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From: jlg@cochiti.lanl.gov (Jim Giles)
Newsgroups: comp.lang.c
Subject: Re: The nonexistent operator (along = v. == lines)
Keywords: xor
Message-ID: <20206@lanl.gov>
Date: 4 Apr 91 17:23:29 GMT
References: <156@revcan.UUCP> <1991Apr3.184316.11559@dg-rtp.dg.com>
Sender: news@lanl.gov
Reply-To: jlg@cochiti.lanl.gov (Jim Giles)
Organization: Los Alamos National Laboratory
Lines: 15

> [...]
>   It can't be done.  The truth or falseness of a ^ expression
> cannot be determined without evaluating all the operands. [...]

What you are saying is obvious.  However, the original request
was for a _logical_ XOR instead of a _bit-wise_ XOR.  The fact
that you can't short-circuit XOR is irrelevant to that request.

This is one of the problems with confounding two distinct concepts
into one language feature - people soon begin to believe the two
concepts are inseparable.  In this case, short-circuiting and 
logical con/disjunction are distinct concepts that just happen
to be combined into single operators.

J. Giles