sidef/scripts/RosettaCode/primality_by_trial_division.sf

#!/usr/bin/ruby

#
## https://rosettacode.org/wiki/Primality_by_trial_division
#

func is_prime(a) {
  given (a) {
    when (2)                   { true  }
    case (a <= 1 || a.is_even) { false }
    default                    { range(3, a.sqrt) -> any { .divides(a) } -> not }
  }
}

25.times { |i|
    is_prime(i) && say i;
}