VIM : Trouble mapping <c-/> and re-selecting visual selection?

Question

I am using a vim plugin called tComment

It allows me to comment a line by pressing gc or <c-_><c-_>

Also, it works on the shortcut <c-/><c-/> but the visual selection is lost.

So, I tried:

• To make it work on single <c-/>
• To retain the visual selection.

My attempts :

inoremap <c-/> gc
vnoremap <c-/> gc gv
nnoremap <c-/> gc

=========

imap <c-/> gc
vmap <c-/> gc gv
nmap <c-/> gc

=========

imap <c-/> gc$
vmap <c-/> gc$ gv
nmap <c-/> gc$

=========

inoremap <c-/> <c-_><c-_>
vnoremap <c-/> <c-_><c-_> gv
nnoremap <c-/> <c-_><c-_>

=========

imap <c-/> <c-_><c-_>
vmap <c-/> <c-_><c-_> gv
nmap <c-/> <c-_><c-_>

( Non of the above seems to work )

Note:

1. I have not done any other customizations from my side.
2. My attempts are listed above
3. Installing tComment on native vim (Ubuntu) lands you to my setup.

Answer 1

If I understand you correctly, you want to have one map (in i, n, & v-mode) that either comments the current line or the visual selection. This is what tcomment's <c-_><c-_> map does now (with the exception that you want to maintain the visual selection). In order to use <c-/> you have to set g:tcommentMapLeader1 = '' (or some other map, since <c-/> seems to be the same as <c-_> as echristopherson pointed out) in vimrc and then define your maps for <c-/>.

This should work (add these lines to .vimrc):

let g:tcommentMapLeader1 = ''
noremap <silent> <c-/> :TComment<cr>
vnoremap <silent> <c-/> :TCommentMaybeInline<cr>gv
inoremap <silent> <c-/> <c-o>:TComment<cr>

You might have to replace <c-/> with <c-_> to make this work. Since you reported that tcomment already worked when typing <c-/><c-/>, the <c-_> map should work.

Anyway, I'd also recommend to use the operator maps since those fit better the way vim works. I don't think using a single key is still a good idea though.

Answer 2

1. If you want to map keys to another mapping, you need to use :map, not :noremap.
2. For most plugins, this shouldn't be necessary; they usually provide either configuration variables or <Plug>PluginName... for that. Read :help g:tcommentMaps for instructions for this particular plugin, then place your overrides into your ~/.vimrc.