Newsgroups: comp.lang.c++
Path: utzoo!censor!geac!alias!barney!rae
From: Reid Ellis <rae@gpu.utcs.toronto.edu>
Subject: Re: calling main in ANSI C
Message-ID: <rae.660685914@barney>
Keywords: More on const.
Sender: Reid Ellis <rae%alias@csri.toronto.edu>
Reply-To: Reid Ellis <rae@gpu.utcs.toronto.edu>
Organization: Alias Research, Inc. Toronto ON Canada
References: <814@atcmpe.atcmp.nl> <535@taumet.com> <1990Dec4.055744.2191@cbnewsm.att.com>
Distribution: usa
Date:  8 Dec 90 19:51:54 GMT

Gregory P. Kochanski <gregk@cbnewsm.att.com> writes:
>void x(array& q)
>{
> q[0] = q[1];
>...
> q[2] = q[3];
>...
>}
>
>Now, on half of these calls, we're just 'reading' from the array,
>but we're still paying the heavy overhead for the non-const functions.
>Admittedly, they could just as well be written as
>q[0] = ((const array&)q)[1],

You could also write the following:

	void x(array& q)
	{
		const array &qc = q;
	
		q[0] = qc[1];
		...
		q[2] = qc[3];
		...
	}

But your 'array' class better not make any strange assumptions about
'clean' and 'dirty' arrays [i.e. the 'const' method should access the
actual data, not some sort of cached value, unless you're remembering
the array's current "dirtiness".

					Reid
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