1 (* Subjective self-reports, apart from Evidence: what the trainee said, 2 not what the body did. *) 3 4 type level = Worse_than_usual | As_usual | Better_than_usual 5 6 let pp_level ppf = function 7 | Worse_than_usual -> Format.pp_print_string ppf "worse than usual" 8 | As_usual -> Format.pp_print_string ppf "as usual" 9 | Better_than_usual -> Format.pp_print_string ppf "better than usual" 10 11 type signal = Motivation of level | Difficulty of level 12 type t = { reported_at : Recovery.timestamp; signals : signal list } 13 type error = Duplicate_signal of signal 14 15 exception Invalid of error 16 17 let same_category left right = 18 match (left, right) with 19 | Motivation _, Motivation _ | Difficulty _, Difficulty _ -> true 20 | _ -> false 21 22 let make ~reported_at signals = 23 let rec validate seen = function 24 | [] -> { reported_at; signals } 25 | signal :: rest -> 26 if List.exists (same_category signal) seen then 27 raise (Invalid (Duplicate_signal signal)) 28 else validate (signal :: seen) rest 29 in 30 validate [] signals 31 32 let reported_at t = t.reported_at 33 let signals t = t.signals 34