Another way of testing for primes is to use the prime regex. (For small numbers at least, it can exceed the recursion limit pretty quickly for larger numbers.)

use strict;
use warnings;

sub prime{
    (1 x shift) !~ /^1?$|^(11+?)\1+$/;
}

for (1..1000){
    print "$_\n" if prime $_;
}

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In reply to Re: Primes. Again. by thundergnat
in thread Primes. Again. by Andrew_Levenson

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