This is the revision history for $a xor $b in <discord.gg:#412831877242683403>

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10446 $a xor $b is [fact $a]
Don't use $a or $b as variable names. Not even in examples. They are not normal variables and will not behave like normal variables. The only place they are cromulent is in a sort or List::Util block. Please see https://metacpan.org/pod/Perl::Critic::Policy::Freenode::DollarAB ; consider using $x, $y instead. | https://perldoc.pl/variables/$a		 pink_mist <*:##NULL>