-*- mode:org; mode: read-only -*- vim:foldmethod=marker:nomodifiable:tw=2048  

This document can be read as "folded document" in Vim or Neovim or 
in GNU Emacs (org-mode)

If this text file is viewed in a browser, encoding should be set to utf-8

Vim:
zo opens a fold
zc closes

The Vim text text editor -- tips and tricks (Volker Kiefel 2023-10-23)

* Reopen files at the last cursor position (save cursor position) {{{

Insert a small vim script code into initialization file. The code may be found
in the help system with

:help restore-cursor

or

:help last-position-jump
}}}

* Change end of line codes: DOS/UNIX {{{

:set fileformat=dos
:set fileformat=unix
}}}

* Search and replace with confirmation {{{
  :34,45s/old/new/gc
}}}

* Folds {{{

set foldmethod=manual

{Visual}zf  
   creates a fold

zd
   deletes the fold under the cursor

zE
   eliminates all folds in the window

zo
   opens the fold

zc
   closes the fold

For use of LaTeX files three curly braces are not optimal, as three curly
braces often occur in normal text/code. You may therefore define an
alternative (pair of) foldmarker(s). An example for a modeline for a LaTeX
file.

  % vim:foldmethod=marker foldmarker=--->,<--- 


}}}

* Navigate in a text {{{
  
** Local variables in C sourcecode
  jump from use of a variable to its local declaration:
  gd

** Coordinate movements in two windows
  in window 1:
  :set scrollbind
  in window 2,
  :set scrollbind

 This command is further specified:
    ver         Bind vertical scrolling for 'scrollbind' windows
    hor         Bind horizontal scrolling for 'scrollbind' windows
    jump        Applies to the offset between two windows for vertical
 example:
  :set scrollopt=ver,hor

}}}

* Navigate in LaTeX projects with ctags {{{

The following was published by daniel kullmann:
https://stackoverflow.com/questions/8119405/create-tags-file-for-latex-for-labels-and-bib-items

see `latex-tips.txt' write:

--langdef=tex2
--langmap=tex2:.tex
--regex-tex2=/\\label[ \t]*\*?\{[ \t]*([^}]*)\}/\1/l,label/

--langdef=bib
--langmap=bib:.bib
--regex-bib=/^@[A-Za-z]+\{([^,]*)/\1/b,bib/

into $HOME/.ctags

ctags *.tex *.bib works now as I want it. Exuberant ctags must be used.

Documentation: http://ctags.sourceforge.net/EXTENDING.html

}}}

* Use diff {{{

Start diff mode from VIM; fist file in actual window, call second file with
:diffsplit {filename}

Transfer differences for range from the other window to the current window
:[range]diffget
Transfer differences for range from the current window to the other window
:[range]diffput

}}}

* Using eVim (easy VIM) {{{

   gvim -y

** execute one command, return to Insert mode
   ctrl-o (described in help files i_CTRL-O)
   ctrl-l (switch to normal mode)
}}}

* iskeyword  {{{
  
  set isk+=58

}}}

* Modification of text files by external files {{{
  
  If changes of a text file by an external program are made vim shall read the
  file again automatically with

  :set autoread

}}}

* Processing files with <tab>s {{{
  :set tabstop=n
  (Number of spaces that a <Tab> in the file counts for)

  to remove tabs:
  :set expandtab
  :retab!

  to replace tabs by approprate counts of spaces:
  :set noexpandtab
  :retab!
  

  show tab and end of line characters:
  :set list

  (see documentation:)
  :help 'list'
}}}

* Visual  {{{

gv 
  Start Visual mode with the same area as the previous area and the same mode.
  In Visual mode the current and the previous Visual area are exchanged.


g CTRL-G
  shows the number of characters selected in visual mode

  (documentation: help g_CTRL-G, :help v_g_CTRL-G)

}}}

* Menus in console mode (Vim) {{{
  Description see console-menus 
}}}

* Line/word wrapping {{{
  set wrap 
  
  wraps lines exactly at end of window
  
  set wrap 
  set lbr [linebreak]
  
  wraps lines at whitespaces between words, however this only affects display,
  no <EOL>s are inserted.

  {Visual}J
  Join highlighted lines, remove the indent, insert spaces

  {Visual}gJ
  Join the highlighted lines, do not insert or remove spaces

}}}

* Distance between lines:  {{{
  set linespace=1

  engerer Abstand mit kleineren Ziffern 
}}}

* count words {{{
  g <CTRL-G>
  Works also in visual mode
}}}

* Problems with syntax highlighting {{{
  
  e. g. with TeX: force Vim to reanalyse
  current file from beginning
  :syntax sync fromstart


  a pleasant colorscheme for vim
  :colorscheme manxome
}}}
  
* Control maximum size of registers written to viminfo file {{{

  some configuration paramaters can be written into the viminfo string, an
  example:

  set viminfo='20,s1000,h

  this means that: 
  - marks are remembered for the last 20 edited files
  - maximum size of registers saved in Kbyte (1000 Kbyte)
  - Disables the effect of 'hlsearch' when loading the viminfo file

}}}

* Vim and the clipboard  {{{
  
  set clipboard=unnamed  

  Vim takes all text that should go in the unnamed register and puts it in the
  clipboard register

}}}

* Insert text from a register into the ex cmd line {{{

  The following command inserts text from the GUI clipboard
  
  Ctrl-R +

  cf :help i_Ctrl-R
 
}}}

* set options of gvim GUI {{{
  
  Add scrollbar at the bottom of the screen:
  guioptions+=b

  Define GUI font in gvim (Windows, example):
  set guifont=Liberation_Mono:h10

  Define GUI font in gvim (Linux, examples):
  set guifont=DejaVu\ Sans\ Mono\ 15
  set guifont=Liberation\ Mono\ 11

}}}

* set language for use of menu translation {{{
  
  if the language for the menus is set to a non-English language put
  :set langmenu=none
  before loading menus.

}}}

* Install German dictionary (Vim v7, win32, Linux) {{{

Get German Dictionary from 
  http://lingucomponent.openoffice.org/spell_dic.html

unzip de_DE.zip. Install with 
  :mkspell \vim\vim70\spell\de de_DE

Under Linux:
  Create ~/.vim/spell
  unzip de_DE.zip in the current directiry
  start vim and run
  :mkspell ~/.vim/spell/de de_DE

this generates de.latin1.spl.

to turn on spelling:

  :set spell
  :set spelllang=de


...

Experience with Windows 10:

Vim Spell-Checker: create German spl-file

Uncompress "dict-de_de-igerman98_2011-06-21.oxt" with unzip

This creates subdirectory de_DE_igerman98/ with the
files "de_DE_igerman98.aff" and "de_DE_igerman98.dic"

The file "de.latin1.spl" is created with the command

:mkspell c:\vim\vim74\spell\de de_DE_igerman98/de_DE_igerman98

}}}

* Problem with automatic installation of German dictionary from the web {{{

Find the server with '/vim/runtime/spell', then enter

  :let g:spellfile_URL = 'https://ftp.pl.vim.org/pub/vim/runtime/spell'

If the server exists, automatic download will begin.

Source:

https://vi.stackexchange.com/questions/5651/how-can-i-make-vim-download-spell-files

A list of mirrors is found at: https://www.vim.org/mirrors.php
Then add '/runtime/spell' to the url. So a valid repository for spelling
files may be found.

(2022-10-23)

}}}

* Apply an external program or shell command ("filter") to marked text {{{

Mark Text, apply external command with "!"

  :!fmt -w 77

reformats block of text with 77 columns

}}}

* External commands: compile LaTeX documents with ltxshell, enter filename at command line {{{

External commands are entered at the command line:

:!command

In order to enter the filename at the command line enter the contents of
register `%':

:ctrl-r %

The `ltxshell' command can be started with

:!ltxshell ctrl-r %

Then remove the trailing `.tex'. Explanation: The vim-register `%' contains
the name of the current file.

Documentation on ctrl-r: 

:help i_ctrl-r

}}}

* Print/list lines and line number with specified content {{{

Example:

:g/^\\begin{[pr]sli/nu

prints all lines and line numbers containing

\begin{psli

or

\begin{rsli

}}}

* Show editor line numbers {{{

:set number
:set nu
:set nonumber

or even better

:set relativenumber
:set rnu
:set norelativenumber

}}}

* Force vim on Windows to show encoding with :set fenc {{{

On Windows systems the following line should be entered as one of the last 
lines to _vimrc:

  :set enc=utf-8

Probably this forces vim to use utf-8 encoding internally and then 

  :set fenc

prints the correct encoding, either latin1 or utf-8

}}}

* Edit files with "exotic" encoding {{{  

To save a file with cp850 encoding:

  :set fileencoding=cp850

To open a file with cp850 encoding:

  :edit ++encoding=cp850 filename
  :edit ++enc=cp850 filename

To open a file with cp850 encoding from the command line

  vim -c ":edit ++enc=cp850 filename"

To get information of encoding of currently opened file:

  :set fileencoding

Help on encoding:
   
   :help ++enc
   :help charset
   :help encoding-values

}}}

* Enter characters by number, characters by numeric value {{{
  
  CTRL-V nnn   (decimal)
  CTRL-V Onnn  (octal)
  CTRL-V Xnn   (hexadecimal)

  see :help i_CTRL-V_digit

  Enter Unicode Characters: CTRL-V u 1F00 (results in small alpha with spritus lenis)

}}}
  
* Using the Help system {{{ 

:helpgrep keyword

show the list with items found:

:cwindow

show the next/previous item found:

:cn
:cp

show the introduction screen/opening screen/about text

:intro

}}}

* Toggle Cursor shape in Vim (Terminal) {{{ 

   togglecursor.vim:

   https://github.com/jszakmeister/vim-togglecursor/blob/master/plugin/togglecursor.vim

   https://www.vim.org/scripts/script.php?script_id=4403

}}}

* Highlight current line {{{

  :set cursorline
}}}

* Turn off/on highlighting of corresponding parentheses {{{

  :NoMatchParen
  :DoMatchParen

}}}

* Information on vim (for website) {{{

https://groups.google.com/forum/#!forum/vim_use

}}}

* Commands for help files {{{

ctags and structure of tags files (tags-file-format)
:help tagsrch

}}}

* Neovim, nvim {{{

nvim "diagnostics"
:checkhealth
(only nvim, not vim)

access to clipboard: install xclip or xsel, details see:
:help clipboard

(only nvim, not vim)

}}}

* Build, compile neovim, nvim install in HOME (Linux) {{{

from https://github.com/neovim/neovim/wiki/Building-Neovim
and https://github.com/neovim/neovim/wiki/Installing-Neovim#install-from-source

For Unix-like systems this installs Neovim to /usr/local, while for Windows
to C:\Program Files. Note, however, that this can complicate uninstallation.
The following example avoids this by isolating an installation under
$HOME/neovim:

   make CMAKE_EXTRA_FLAGS="-DCMAKE_INSTALL_PREFIX=$HOME/neovim"
   make install

tested on 2023-08-06

}}}

* Show whitespace characters in nvim {{{

  :set list listchars=tab:>\ ,trail:-,eol:$

or

  :set list listchars=tab:>\ ,space:·,trail:-,eol:$
  
(showing also spaces as "·") for documentation in nvim:

  :help listchars

source: https://vi.stackexchange.com/questions/11887/show-newline-characters-in-neovim

The middle dot (·) has the decimal numeric value: 183 

}}}

* Neovim: set indentation depth in C functions {{{

  :set cindent shiftwidth=2 

This also affects the (undesired) indentation within environments in LaTeX
documents. For documentation:

  :helpgrep :set cindent shiftwidth

}}}