From: ·······@dfki.uni-kl.de (Frank)
Subject: with-added-methods ?
Date: 6 Apr 1994 10:07:01 GMT
I would like to know, if there is any CL actually supporting the special form
WITH-ADDED-METHODS (CLtL2, pp 862-3). I've looked into Allegro 4.1, Lucid 4.1
and Symbolics 8.1.1, but neither seems tohave it. I would also appreciate any
suggestions how to implement a macro having the functionality of this form.
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Frank Steinle (·······@dfki.uni-kl.de)
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In article <··············@mmbbs.mn.org> ·····@mmbbs.mn.org (Frank) writes:
>I would like to know, if there is any CL actually supporting the special form
>WITH-ADDED-METHODS (CLtL2, pp 862-3). I've looked into Allegro 4.1, Lucid 4.1
>and Symbolics 8.1.1, but neither seems tohave it. I would also appreciate any
>suggestions how to implement a macro having the functionality of this form.
WITH-ADDED-METHODS was removed from the language by X3J13. I'm not sure
that it's possible to implement it portably using the primitives that CLOS
provides (you might be able to do it using the MOP, but it probably won't
be efficient).
Here's the proposal that contains the justification.
Issue: WITH-ADDED-METHODS
References: 88-002R p.2-90
Category: CHANGE
Edit history: 29-Apr-90, Version 1 by Moon
4-May-90, Version 2 by Moon (update discussion)
Problem description:
WITH-ADDED-METHODS has a strange definition that is hard to understand
and apparently is not what was intended by the person who originally
proposed the feature. No CLOS implementation is known that supports it.
This is Symbolics issue #17.
Proposal (WITH-ADDED-METHODS:DELETE):
Remove WITH-ADDED-METHODS from the language and remove that symbol from
the COMMON-LISP package.
Rationale:
Why add something new that no one uses or wants?
Current practice:
No CLOS implementation is known to support WITH-ADDED-METHODS.
Cost to Implementors:
Trivial.
Cost to Users:
None.
Cost of non-adoption:
We would either have to get the implementors to implement it or explain
why we put this thing in the language that everyone refuses to implement.
Performance impact:
None.
Benefits:
Smaller language.
Esthetics:
Smaller language.
Discussion:
Gregor Kiczales says he supports WITH-ADDED-METHODS:DELETE.
--
Barry Margolin
System Manager, Thinking Machines Corp.
······@think.com {uunet,harvard}!think!barmar