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From: jenny@ucbvax.ARPA (Kathryn Hargreaves)
Newsgroups: net.lang
Subject: Implementation of overloaded operators.
Message-ID: <10527@ucbvax.ARPA>
Date: Thu, 3-Oct-85 15:26:45 EDT
Article-I.D.: ucbvax.10527
Posted: Thu Oct  3 15:26:45 1985
Date-Received: Fri, 4-Oct-85 06:50:54 EDT
Organization: University of California at Berkeley
Lines: 16
Keywords: Orthogonality, abstraction, overloaded operators.

Algol 68 is the only language I know of that allows true programmer defined
operators, that is, to be able to say ``I want an postfix ! and here's the
definition.'' (At least I think Algol 68 does; I'm not particularly
well-versed in it.) Ada allows you to redefine existing operators, but not
create new ones. Two questions:
   1. Do any other languages allow such things?
   2. Have any readable papers been produced about implementing
programmer-defined operators? (Preferably the Algol 68 version, the Ada
version if that's all that's around.) By readable paper I mean something
other than a compiler listing. I know about ``Resolution of overloaded
operators in Ada'' (or some such title) in SIGPlan Notices a couple years
back.)
   Please reply to me, not the net.

Thanks,
jenny%ernie@ucbvax.arpa