:- type incrementer_states  ---> a ; halt.
:- type incrementer_symbols ---> b ; '1'.

:- func incrementer_config = config(incrementer_states, incrementer_symbols).
incrementer_config = config(a,           % the initial state
                            set([halt]), % the set of halting states
                            b).          % the blank symbol

:- pred incrementer(incrementer_states::in,
                    incrementer_symbols::in,
                    incrementer_symbols::out,
                    action::out,
                    incrementer_states::out) is semidet.
incrementer(a, '1', '1', right, a).
incrementer(a, b,   '1', stay,  halt).

TapeOut = turing(incrementer_config, incrementer, [1, 1, 1]).