node f(x:int) returns (y,z:int)
let
  automaton
    state A
      do y = x;
  z = 4;
      until y = 2 then B
    state B
      do y = x;
    automaton
      state C
        do z = y
        until z = 3 then D
      state D
        do z = x
        until z = 4 then A
    end
      until y = 2 then A
  end;
tel