(* This file is free software, part of containers. See file "license" for more details. *) include Bool let if_then f x = if x then Some (f ()) else None let if_then_else f g x = if x then f () else g () let of_int x : t = x <> 0 type 'a printer = Format.formatter -> 'a -> unit let pp = Format.pp_print_bool