val list_known_developments: unit -> (string * string ) list
(* cleans the development, forgetting about it *)
val destroy_development: development -> unit
val list_known_developments: unit -> (string * string ) list
(* cleans the development, forgetting about it *)
val destroy_development: development -> unit
(* initiale internal data structures *)
val initialize : unit -> unit
(* gives back the root *)
(* initiale internal data structures *)
val initialize : unit -> unit
(* gives back the root *)