Re: Using a macro with FOLD alters FOLD procedure!

[Neil Jerram]

Kevin Ryde wrote:
> I suppose it depends if a macro should be a first class object to be
> thrown around (or do I misunderstand?).
>
> I've been gradually converting srfi-1 procs to C, which has the side
> effect of checking the procs are actual procedures.  I suppose there
> must be plenty of ordinary application code passing procedures around
> in exactly the same way that's vulnerable to memoizing macros.
>
> (Could a memoized form check it's got the same macro as originally
> expanded, as a safety check?  Or do I misunderstand again?)

I think you understand fine - to the extent that I understand myself, 
anyway.

For reference, here's the first message in the 2002 thread that I 
mentioned: 
http://lists.gnu.org/archive/html/guile-devel/2002-01/msg00030.html

The key mail in this thread is probably Marius's one.  I have to say, 
though, that I don't yet understand how Marius's solution would solve 
the problem in the case of passing a macro to fold.

Regards,
        Neil