Path: utzoo!utgpu!news-server.csri.toronto.edu!torsqnt!tmsoft!masnet!rose!phil.calvin
From: phil.calvin@rose.uucp (PHIL CALVIN)
Newsgroups: comp.lang.c++
Distribution: world
Subject:  MEMBER ACCESS
Message-ID: <97edfa6b92f028446f60@rose.uucp>
Date: Wed, 29 May 91 20:20:00 EST
Organization: Rose Media, ON, CANADA
Lines: 47


 A language feature I'd like to see...

 A class has certain data members, for efficiency reasons, I would like
to grant the USER read-only access.

 EX:

 class COORD
   {
 public:
   // Don't modify just read..
   int x,y;
   ...
   };

 Obviously, the comment does little more than _encourage_ the user to
modify the value.  My proposal is to have language support for this
concept:

EX:

class COORD
   {
const public:
   int x,y;     // Not an lvalue, compile will flag as errors.

const protected:
   int a,b;     // Same thing, derived class may read, not write
   ...
   }

A couple of points:
   1. Obviously const private makes no sense
   2. class members and friends always have write access (unless, of
      course the object is const)

Any remarks/flames etc??  Has this facility been discussed and
rejected??

If so, would someone summarize reasons and email me??

Thanks..
..Phil
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