Want Vim to automatically do things to new or existing files? Autocmd to the rescue! Here I will demo a very simple example that I use for when I create/edit bash/python files.
I created the directory .vim in the root of my home directory and then created the "header" files that I wanted.
$ cat .vim/python_header :insert #!/usr/bin/python3 ################################################################################ #### #### Filename: #### #### Purpose: #### #### Created on: #### #### Author: #### #### Last Modified: #### ################################################################################ .
The first line must be :insert and the last line must be a period '.'
I then added the following lines to the .vimrc file in the root of my home directory.
" Python file header
autocmd bufnewfile *.py so /home/cdstealer/.vim/python_header
autocmd bufnewfile *.py exe "4" "g/Filename:.*/s//Filename:\t\t\t" .expand("%")
autocmd bufnewfile *.py exe "6" "g/Purpose:.*/s//Purpose:\t\t\t"
autocmd bufnewfile *.py exe "8" "g/Created on:.*/s//Created on:\t\t" .strftime("%c")
autocmd bufnewfile *.py exe "10" "g/Author:.*/s//Author:\t\t\t" .$USER
autocmd Bufwritepre,filewritepre *.py execute "normal ma"
autocmd BufWritePre,FileWritePre *.py exe "12" "g/Last Modified:.*/s/Last Modified:.*/Last Modified:\t\t" .strftime("%c") . " by " . $USER
autocmd bufwritepost,filewritepost *.py execute "normal `a"
Note: Lines that start with a double quote are treated as comments.
The official docs can be found here.
Explanation:
The first autocmd line specifies the file. Due to the :insert, this is then inserted into the new file.
bufnewfile: means take the following action on a new file.
Bufwritepre,filewritepre: means update the file only if editing not creating.
Lines 2, 3, 4 & 5 are basic search and replace for the header file being inserted.
The number in quotes after the exe is the line number to work on. You can set this to a range instead of being specific. The syntax is:
"<starting line number>," . <end line number> .
Once saved, you can test straight away by starting a new file:
$ vi python_test.py 1 #!/usr/bin/python3 2 ################################################################################ 3 #### 4 #### Filename: python_test.py 5 #### 6 #### Purpose: 7 #### 8 #### Created on: Fri 30 Dec 2016 19:18:58 GMT 9 #### 10 #### Author: cdstealer 11 #### 12 #### Last Modified: 13 #### 14 ################################################################################
Save the file and then re-open, make a small change and the "Last Modified" line will now contain a date stamp.
1 #!/usr/bin/python3 2 ################################################################################ 3 #### 4 #### Filename: python_test.py 5 #### 6 #### Purpose: To test 7 #### 8 #### Created on: Fri 30 Dec 2016 19:18:58 GMT 9 #### 10 #### Author: cdstealer 11 #### 12 #### Last Modified: Fri 30 Dec 2016 19:20:38 GMT by cdstealer 13 #### 14 ################################################################################
Very very useful ;)