Path: utzoo!utgpu!water!watmath!clyde!att!ucbvax!bloom-beacon!CENTRO.SOAR.CS.CMU.EDU!Olin.Shivers
From: Olin.Shivers@CENTRO.SOAR.CS.CMU.EDU
Newsgroups: comp.lang.scheme
Subject: Non-upward-compatibility of Chez Scheme versions
Message-ID: <8807250215.AA15826@BLOOM-BEACON.MIT.EDU>
Date: 24 Jul 88 01:15:13 GMT
References: <1709@kalliope.rice.edu>
Sender: daemon@bloom-beacon.MIT.EDU
Organization: The Internet
Lines: 18


	   (let ([null? null?])
	     (define-macro! nil? (x)
	       `(,null? ,x))		; note comma before null?

I don't use the Scheme's you use, but I think I can see at least one
problem with this macro: functions are *not* defined in Scheme to be 
self-evaluating like, for example, integers are.
So instead of: 
    ,null?
you need:
    ',null?
As in:
	(let ((null? null?))
	  (define-macro! nil? (x)
	    `(',null ,x)))

    -Olin