Kakoune: Support Alternative to Escape Key

[MasterOfTheTiger]

In Vim, if you do not have an escape key, you may use Ctrl+C to get out of insert mode. This is particularly useful in Termux for many Android keyboards which do not have an escape key.

[SolitudeSF]

Ctrl-[ works in every terminal

[Screwtapello]

You can already do something like:

map global insert <c-a> <esc>

...in your kakrc and then <c-a> will leave insert mode. Unfortunately it seems that <c-c> itself doesn't work, despite code to implement it, and I'm not sure why.

[alexherbo2]

@MasterOfTheTiger In [Termux], I like to type ‘__jj__’ to leave insert mode.

# Type <character><character> to leave insert mode.
# ['jj', 'kk']
hook global InsertChar '[jk]' %{ try %{
  execute-keys -draft "hH<a-k>%val(hook_param)%val(hook_param)<ret>d"
  execute-keys <esc>
}}

https://github.com/mawww/kakoune/wiki/Avoid-the-escape-key

[mawww]

In Kakoune, <c-c> is used to send SIGINT to the process group (similar to what it does by default in a shell). This is necessary so that we can kill some eventual subprocess we could be waiting on. In order to achieve that, <c-c> is treated specially, very early in input processing, as most other input is delayed until we get control back.

There is some code remaining that pretends to handle <c-c> as <esc>, but no <c-c> key stroke would ever get there, so it is not really useful. This should probably be cleaned up.

That means <c-c> is not available for mapping, and would not be a good candidate altenative for <esc>.

Other keys are easily mappable to <esc>, and I do not think we need to bless any choice with a default additional mapping.