gistfile1.txt

sub cry_prime {
    for ^Inf {
        my @results = (
            await ^4 .map: {
                start {
                    sleep 1;
                    my $r = rand;
                    $r > .6 ?? $r !! False;
                }
            }
        ).grep: {$_};

        next unless @results;
        return @results[0];
    }
};

say cry_prime;
say now - INIT now;