Re: "defined?" wants to be an `acro' (and not a macro)

Mikael Djurfeldt (mdj@nada.kth.se)
06 Nov 1996 10:14:59 +0100

Marius Vollmer <mvo@zagadka.ping.de> writes:

> I think the builtin macro/syntax "defined?" (defined in eval.c)
> should be an `acro' and not a macro as it currently is.

I agree that it would be silly if "defined?" was a macro, but it is a
memoizing macro, which means that next time we cross over the
"defined?" expression, we will only evaluate an immediate (#t or #f)
which will be very efficient.

> At least my experimental `tree-compiler' gets confused by it.

Hopefully, there exists an alternative solution.

Best regards,
/mdj