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NNTP-Posting-Date: Wed, 07 Jun 2017 14:54:26 -0500
From: Gareth Owen <gwowen@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: memscan() function or equivalent
References: <fc95db66-ccd5-4fbc-83bf-84cb17257d41@googlegroups.com> <20170607154705.f161b2807eb2b1a8dc12d389@gmail.com> <12fb0e96-0ac3-442d-8d04-baaef4234a85@googlegroups.com> <20170607164800.a6fba9d07170ec5d056d25a0@gmail.com> <878tl3g5jw.fsf@bsb.me.uk>
Date: Wed, 07 Jun 2017 20:54:25 +0100
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Xref: csiph.com comp.lang.c:111749

Ben Bacarisse <ben.usenet@bsb.me.uk> writes:

> What is the general view of writing things like
>
>   k += *s0 == c0;
>
> ?  I find it compact and natural with no extra cost, at least with
> modern compilers.

I don't madly care for it.  My brain has to work to spot which is the
assignment, and which is the comparison.

I'd probably write

if(*s0 == c0) k = k+1;


That's comprehensible to any programmer anywhere, and idiomatic in
almost every major imperative language - as well as directly expressing
what you want to do

Which of these is clearest:
           "If the characters match, increment the counter".
           "Increment the counter by one if the characters match,
            or zero if they don't"

They're logically equivalent identical, but one of those reads like I
think, and one of them reads like it was written by a Cylon.

I'd also consider

k += (*s0 == c0);

preferable to yours. I find it simply easier to parse mentally without
back-tracking.

Any compiler that produces different code for these should be taken out
and shot.