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Why isn't there a logical XOR operator?

Of course one can get the effect with appropriate use of existing
operators, but a ^^ operator would make for nice symmetry (as well as
useful to me in something I'm working on). Am I the only one who
would find it useful?

Christopher Benson-Manica | I *should* know what I'm talking about - if I
ataru(at)cybers pace.org | don't, I need to know. Flames welcome.
Nov 14 '05
80 35190
Larry Doolittle wrote:
stelios xanthakis wrote:
A *logical* expression a ^^ b ^^ c ^^ d ^^ e
is beyond the understanding of the average human being.

Maybe "average human beings" shouldn't try to write or
maintain non-trivial C programs.

That expression is true if an odd number of a, b, c, d,
and e are true.

- Larry

#define _(x) !!(x)

now your expression, including ensuring logical values, becomes:

_(a) ^ _b) ^ _(c) ^ _(d) ^ _(d) ^ _(e)
a ^ b ^ c ^ d ^ e

when the values are preknown to be logical, i.e. 0 or 1. In that
case you can also use:

(a + b + c + d + e) & 1

(and I believe the single _ to be a valid identifier)

Chuck F (cb********@yah oo.com) (cb********@wor ldnet.att.net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home .att.net> USE worldnet address!
Nov 14 '05 #81

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