From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Knutsson <ricknu-0@student.ltu.se>
Date: Thu, 15 Mar 2007 14:08:17 +0000
Subject: [KJ] [RFC] A need for a "yesno"-function?
Message-Id: <45F95351.60308@student.ltu.se>
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To: kernel-janitors@vger.kernel.org

Hi

Was just checking up the 'sparse' when I saw something like "abc"[value] 
and thought: what about the (statement) ? "yes" : "no" I have seen in 
the kernel.

Ran:
grep -Enr "\?.*y.*\:.*n" *
and to my surprise, it was not so false-positive-prone and there are 
many who does it. (Piping it to "grep yes" resulted in 153 hits) So I 
thought, if we could standardize this and eliminate some jmp-commands 
while doing it (the compiler should make the functions below inline), it 
might be interesting.

char yesno_chr(const bool value)
{
	return "ny"[value];
}

char *yesno_str(const bool value)
{
	return &"no\0yes"[3 * value];
}


(there may be better names for them)
I believe this should be slightly faster. I wrote two programs (one for 
each approach) and used 'time' while running them, and in a loop of 
1000,000 I found the above to be slightly faster, but the variations 
between runs were larger.
So maybe it is as well to write: return value ? "yes" : "no"; but i 
think there is a need for this kind of functions at least.

Thoughts?

Richard Knutsson

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