module PROPAGATE (TYPES) is

process PART [PROPAGATE: any] (ID: PID) is
   alt
      i; PROPAGATE (ID, "X")
   []
      i
   end alt
end process

process MAIN [PROPAGATE: any] is
   loop
      par
         PART [...] (1 of PID)
      ||
         PART [...] (2 of PID)
      ||
         PART [...] (3 of PID)
      ||
         PART [...] (4 of PID)
      end par
   end loop
end process

end module