Damian Conway writes
about the power of infinite sequences in Perl 6.
filtered (with a .grep) to keep only the ones that are prime.
And, of course, Perl 6 already has a prime number tester: the built-in
&is-prime function. The sequence of primes never changes, so we can
declare it as a constant:
constant p = [ (1..∞).grep( &is-prime ) ];
Now we need to extract just the strong and weak primes.