On Wed, Apr 13, 2005 at 07:15:48AM -0400, John Macdonald wrote:
> On Tuesday 12 April 2005 23:46, Patrick R. Michaud wrote:
> > No, I'm afraid I haven't messed up my math. Integer-xor is &infix:<+^> .
> > Array-of-bits-xor is &infix:<~^> . I'm specifically talking about
> > &infix:<xor>, which "Perl 6 and Parrot Essentials" says (p. 36):
>
> Time for me to see the optometrist.
>
> I could have sworn that your examples were returning 0 and 2, but
> that's definitely a 6 up there. We're violently in agreement. The
> "boolean" form of xor is associative about the true/false meaning
> of what it returns, but non-associative about what actual value is
> returned for true.
>
> I apologize. You were not mixed up or messed up.
Thanks, I can see it was an honest error. I've done the same. :-)
For clarity in future discussions, I'd suggest that we bear in
mind that perl 6 makes a distinction between "boolean xor" and
"logical xor". "Boolean xor" is officially &infix:<?^>, and
returns a true/false value based on the truth/falsity of its
arguments. "Logical xor" is &infix:<^^> (tight) or
&infix:<xor> (loose), and returns false if both arguments are true,
false if both arguments are false, or its non-false argument.
For completeness, from S03:
and or xor not
boolean &infix:<?&> &infix:<?|> &infix:<?^> &prefix:<!>
integer &infix:<+&> &infix:<+|> &infix:<+^> &prefix:<+^>
string &infix:<~&> &infix:<~|> &infix:<~^> &prefix:<~^>
logical tight &infix:<&&> &infix:<||> &infix:<^^>
logical loose &infix:<and> &infix:<or> &infix:<xor> &prefix:<not>
Pm
