Binding toggle comment to <C-/>

Question

I installed NERDCommenter plugin and its default bindings unfortunately conflict with my own. For instance I use <Leader>-c and <Leader>-v to emulate CTRL-c and CTRL-v. And since IDEs usually use CTRL-/ to toggle comments I'd like to preserve this behavior.

I tried the following in my vimrc:

let g:NERDCommenterToggle = "<C-/>"

But when reloading the vimrc the old mapping <Leader>c<Space> is still in effect; the <C-/> mapping has no effect.

Is there a way to cancel all the default bindings introduced by NERDCommenter and bind only g:NERDCommenterToggle to C-/?

Answer 1

I'm just going by the help doc in github but it appears that 'NERDCreateDefaultMappings' does exactly what you want for the first part, ie. toggle on/off all mappings (bindings)...

If set to 0, none of the default mappings will be created.

Then you can manually bind to your heart's content. The help for NERDCommenterMappings has a bit of advice for that:

To change a mapping just map another key combo to the internal mapping. For example, to remap the |NERDCommenterComment| mapping to ",omg" you would put this line in your vimrc:

map ,omg <plug>NERDCommenterComment

Update: If you need more help let's look at how the default for NERDCommenterToggle is constructed. It should be clear now that we don't override like a normal variable (:let x = y) but rather we need to define a mapping. The relevant bits responsible for defining the default mapping...

call s:CreateMaps('nx', 'Toggle', 'Toggle', 'c<space>')

Signature of CreateMaps:

function! s:CreateMaps(modes, target, desc, combo)

Actual map definition where modes is split and iterated over such that mode has each value, n and x, in turn...

execute mode . 'map <leader>' . a:combo . ' ' . plug

Where plug is

let plug = '<plug>NERDCommenter' . a:target

So that translates to

nmap <leader>c<space> <plug>NERDCommenterToggle
xmap <leader>c<space> <plug>NERDCommenterToggle

So you want

nmap <C-/> <plug>NERDCommenterToggle
xmap <C-/> <plug>NERDCommenterToggle

You may not need the xmap version.

(Don't forget you need to set NERDCreateDefaultMappings to 0, too.)