bug#33201: 26.1; Edebug doesn't work on closures with edebug-unwrap-results

[Eli Zaretskii]

> Date: Thu, 1 Nov 2018 10:00:56 +0000
> From: Alan Mackenzie <acm@muc.de>
> Cc: 33201@debbugs.gnu.org
> 
> > > This fix could probably be backported to the emacs-26 branch, but how
> > > important is it?  What were you actually trying to do when you uncovered
> > > this bug?
> 
> > I don't remember.  I have encountered this error multiple times before
> > and given up debugging something.  Since one generally runs into bugs
> > when doing work (that is not hacking on Emacs itself), it's helpful to
> > be able to debug with minimal obstruction, otherwise it becomes an
> > unjustifiable distraction from the main task.
> 
> OK, it sounds like it's a major problem.

It does?  Why?

> @Gemini: The patch below is a (small) portion of
> e09120d68694272ea5efbe13b16936b4382389d8 from 2018-06-19, the commit that
> introduced Backtrace Mode.  Can you see anything against applying this
> commit to the emacs-26 branch to fix this bug?

I can: it's quite complex, and even includes gratuitous refactoring of
'cond' as 'pcase'.