Why can't I remap `gc` to `gc` and then `gv`?

Question

My vimrc already has the very useful mapping

vnoremap < <gv
vnoremap > >gv

I'm using the TComment plugin, and I'd like to also do something like

vmap gc gcgv

to re-highlight a visual selection after toggling gc.

But, as written, it just seems to prevent gc from working. vnoremap gives the same result.

Is there a way to do this with a simple mapping? Or should I write a function for it?

Answer 1

Indeed, you either defined a recursive mapping (vmap), or one that doesn't know that gc is supposed to comment something (vnoremap).

Solution: do what gc does (if you look at it with :verbose vmap gc), and add gv to it as you want:

:xmap gc <Plug>TComment_gcgv

It does look strange. Maybe that's why other plugins use a format like <Plug>(some_code) ?

Also note that (un)commenting may change the text "bounding box" and it won't necessarily correspond to the visual selection before the operation.