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From: mittle@blinn.watson.ibm.com (Josh Mittleman)
Newsgroups: comp.lang.c++
Subject: Re: beginners question
Message-ID: <1991Jun06.181745.26256@watson.ibm.com>
Date: 6 Jun 91 18:17:45 GMT
References: <1991Jun5.090228.27147@sinix.UUCP>
Sender: @watson.ibm.com
Organization: IBM T. J. Watson Research
Lines: 13

This is no small problem that you've encountered; several other recent
postings were other version of the same thing.  What you are looking for is
multiple polymorphism, i.e., the ability to have a virtual function depend
on the types of more than one of its arguments.  C++ does not provide this
feature.  There are way around it, but none of them are particualrly
satisfying.  A good discussion of the subject, particularly addressing the
domain of interest to you, can be found in "Generalized arithmetic in C++",
by Timothy A. Budd, which appears in the Feb. 91 issue of the Journal of
Object-Oriented Programming, pp.11-22.

===========================================================================
Josh Mittleman (mittle@watson.ibm.com or joshua@paul.rutgers.edu)
J2-C28 T.J. Watson Research Center, PO Box 704, Yorktown Heights, NY  10598