Perl 6 - Subsets

subset Email of Pair where .key ~~ 'email' && .value ~~ /'@'/;

subset AccountID of Pair where .key ~~ 'accountid' && .value ~~ Int && .value.chars ~~ 12;

subset ID of Any where Email|AccountID;

multi sub foo(Str $email --> ID) { email => $email };

multi sub foo(Int $accountid --> ID) { accountid => $accountid };

my $id1 = foo('[email protected]');

say "id1 is Email? {$id1 ~~ Email}";

say "id1 is AccountID? {$id1 ~~ AccountID}";

my $id2 = foo(123123123123);

say "id2 is Email? {$id2 ~~ Email}";

say "id2 is AccountID? {$id2 ~~ AccountID}";