🚀 go-pugleaf

Shankar Unni (shankar@engr.sgi.com) wrote:
: Robert Risack (rtrisack@faui01.informatik.uni-erlangen.de) wrote:

: > I'm wondering why there isn't a logical XOR operator (eg. ^^)
: > though there is a bitwise one (ie. ^).

: Oh, please!

: We've been through exactly this specific battle about once every semester
: (hint) on comp.{lang,std}.c ...  Anyone care to summarize the arguments?

While I agree that it is a common and basically pointless question, I
can't believe that a message which is nothing but a flame made it past
moderation.

[ Point well taken. My mistake. -sdc ]

The answer is that there is no such thing as a short-circuiting
exclusive-or.  With && and ||, the second argument may not be
evaluated.  With the proposed ^^, both arguments would have to be
evaluated.  There is already a perfectly good logical exlusive-or
operator for bools: operator !=.  If you want the logical exclusive-or
of non-booleans (a dubious proposition IMHO), you have to go for !a !=
!b.  Such a strange computation deserves slightly strange notation.

dougm@rice.edu (Doug Moore)
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