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From: wlp@calmasd.Prime.COM (Walter Peterson)
Newsgroups: comp.lang.c
Subject: C history question
Keywords: C design, XOR
Message-ID: <575@calmasd.Prime.COM>
Date: 10 Sep 89 21:52:29 GMT
Organization: Prime - San Diego R&D (Object and Data Management Group)
Lines: 20


Perhaps someone can answer a question that has bugged me since I first
learned C almost 10 years ago.

C has bitwise operators for AND (&), OR (|) and XOR (^) and boolean 
operator for AND (&&) and OR (||), but not for XOR (^^). Why?
What happened to the boolean XOR operator ?  If && makes sense for the
boolean AND and || makes sense for the boolean OR, why doesn't ^^ make
sense for the boolean XOR ?

Most assemblers that I know have XOR as a single instruction so why
make people go to the trouble of writing something like
(a || b) && (!(a && b)) when a ^^ b is so much "cleaner".

Can anyone tell me why this was left out of the language ?  
Is there any chance that some future version of ANSI-C will have it ?

-- 
Walt Peterson.  Prime - San Diego R&D (Object and Data Management Group)
"The opinions expressed here are my own."