[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
DEFMAXing of ()
- To: ALAN at MIT-MC, GSB at MIT-MC
- Subject: DEFMAXing of ()
- From: JONL at MIT-MC (Jon L White)
- Date: Mon, 1 Dec 80 09:17:00 GMT
- Cc: (BUG LISP) at MIT-MC
- Original-date: 1 DEC 1980 0417-EST
Date: 1 December 1980 04:06-EST
From: Alan Bawden <ALAN at MIT-MC>
Just because a macro expanded into NIL, there is no reason to believe
that the calculation involved in computing that NIL was trivial.
It is a bug if the cache scheme doesn't work for NIL.
In this scheme, inherited from Chuck Rich's and integreated into PSZ's,
there was general agreement amongst those users that a () returned by
such a macro was the bug -- the output of such a macro should always
appear in an EVAL context, so returning (QUOTE () ) or (PROGN () )
should always be correct. I'm leary of having MACROMEMO do that
conversion (as GSB suggested), but will certainly fix it so that a given
cell won't get infinitely "cache"'d. Is there any comment on GSB's
proposal to have MACROMEMO do the fixup at runtime?