Re: problem with (display . [not expire]) with git emacs

[Dan Christensen <jdc@uwo.ca>]

On Feb  1, 2024, Eric Abrahamsen <eric@ericabrahamsen.net> wrote:

> I just tried it out, and actually got a popup buffer with the "Malformed
> function" error you mentioned in your first message.

Glad to hear that it's not just me.  I wish I could get that pop-up as
well, or that I could make emacs enter the debugger when this happens.
It would be easier to figure out that way.  Any idea why we would have
different behaviour here?

> Looks like the culprit is effectively this:
>
> (gnus-byte-compile
>   `(lambda ()
>     ,(cdr (assoc 'expire gnus-summary-display-cache))))

I think it's like that but with '(not expire).  When the predicate
is a single symbol, it looks like this code skips byte compilation:

    (if (and (= (length func) 1)
	     (symbolp (car func)))
	(car func)
      (gnus-byte-compile `(lambda () ,func)))))

(But I'm not sure how (display . expire) results in a *list* of length
one.)  Can you confirm that you don't get the error with (display . expire)?

Do you think the issue is that we're trying to byte-compile an already
compiled function?  Do you think the commit I referenced introduces a
bug, or that it reveals an existing bug in Gnus?  Do you suggest that
I post to an emacs devel list, or can we fix it here?

Dan