Re: eval-case and toplevel prohibitions

[Ludovic Courtès]

Hello!

Andy Wingo <address@hidden> writes:

> So I was thinking: why do we have this fetish for prohibiting certain
> forms in a non-toplevel context? I am of a mind to replace eval-case
> with eval-when, which is actually more expressive, as it allows us to
> discriminate the different phases in non-toplevel contexts as well.

Could it be because `eval-case' expressions can evaluate to nothing,
which can be confusing in non-top-level contexts, e.g.,

  (define (nothing)
    (let ((foo (eval-case ((never-true) 'foo))))
      foo))

Actually, this yields #<unspecified> in Guile-VM and #f in `master'.
The definition of `toplevel-env?' in there in quite sloppy...

Thanks,
Ludo'.