let or_op (phi : clause) (psi : clause) =
fun one_dpm -> unit_set (
fun (r, h) ->
- in let truth_value' = (
+ let truth_value' = (
truths (phi one_dpm) (r, h) <> [] ||
truths (bind_set (negate_op phi one_dpm) psi) (r, h) <> []
) in (truth_value', r, h))
let if_op (phi : clause) (psi : clause) : clause =
fun one_dpm -> unit_set (
fun (r, h) ->
- in let truth_value' = List.for_all (fun one_dpm ->
+ let truth_value' = List.for_all (fun one_dpm ->
let (truth_value, _, _) = one_dpm (r, h)
in truth_value = false || truths (psi one_dpm) (r, h) <> []
) (phi one_dpm)
type clause = bool dpm -> bool dpm set;;
+* More:
+
(* this generalizes the getx function from hint 4 *)
let get (var : char) : entity dpm =
fun (r, h) ->
else bind_dpm entity1_dpm (fun e1 -> bind_dpm entity2_dpm (fun e2 -> unit_dpm (f e1 e2)))
in fun one_dpm -> unit_set (bind_dpm one_dpm eliminator);;
-
-
let new_peg_and_assign (var_to_bind : char) (d : entity) : bool -> bool dpm =
fun truth_value ->
fun (r, h) ->
(* include negate_op, and_op, or_op, and if_op as above *)
+* More:
+
(* some handy utilities *)
let (>>=) = bind_set;;
let getx = get 'x';;