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From: faustus@fir.Berkeley.EDU (Wayne Christopher)
Newsgroups: comp.lang.lisp
Subject: Re: Using Packages With CLOS
Message-ID: <26581@pasteur.Berkeley.EDU>
Date: 30 Jul 90 23:03:18 GMT
Sender: news@pasteur.Berkeley.EDU
Reply-To: faustus@fir.Berkeley.EDU (Wayne Christopher)
Organization: University of California at Berkeley
Lines: 24
X-Local-Date: 30 Jul 90 16:03:18 PDT

The problem with using packages and CLOS is that unless you are careful
you can get lots of name conflicts.  Say I have two rather general
classes, foo and bar, each in its own package.  Each has a slot called
"name", and, following the convention used in the CLOS book, I have
defined and exported accessors called "name" for both.  When I try to
use both classes in one package, I get a symbol conflict.  There are a
few ways to avoid this:

	1. Make foo import the symbol name from bar, or vice versa --
	   not too modular.
	
	2. Use keywords for accessor functions.  Pretty ugly.

	3. Don't use-package either foo or bar, and use foo:name or
	   bar:name when necessary.
	
	4. Call the accessor functions foo-name and bar-name, as with
	   structures.

I've been using (4), but it was sort of an annoying surprise to
realize that converting my program to use packages would require
me to change all my accessor function names.

	Wayne