Due to the way that the keyboard input is handled internally, this unfortunately isn't generally possible today, even in GVIM. Some key combinations, like Ctrl + non-alphabetic cannot be mapped, and Ctrl + letter vs. Ctrl + Shift + letter cannot be distinguished. (Unless your terminal sends a distinct termcap code for it, which most don't.) In insert or command-line mode, try typing the key combination. If nothing happens / is inserted, you cannot use that key combination. This also applies to <Tab>
/ <C-I>
, <CR>
/ <C-M>
/ <Esc>
/ <C-[>
etc. (Only exception is <BS>
/ <C-H>
.) This is a known pain point, and the subject of various discussions on vim_dev and the #vim IRC channel.
Some people (foremost Paul LeoNerd Evans) want to fix that (even for console Vim in terminals that support this), and have floated various proposals, cp. http://groups.google.com/group/vim_dev/browse_thread/thread/626e83fa4588b32a/bfbcb22f37a8a1f8
But as of today, no patches or volunteers have yet come forward, though many have expressed a desire to have this in a future Vim 8 major release.
1had this keycode mapping/recognition problem been resolved in Vim 8, as of now (year 2017)? I find I can still reproduce Jon's example on my Vim 8.0 – llinfeng – 2017-07-24T13:06:57.933
@llinfeng: No, unfortunately not. Bram is currently working on integrating a terminal into Vim; this seems to use a library produced by Paul Evans, so maybe this will eventually lead to an improvement on the handled keys, too. (But this is pure speculation at this time.) – Ingo Karkat – 2017-07-25T07:17:11.037