bug#51253: 28.0.60; Meta keys broken when viper is active

[Lars Ingebrigtsen]

John Cummings <john@rootabega.net> writes:

>> > https://debbugs.gnu.org/cgi/bugreport.cgi?bug=18182 was fixed in
>> > 5d522b430bd5ecfb8f082906cd634883dbb68f3e. This changed viper-ESC-key
>> > from <escape> to ESC, which resulted in a direct key binding of (27
>> > . 'viper-intercept-ESC-key) while in the viper vi/insert states.
>>
>> Maybe that commit should just be reverted?
>
> I've looked into this some more, and I think reverting it is the
> way that the entirety of the viper ESC-handling stack was designed
> to function.

I've now reverted it in emacs-28, and I'm reopening bug#18182.

> But if this does get reverted, and it turns out that allowing ESC to
> exit vi insert is still important, it doesn't seem like it would be
> too difficult to ignore direct ESC command bindings when looking up
> meta prefix bindings here:
> https://git.savannah.gnu.org/cgit/emacs.git/tree/src/keymap.c?id=f3aa648093a70c8ed15e764863a16fdf7126cdc4#n343
> I've been playing with it to help me get more familiar with it; maybe
> I'll have a proof of concept one day.

It would be nice to have it working, so if you can come up with a
solution, that'd be great.  (Post the solution to 18182, please.  :-)

-- 
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