Path: utzoo!mnetor!uunet!husc6!mit-eddie!ll-xn!ames!oliveb!pyramid!prls!philabs!pwa-b!mmintl!franka
From: franka@mmintl.UUCP (Frank Adams)
Newsgroups: comp.lang.c++
Subject: Re: Why doesn't c++ allow overloading member operators?
Message-ID: <2783@mmintl.UUCP>
Date: 21 Mar 88 21:36:01 GMT
References: <11778@sri-spam.istc.sri.com> <8180005@eecs.nwu.edu>
Reply-To: franka@mmintl.UUCP (Frank Adams)
Organization: Ashton-Tate Corporation, East Hartford Development Center
Lines: 23

In article <8180005@eecs.nwu.edu> morrison@eecs.nwu.edu (Vance Morrison) writes:
>    The question is "why doen't c++ allow you to overload the "." operator.

Actually, the original poster was regarding ".member" as the operator, not
just the ".".

>    The real reason you probably want overloading is to allow "controled
>access" to instance variables.  What would meet this need without overloading
>the "." is for c++ to REDEFINE the "." operator for the class EXAMPLE so
>
>	example.member 		means 	example.member()

The problem is that there are, more or less, two operations associated with
members: access and update.  The above is useless if I want to want to use
statements like: "example.member = foo;".

(It is *not* sufficient to define the member() function as returning a
reference (such as "int &member()"), since in general, one wants to *do*
something for the access/assignment.)
-- 

Frank Adams                           ihnp4!philabs!pwa-b!mmintl!franka
Ashton-Tate          52 Oakland Ave North         E. Hartford, CT 06108