module STOCKS (DATAP, CHANNELS) is

!update "2021-b"  -- use standard operator priority

-------------------------------------------------------------------------------

process Stock_a [Deposit: DepositChan, Withdraw: WithdrawChan]
                (M_a: Amount, prd: Product, in var amt: Amount) is
   var newamt: Amount in
         loop
            alt
               Deposit (prd, ?newamt) where
                  newamt <= M_a and newamt > 0 of Amount;
               amt := amt + newamt
            []
               Withdraw (prd, ?newamt) where newamt <= M_a and newamt <= amt;
               amt := amt - newamt
            end alt
         end loop
   end var
end process

-------------------------------------------------------------------------------

process Stock_p0 [Deposit: DepositChan, Withdraw: WithdrawChan] (M_a:Amount) is
   Stock_a [Deposit, Withdraw] (M_a, 0 of Product, 0 of Amount)
end process

-------------------------------------------------------------------------------

process Stock_p1 [Deposit: DepositChan, Withdraw: WithdrawChan] (M_a:Amount) is
  Stock_a [Deposit, Withdraw] (M_a, 1 of Product, 0 of Amount)
end process

-------------------------------------------------------------------------------

end module