In Operators§

See primary documentation in context for Negated relational operators.

The result of a relational operator returning Bool can be negated by prefixing with !. To avoid visual confusion with the !! operator, you may not modify any operator already beginning with !.

There are shortcuts for !== and !eq, namely != and ne.

my $a = True;
say so $a != True;    # OUTPUT: «False␤»

my $release = Date.new(:2015year, :12month, :24day);
my $today = Date.today;
say so $release !before $today;     # OUTPUT: «False␤»