| Binder of binder_kind * capture_variable * term (* kind, name, body *)
| Case of term * string option * term option * (case_pattern * term) list
(* what to match, inductive type, out type, <pattern,action> list *)
+ | Cast of term * term
| LetIn of capture_variable * term * term (* name, body, where *)
| LetRec of induction_kind * (capture_variable * term * int) list * term
(* (name, body, decreasing argument) list, where *)