Path: utzoo!attcan!uunet!dino!ux1.cso.uiuc.edu!ux1.cso.uiuc.edu!uxa.cso.uiuc.edu!jpd00964
From: jpd00964@uxa.cso.uiuc.edu
Newsgroups: comp.lang.lisp
Subject: functionp on the NeXT
Message-ID: <116000001@uxa.cso.uiuc.edu>
Date: 18 Nov 89 13:22:26 GMT
Lines: 25
Nf-ID: #N:uxa.cso.uiuc.edu:116000001:000:848
Nf-From: uxa.cso.uiuc.edu!jpd00964    Nov 17 12:40:00 1989


I an experienced programmer, but a lisp novice.  

The problem stems from the command functionp.  According to Winston & Horn
3rd Edition, functionp only returns T for a function.  Using it the problem
they give, however, it does not do what they say on the NeXT Franz Allegro
Common LISP system.

Looking into it some more, I find it returns T for functions, 'foo, nil, t, 
and anything bound to a symbol.
It returns false only for numbers and lists whose car is not lambda.

On an IBM PC using golden common lisp, I got nil for (functionp nil)

Which is right, and why?
Regardless, what good is functionp if it returns T for non functions?

I do not frequent this notesfile, so I would appreciate E-Mail instead of 
postings.  

Michael Rutman
jpd00964@uxa.cso.uiuc.edu
cc:dpd722@uxf.cso.uiuc.edu

The cc is for my friend, thanx to one and all.