🚀 go-pugleaf

In article <40sp1t$lbc@cd4680fs.rrze.uni-erlangen.de>,
Robert Risack <rtrisack@faui01.informatik.uni-erlangen.de> wrote:
>Hello.
>
>I'm wondering why there isn't a logical XOR operator (eg. ^^)
>though there is a bitwise one (ie. ^).
>
>The other bitwise operators ( & | and ~ ) have their logical
>aquivalent ( && || and ! ). And the XOR is IMHO not that uncommon.

There is a crucial difference; the evaluation of && and || can be
shortcut, while no such trick works for (the hypothetical) ^^, making
them quite different beasts.

&& and || are _not_ simply the boolean equivalents of & and |.  For
example, the following common code:

if (x && x->foo) { ... } 

is perfectly safe, while the bitwise version:

if (!!x & !! x->foo) { ... }

generates a null-pointer reference if x is zero.

-- 
Tim Hollebeek        |"What is love? 'tis not hereafter; Present mirth hath
PChem Grad Student   |present laughter; What's to come is still unsure: In
Princeton University |delay there lies no plenty; Then come kiss me, sweet and
---------------------|twenty, Youth's a stuff will not endure." -Twelfth Night

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