WITCH hat: Revision 1
-- Used when something "wears many hats"
Operators containing this character
~^ and +^ and ?^ An exclusive or bitwise operation (or an invert, if only one argument)
When used inside regexes
Variable names starting with hats inside a pointy block or sub are placeholder variables
As an adverb
Method names starting with hats are metaclass methods
Hyper operator and meta operator restrictions
Old, deprecated, or other language uses
^ was bitwise exclusive or in Perl 5. In Perl 6 that's ~^, +^, or ?^ for bitwise, and ^^ in logic.