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From: dkeisen@Gang-of-Four.Stanford.EDU (Dave Eisen)
Newsgroups: comp.lang.c
Subject: Re: The nonexistent operator (along = v. == lines)
Keywords: xor
Message-ID: <1991Apr3.203748.3226@neon.Stanford.EDU>
Date: 3 Apr 91 20:37:48 GMT
References: <156@revcan.UUCP> <157@revcan.UUCP>
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In article <157@revcan.UUCP> darren@revcan.UUCP (Darren Morbey) writes:
>What I did require was an operator, macro, or function that treated
>its operands as "zero" or "non-zero" as && and || do rather than
>the bitwise & | ^.  I also would like some guarantee that both
>operands were evaluated *once* *and* *only* *once* (O&OO).  Based
>on that, I do recognize that in

#define XOR(a,b)	(!!(a) ^ !!(b))

does what you want.




--
Dave Eisen                      
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