You could hide the guts in a function to make it more readable: 
sub single_true {
   my $count = 0;
   $_ && $count++ foreach @_;
   return $count == 1;
}

if (single_true($x, $y, $z)) {
   ...
}

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In reply to Re: One out of three ain't bad by ikegami
in thread One out of three ain't bad by saintmike

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