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Date: Tue, 01 Nov 2011 05:34:40 -0500
From: pete <pfiland@mindspring.com>
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Subject: Re: the loop control
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.c:12435

Ike Naar wrote:
 
> In the simpler example that you showed (only one sweep
> across the point array), one can make a tradeoff between two
> desirable objectives:
> a) keeping the parameters constant
> b) minimizing the number of local variables
> 
> I think a) vs. b) is a honest tradeoff,
> and not a dumb vs. smart question.

My preference is to alter the value of parameters 
at every given oportunity.

void strcpy(char *s1, const char *s2)
{
    while ((*s1++ = *s2++) != '\0') {
        ;
    }
}

If it turns out that I need the original value
of a parameter throughout the code,
then my preference is to do that by initializing
a const qualified local variable with the original value
of the parameter.

That's very easy to do, 
even as an alteration to code which was originally written
without preserving the parameter value.

char *strcpy(char *s1, const char *s2)
{
    char *const p1 = s1;

    while ((*s1++ = *s2++) != '\0') {
        ;
    }
    return p1;
}

-- 
pete