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+(************************************************************************)
+(* v * The Coq Proof Assistant / The Coq Development Team *)
+(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *)
+(* \VV/ **************************************************************)
+(* // * This file is distributed under the terms of the *)
+(* * GNU Lesser General Public License Version 2.1 *)
+(************************************************************************)
+
+(*i $Id: scheme.ml,v 1.9.2.1 2004/07/16 19:30:08 herbelin Exp $ i*)
+
+(*s Production of Scheme syntax. *)
+
+open Pp
+open Util
+open Names
+open Nameops
+open Libnames
+open Miniml
+open Mlutil
+open Table
+open Ocaml
+
+(*s Scheme renaming issues. *)
+
+let keywords =
+ List.fold_right (fun s -> Idset.add (id_of_string s))
+ [ "define"; "let"; "lambda"; "lambdas"; "match-case";
+ "apply"; "car"; "cdr";
+ "error"; "delay"; "force"; "_"; "__"]
+ Idset.empty
+
+let preamble _ _ (mldummy,_,_) =
+ (if mldummy then
+ str "(define __ (lambda (_) __))"
+ ++ fnl () ++ fnl()
+ else mt ())
+
+let paren = pp_par true
+
+let pp_abst st = function
+ | [] -> assert false
+ | [id] -> paren (str "lambda " ++ paren (pr_id id) ++ spc () ++ st)
+ | l -> paren
+ (str "lambdas " ++ paren (prlist_with_sep spc pr_id l) ++ spc () ++ st)
+
+(*s The pretty-printing functor. *)
+
+module Make = functor(P : Mlpp_param) -> struct
+
+let pp_global r = P.pp_global [initial_path] r
+let empty_env () = [], P.globals()
+
+(*s Pretty-printing of expressions. *)
+
+let rec pp_expr env args =
+ let apply st = pp_apply st true args in
+ function
+ | MLrel n ->
+ let id = get_db_name n env in apply (pr_id id)
+ | MLapp (f,args') ->
+ let stl = List.map (pp_expr env []) args' in
+ pp_expr env (stl @ args) f
+ | MLlam _ as a ->
+ let fl,a' = collect_lams a in
+ let fl,env' = push_vars fl env in
+ pp_abst (pp_expr env' [] a') (List.rev fl)
+ | MLletin (id,a1,a2) ->
+ let i,env' = push_vars [id] env in
+ apply
+ (hv 0
+ (hov 2
+ (paren
+ (str "let " ++
+ paren
+ (paren
+ (pr_id (List.hd i) ++ spc () ++ pp_expr env [] a1))
+ ++ spc () ++ hov 0 (pp_expr env' [] a2)))))
+ | MLglob r ->
+ apply (pp_global r)
+ | MLcons (r,args') ->
+ assert (args=[]);
+ let st =
+ str "`" ++
+ paren (pp_global r ++
+ (if args' = [] then mt () else (spc () ++ str ",")) ++
+ prlist_with_sep
+ (fun () -> spc () ++ str ",")
+ (pp_expr env []) args')
+ in
+ if Refset.mem r !cons_cofix then
+ paren (str "delay " ++ st)
+ else st
+ | MLcase (t, pv) ->
+ let r,_,_ = pv.(0) in
+ let e = if Refset.mem r !cons_cofix then
+ paren (str "force" ++ spc () ++ pp_expr env [] t)
+ else
+ pp_expr env [] t
+ in apply (v 3 (paren
+ (str "match-case " ++ e ++ fnl () ++ pp_pat env pv)))
+ | MLfix (i,ids,defs) ->
+ let ids',env' = push_vars (List.rev (Array.to_list ids)) env in
+ pp_fix env' i (Array.of_list (List.rev ids'),defs) args
+ | MLexn s ->
+ (* An [MLexn] may be applied, but I don't really care. *)
+ paren (str "absurd")
+ | MLdummy ->
+ str "__" (* An [MLdummy] may be applied, but I don't really care. *)
+ | MLmagic a ->
+ pp_expr env args a
+ | MLaxiom -> paren (str "absurd ;;AXIOM TO BE REALIZED\n")
+
+
+and pp_one_pat env (r,ids,t) =
+ let pp_arg id = str "?" ++ pr_id id in
+ let ids,env' = push_vars (List.rev ids) env in
+ let args =
+ if ids = [] then mt ()
+ else (str " " ++ prlist_with_sep spc pp_arg (List.rev ids))
+ in
+ (pp_global r ++ args), (pp_expr env' [] t)
+
+and pp_pat env pv =
+ prvect_with_sep fnl
+ (fun x -> let s1,s2 = pp_one_pat env x in
+ hov 2 (str "((" ++ s1 ++ str ")" ++ spc () ++ s2 ++ str ")")) pv
+
+(*s names of the functions ([ids]) are already pushed in [env],
+ and passed here just for convenience. *)
+
+and pp_fix env j (ids,bl) args =
+ paren
+ (str "letrec " ++
+ (v 0 (paren
+ (prvect_with_sep fnl
+ (fun (fi,ti) -> paren ((pr_id fi) ++ (pp_expr env [] ti)))
+ (array_map2 (fun id b -> (id,b)) ids bl)) ++
+ fnl () ++
+ hov 2 (pp_apply (pr_id (ids.(j))) true args))))
+
+(*s Pretty-printing of a declaration. *)
+
+let pp_decl _ = function
+ | Dind _ -> mt ()
+ | Dtype _ -> mt ()
+ | Dfix (rv, defs,_) ->
+ let ppv = Array.map pp_global rv in
+ prvect_with_sep fnl
+ (fun (pi,ti) ->
+ hov 2
+ (paren (str "define " ++ pi ++ spc () ++
+ (pp_expr (empty_env ()) [] ti))
+ ++ fnl ()))
+ (array_map2 (fun p b -> (p,b)) ppv defs) ++
+ fnl ()
+ | Dterm (r, a, _) ->
+ if is_inline_custom r then mt ()
+ else
+ hov 2 (paren (str "define " ++ pp_global r ++ spc () ++
+ pp_expr (empty_env ()) [] a)) ++ fnl () ++ fnl ()
+
+let pp_structure_elem mp = function
+ | (l,SEdecl d) -> pp_decl mp d
+ | (l,SEmodule m) ->
+ failwith "TODO: Scheme extraction of modules not implemented yet"
+ | (l,SEmodtype m) ->
+ failwith "TODO: Scheme extraction of modules not implemented yet"
+
+let pp_struct =
+ prlist (fun (mp,sel) -> prlist (pp_structure_elem mp) sel)
+
+let pp_signature s = assert false
+
+end
+