The following Perl 6 implementation probably isn't the fastest you can find, but it certainly one of the shortest: 

sub is_prime (Int $n) {
    $n % all(2 .. sqrt($n)+1);
}

[download]

Credit: Autrijus in the Apocalypse Now talk.

In reply to Re: Simple primality testing by gaal
in thread Simple primality testing by ambrus

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