An update of https://gist.github.com/masak/158336 , four years later

passwords.pl

sub only($rx) { /^ <$rx>+ $/ } 
sub letters-with($n, $rx) { my $n1 = $n+1; /^ [<alpha>*] ** $n1 % <$rx> $/ }
sub letters-with-any($rx) { /^ [<alpha>*]+ % <$rx> $/ }
sub alnums-with($n, $rx) { my $n1 = $n+1; /^ [<alnum>*] ** $n1 % <$rx> $/ }

my @types =
    'total                ' => *,
    '  alphanumerics-only ' => only(/<alnum>/),
    '    digits-only      ' => only(/\d/),
    '    letters-only     ' => only(/<alpha>/),
    '    letters&u-score  ' => letters-with-any(/'_'/),
    '    letters&digits   ' => letters-with-any(/\d/),
    '      letters&1digit ' => letters-with(1, /\d/),
    '      letters&2digits' => letters-with(2, /\d/),
    '      letters&3digits' => letters-with(3, /\d/),
    '      letters&4digits' => letters-with(4, /\d/),
    '      letters&5digits' => letters-with(5, /\d/),
    '      letters&6digits' => letters-with(6, /\d/),
    '  with non-alnums    ' => only(/<-alnum>/),
    '    1 non-alnum      ' => alnums-with(1, /<-alnum>/),
    '    2 non-alnums     ' => alnums-with(2, /<-alnum>/),
    '    3 non-alnums     ' => alnums-with(3, /<-alnum>/),
;

my @pwds = lines.map: { /^\d+\s+(\S+)/ or next; ~$0 };

for @types».kv -> $type, $matcher {
    my $occ = +@pwds.grep($matcher);
    printf "%-22s%3d  (%6.2f%%)\n", $type, $occ, $occ/@pwds*100;
}