bug#46636: 28.0.50; M-: (funcall #'or) doesn't throw an error

[Pip Cet]

On Fri, Feb 19, 2021 at 4:46 PM Philipp Stephani <p.stephani2@gmail.com> wrote:
> Am Fr., 19. Feb. 2021 um 15:03 Uhr schrieb Andreas Schwab
> <schwab@linux-m68k.org>:
> >
> > On Feb 19 2021, Pip Cet wrote:
> >
> > > Recipe starting from emacs -Q:
> > >
> > > M-: (funcall #'or) RET
> >
> > If you want authentic results, use ielm, not eval-expression.
>
> Ah, so the rewrite that macroexpand-all (in macroexp--expand-all)
> performs is the culprit here.

Yes, I think so.

> Maybe it should only rewrite if the
> first argument is indeed a function, or an autoload of a function?

I'm unconvinced it's worth it at all to rewrite funcalls or applys,
either in macroexp or in the byte compiler.

But if we have to, we have to make sure (apply #'or nil) and (funcall
#'or) are rejected somewhere (maybe as early as the #').