open Errors (** Signature for a module describing an identifier. We often need identifiers (for definitions, variables, etc.) and in order to make sure we don't mix them, we use a generative functor (see [IdGen]). *) module type Id = sig type id type generator (** Id generator - simply a counter *) type 'a vector val zero : id val fresh : generator -> id * generator val to_string : id -> string val empty_vector : 'a vector val vector_to_list : 'a vector -> 'a list val vector_of_list : 'a list -> 'a vector val length : 'a vector -> int val nth : 'a vector -> id -> 'a val nth_opt : 'a vector -> id -> 'a option val update_nth : 'a vector -> id -> 'a -> 'a vector val iter : ('a -> unit) -> 'a vector -> unit val map : ('a -> 'b) -> 'a vector -> 'b vector module Set : Set.S with type elt = id val set_to_string : Set.t -> string module Map : Map.S with type key = id val id_of_json : Yojson.Basic.t -> (id, string) result val vector_of_json : (Yojson.Basic.t -> ('a, string) result) -> Yojson.Basic.t -> ('a vector, string) result end (** Generative functor for identifiers. See [Id]. *) module IdGen () : Id = struct (* TODO: use Z.t *) type id = int type generator = id type 'a vector = 'a list let zero = 0 let incr x = (* Identifiers should never overflow (because max_int is a really big * value - but we really want to make sure we detect overflows if * they happen *) if x == max_int then raise (Errors.IntegerOverflow ()) else x + 1 let fresh gen = (gen, incr gen) let to_string = string_of_int let empty_vector = [] let vector_to_list v = v let vector_of_list v = v let length v = List.length v let nth v id = List.nth v id let nth_opt v id = List.nth_opt v id let rec update_nth vec id v = match (vec, id) with | [], _ -> failwith "Unreachable" | _ :: vec', 0 -> v :: vec' | x :: vec', _ -> x :: update_nth vec' (id - 1) v let iter = List.iter let map = List.map module Set = Set.Make (struct type t = id let compare = compare end) module Map = Map.Make (struct type t = id let compare = compare end) let set_to_string ids = let ids = Set.fold (fun id ids -> to_string id :: ids) ids [] in "{" ^ String.concat ", " (List.rev ids) ^ "}" let id_of_json js = (* TODO: check boundaries ? *) match js with | `Int i -> Ok i | _ -> Error ("id_of_json: failed on " ^ Yojson.Basic.show js) let vector_of_json a_of_json js = OfJsonBasic.combine_error_msgs js "vector_of_json" (OfJsonBasic.list_of_json a_of_json js) end type name = string list [@@deriving yojson] (** A name such as: `std::collections::vector` (which would be represented as [["std"; "collections"; "vector"]]) *)