sha1 hash

sha1.p6

subset Sha1 of Str where *.chars == 40 and m:i/<[A..Z 0..9]>/;

class Sha1H does Associative {
  has $!sha1;
  has %!h{Sha1(Str)};
  method AT-KEY($_) { %!h{ .lc } };
  method ASSIGN-KEY($_, $v) { %!h{ .lc } = $v }
}

class Sha1Str is Str {
  method Sha1 {
    (('a'..'z').pick(10) X (^10).pick(10)).roll(20).flat.join;
  }
}

my %h is Sha1H;
my $sha1 = Sha1Str.new; # '64B0F6C3681E428CCE2EB830B05F27B3D7ED643';
say $sha1.Sha1;
%h{$sha1} = 'a';
say %h{$sha1};
%h<a> = 'b';