diff options
Diffstat (limited to 'example/turing/src/state.h')
| -rw-r--r-- | example/turing/src/state.h | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/example/turing/src/state.h b/example/turing/src/state.h index f5bd7f2..51fe347 100644 --- a/example/turing/src/state.h +++ b/example/turing/src/state.h @@ -9,12 +9,26 @@ namespace machine { namespace state { -struct field { +namespace field { using ID = tav::Size<0>; using READ = tav::Size<1>; using WRITE = tav::Size<2>; using NEXT = tav::Size<3>; using MOVE = tav::Size<4>; +} + +// (define (state_accessor state) +// (lambda (field) +// (nth field state))) +template <typename State> +struct state_accessor { + static_assert( + tav::IsPair<State>::value, + "machine state is invalid" + ); + + template <typename Field> + using get = tav::Nth<Field, State>; }; // (define (state_predicate id read) @@ -54,7 +68,9 @@ struct transition { typename State, typename Symbol > - using state = findState<State, Symbol, States>; + using state = state_accessor< + findState<State, Symbol, States> + >; }; } |