Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!mailrus!accuvax.nwu.edu!Krulwich
From: Krulwich@eecs.nwu.edu (Bruce Krulwich)
Newsgroups: comp.lang.lisp
Subject: Re: Common Lisp's SETF feature
Message-ID: <991@accuvax.nwu.edu>
Date: 4 Aug 89 01:35:53 GMT
References: <2360@husc6.harvard.edu>
Sender: news@accuvax.nwu.edu
Reply-To: Krulwich@eecs.nwu.edu (Bruce Krulwich)
Organization: Institute for the Learning Sciences, Northwestern University, Evanston, IL 60201
Lines: 19
In-reply-to: whitney@endor.harvard.edu (Glen Whitney)

In article <2360@husc6.harvard.edu>, whitney@endor (Glen Whitney) writes:
> Suppose I have a variable, FRED, whose value is a place
> descriptor for SETF, like (get 'joe 'eye-color), and I
> would like to SETF into the place described by FRED's
> value. Is there any nice way of doing this? I couldn't
> figure one out. Any help would be appreciated. 

I almost break out in hives to say this, but one way would be:

    (eval `(setf ,fred ,<value descriptor>))

but I think that unless you're doing a debugging system or something like that
there must be a way around having to use the interpreter like this.  Are you
sure you haven't made some (bad) design choice that has forced you to do
horrible stuff like this??


Bruce Krulwich
Institute for the Learning Sciences