node count(c : int; r : bool) returns (res : int)
let
  res = 0 fby (if r then 0 else res + c);
tel

node byfour() returns (res : int)
let
  res = 0 fby (res + 4);
tel

node main() returns (c : int)
let
  c = count(byfour(), false);
tel