indent an existing unindented file as per some indentation commands supposedly written for autoindenting new files

Question

I have created some indentation commands like set shiftwidth=4, set autoindent and so on.... in my .vimrc file in my home folder and I'm able to get new files auto-indented happily.

What I want to know is if there is some script or way to indent existing file as per a particular indentation (say indentation script written by me (.vimrc) or default indentation standard for a particular extension that vim is intelligent enough to do.... )

The existing file has no consistent indentation used. Hope the question is clear.

Answer 1

I don't find that I'm able to get away with a single ts and sw setting. The proper values depend on the file type.

Therefore, I use the following functions in my .vimrc:

function SpaceTabs(spaces)
    exe "set sw=" . a:spaces
    exe "set ts=" . a:spaces
    exe "set expandtab"
    exe "set smarttab"
    exe "retab"
endfunction

function TabTabs(stops)
    exe "set ts=" . a:stops
    exe "set sw=" . a:stops
    exe "set noexpandtab"
    exe "set nosmarttab"
endfunction

Then below that, I have the following to enforce my local choices:

au BufEnter *.dbx call SpaceTabs(2)
au BufEnter *.docbook call SpaceTabs(2)
au BufEnter *.html call SpaceTabs(2)
au BufEnter *.md call SpaceTabs(4)
au BufEnter *.pal call TabTabs(8)
au BufEnter *.xml call SpaceTabs(2)
au BufEnter *.xsl call SpaceTabs(2)

I've edited that down to common file extensions, except for *.pal (the common PDP-8 assembly language form) which I've left as an example of one of that rare cases where I really do want hard tabs.

And then below that, my defaults, which keeps the file type specific listing above as short as possible:

au BufLeave * call SpaceTabs(4)
call SpaceTabs(4)

You may then ask, why do I need the *.md rule? It's in case I run into a Markdown file not produced under these same rules, because I always want to retab them when I open them. I'm careful adding such things; I don't do it on purpose for C and C++ files, because that's just as likely to wreck the formatting as fix the formatting of a free-form language, unlike with Markdown.

If you run across a file that doesn't get "fixed" the way you like this way and you can't be bothered to add one of these BufEnter rules, you can say

 :call SpaceTabs(4)

With Vim's command completion, this is quick to type.