Newsgroups: comp.std.c++
Path: utzoo!censor!geac!alias!news
From: Reid Ellis <rae@utcs.toronto.edu>
Subject: Re: Responses to ~const 1.6: Alternatives to ~const
Message-ID: <1991Mar1.094159.40@alias.uucp>
Sender: Reid Ellis <rae%alias@csri.toronto.edu>
Reply-To: Reid Ellis <rae@utcs.toronto.edu>
Organization: Alias Research, Inc. Toronto ON Canada
References: <NGO.91Feb19113232@tammy.harvard.edu>
Distribution: comp
Date: Fri, 1 Mar 91 09:41:59 GMT

Tom Ngo <ngo@tammy.harvard.edu> writes:
>.. you have to set up two classes which are <identical in all
>respects except that in one, all members are non-const, and in the
>other, all data members are const except the ones that you want to
>behave as if they were ~const.
...
>Are there any other alternatives?

How about this?

struct foo {
	foo();
	int method() const;
	int sometimes() const;
	int nonconst();
private:
	foo & fRef;
};

foo::foo() : fRef(*this) {}

Then, if say "sometimes()" needs to do a non-const thing, it can
simply say "fRef.nonconst()".

I guess this is esentially casting the const away, but the compiler
won't make a peep about it.

					Reid
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