specific system_out (MosML lacks structure Posix);
dummy implementation of Posix.ProcEnv.getpid;
structure Nat =
struct
datatype nat = Suc of nat | Zero_nat;
val one_nat : nat = Suc Zero_nat;
fun nat_case f1 f2 Zero_nat = f1
| nat_case f1 f2 (Suc nat) = f2 nat;
fun plus_nat (Suc m) n = plus_nat m (Suc n)
| plus_nat Zero_nat n = n;
fun times_nat (Suc m) n = plus_nat n (times_nat m n)
| times_nat Zero_nat n = Zero_nat;
end; (*struct Nat*)
structure Codegen =
struct
fun fac n =
(case n of Nat.Zero_nat => Nat.one_nat
| Nat.Suc m => Nat.times_nat n (fac m));
end; (*struct Codegen*)