Encode_utils
val enc_req : ('a -> 'b) -> 'a -> 'b option
val enc_opt : ('a -> 'b) -> 'a option -> 'b option
val enc_repeat : ('a -> ('b * Imandra_prelude.String.t option) list) -> 'b -> 'a list -> ('b * Imandra_prelude.String.t option) list