Newsgroups: comp.lang.clos
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From: dsr@mir.mitre.org (Douglas S. Rand)
Subject: Re: Specializing on &OPTIONAL parameters (was moooo!)
Message-ID: <1991Mar21.150203.4822@linus.mitre.org>
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Reply-To: dsr@mir.mitre.org (Douglas S. Rand)
Organization: The MITRE Corporation
References: <9103201709.AA20839@mingus.mitre.org> <31777@mimsy.umd.edu>
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Date: Thu, 21 Mar 1991 15:02:03 GMT

.... Lots of discussion about the topic

But,  there is nothing which prevents a programmer from creating a wrapper
function with optional parameters which calls the generic function.  So:

(defun wrapper-function (x y &optional (a (sexp)))
   (function x y a))

(defmethod function ((x sp1) (y sp2) (a sp3))
   body)

Why doesn't this totally satisfy the question?

Please don't tell me it's so people can specialized builtin functions to
CL because the committee has already disallowed this one (unless it's 
changed while I wasn't looking  :) ).

-- 
Douglas S. Rand 
Internet:   <dsrand@mitre.org>
Snail:	    MITRE, Burlington Road, Bedford, MA 
Disclaimer: MITRE might agree with me - then again...
Amateur Radio: KC1KJ