |
	  \ echohl None
  augroup END

endif

" Switch syntax highlighting on when the terminal has colors or when using the
" GUI (which always has colors).
if &t_Co > 2 || has("gui_running")
  " Revert with ":syntax off".
  syntax on

  " I like highlighting strings inside C comments.
  " Revert with ":unlet c_comment_strings".
  let c_comment_strings=1
endif

" Convenient command to see the difference between the current buffer and the
" file it was loaded from, thus the changes you made.
" Only define it when not defined already.
" Revert with: ":delcommand DiffOrig".
if !exists(":DiffOrig")
  command DiffOrig vert new | set bt=nofile | r ++edit # | 0d_ | diffthis
		  \ | wincmd p | diffthis
endif

if has('langmap') && exists('+langremap')
  " Prevent that the langmap option applies to characters that result from a
  " mapping.  If set (default), this may break plugins (but it's backward
  " compatible).
  set nolangremap
endif