path: root/camlp4/ocaml_src/lib/grammar.ml

(* camlp4r *)
(***********************************************************************)
(*                                                                     *)
(*                             Camlp4                                  *)
(*                                                                     *)
(*        Daniel de Rauglaudre, projet Cristal, INRIA Rocquencourt     *)
(*                                                                     *)
(*  Copyright 2002 Institut National de Recherche en Informatique et   *)
(*  Automatique.  Distributed only by permission.                      *)
(*                                                                     *)
(***********************************************************************)

(* This file has been generated by program: do not edit! *)

open Stdpp;;
open Gramext;;
open Format;;

let rec flatten_tree =
  function
    DeadEnd -> []
  | LocAct (_, _) -> [[]]
  | Node {node = n; brother = b; son = s} ->
      List.map (fun l -> n :: l) (flatten_tree s) @ flatten_tree b
;;

let print_str ppf s = fprintf ppf "\"%s\"" (String.escaped s);;

let rec print_symbol ppf =
  function
    Smeta (n, sl, _) -> print_meta ppf n sl
  | Slist0 s -> fprintf ppf "LIST0 %a" print_symbol1 s
  | Slist0sep (s, t) ->
      fprintf ppf "LIST0 %a SEP %a" print_symbol1 s print_symbol1 t
  | Slist1 s -> fprintf ppf "LIST1 %a" print_symbol1 s
  | Slist1sep (s, t) ->
      fprintf ppf "LIST1 %a SEP %a" print_symbol1 s print_symbol1 t
  | Sopt s -> fprintf ppf "OPT %a" print_symbol1 s
  | Stoken (con, prm) when con <> "" && prm <> "" ->
      fprintf ppf "%s@ %a" con print_str prm
  | Snterml (e, l) -> fprintf ppf "%s@ LEVEL@ %a" e.ename print_str l
  | Snterm _ | Snext | Sself | Stoken _ | Stree _ as s -> print_symbol1 ppf s
and print_meta ppf n sl =
  let rec loop i =
    function
      [] -> ()
    | s :: sl ->
        let j =
          try String.index_from n i ' ' with
            Not_found -> String.length n
        in
        fprintf ppf "%s %a" (String.sub n i (j - i)) print_symbol1 s;
        if sl = [] then ()
        else
          begin fprintf ppf " "; loop (min (j + 1) (String.length n)) sl end
  in
  loop 0 sl
and print_symbol1 ppf =
  function
    Snterm e -> pp_print_string ppf e.ename
  | Sself -> pp_print_string ppf "SELF"
  | Snext -> pp_print_string ppf "NEXT"
  | Stoken ("", s) -> print_str ppf s
  | Stoken (con, "") -> pp_print_string ppf con
  | Stree t -> print_level ppf pp_print_space (flatten_tree t)
  | Smeta (_, _, _) | Snterml (_, _) | Slist0 _ | Slist0sep (_, _) |
    Slist1 _ | Slist1sep (_, _) | Sopt _ | Stoken _ as s ->
      fprintf ppf "(%a)" print_symbol s
and print_rule ppf symbols =
  fprintf ppf "@[<hov 0>";
  let _ =
    List.fold_left
      (fun sep symbol ->
         fprintf ppf "%t%a" sep print_symbol symbol;
         fun ppf -> fprintf ppf ";@ ")
      (fun ppf -> ()) symbols
  in
  fprintf ppf "@]"
and print_level ppf pp_print_space rules =
  fprintf ppf "@[<hov 0>[ ";
  let _ =
    List.fold_left
      (fun sep rule ->
         fprintf ppf "%t%a" sep print_rule rule;
         fun ppf -> fprintf ppf "%a| " pp_print_space ())
      (fun ppf -> ()) rules
  in
  fprintf ppf " ]@]"
;;

let print_levels ppf elev =
  let _ =
    List.fold_left
      (fun sep lev ->
         let rules =
           List.map (fun t -> Sself :: t) (flatten_tree lev.lsuffix) @
             flatten_tree lev.lprefix
         in
         fprintf ppf "%t@[<hov 2>" sep;
         begin match lev.lname with
           Some n -> fprintf ppf "%a@;<1 2>" print_str n
         | None -> ()
         end;
         begin match lev.assoc with
           LeftA -> fprintf ppf "LEFTA"
         | RightA -> fprintf ppf "RIGHTA"
         | NonA -> fprintf ppf "NONA"
         end;
         fprintf ppf "@]@;<1 2>";
         print_level ppf pp_force_newline rules;
         fun ppf -> fprintf ppf "@,| ")
      (fun ppf -> ()) elev
  in
  ()
;;

let print_entry ppf e =
  fprintf ppf "@[<v 0>[ ";
  begin match e.edesc with
    Dlevels elev -> print_levels ppf elev
  | Dparser _ -> fprintf ppf "<parser>"
  end;
  fprintf ppf " ]@]"
;;

let iter_entry f e =
  let treated = ref [] in
  let rec do_entry e =
    if List.memq e !treated then ()
    else
      begin
        treated := e :: !treated;
        f e;
        match e.edesc with
          Dlevels ll -> List.iter do_level ll
        | Dparser _ -> ()
      end
  and do_level lev = do_tree lev.lsuffix; do_tree lev.lprefix
  and do_tree =
    function
      Node n -> do_node n
    | LocAct (_, _) | DeadEnd -> ()
  and do_node n = do_symbol n.node; do_tree n.son; do_tree n.brother
  and do_symbol =
    function
      Smeta (_, sl, _) -> List.iter do_symbol sl
    | Snterm e | Snterml (e, _) -> do_entry e
    | Slist0 s | Slist1 s | Sopt s -> do_symbol s
    | Slist0sep (s1, s2) | Slist1sep (s1, s2) -> do_symbol s1; do_symbol s2
    | Stree t -> do_tree t
    | Sself | Snext | Stoken _ -> ()
  in
  do_entry e
;;

let fold_entry f e init =
  let treated = ref [] in
  let rec do_entry accu e =
    if List.memq e !treated then accu
    else
      begin
        treated := e :: !treated;
        let accu = f e accu in
        match e.edesc with
          Dlevels ll -> List.fold_left do_level accu ll
        | Dparser _ -> accu
      end
  and do_level accu lev =
    let accu = do_tree accu lev.lsuffix in do_tree accu lev.lprefix
  and do_tree accu =
    function
      Node n -> do_node accu n
    | LocAct (_, _) | DeadEnd -> accu
  and do_node accu n =
    let accu = do_symbol accu n.node in
    let accu = do_tree accu n.son in do_tree accu n.brother
  and do_symbol accu =
    function
      Smeta (_, sl, _) -> List.fold_left do_symbol accu sl
    | Snterm e | Snterml (e, _) -> do_entry accu e
    | Slist0 s | Slist1 s | Sopt s -> do_symbol accu s
    | Slist0sep (s1, s2) | Slist1sep (s1, s2) ->
        let accu = do_symbol accu s1 in do_symbol accu s2
    | Stree t -> do_tree accu t
    | Sself | Snext | Stoken _ -> accu
  in
  do_entry init e
;;

type g = Token.t Gramext.grammar;;

external grammar_obj : g -> Token.t grammar = "%identity";;

let floc = ref (fun _ -> failwith "internal error when computing location");;
let loc_of_token_interval bp ep =
  if bp == ep then
    if bp == 0 then 0, 1 else let a = snd (!floc (bp - 1)) in a, a + 1
  else
    let (bp1, bp2) = !floc bp in
    let (ep1, ep2) = !floc (pred ep) in
    (if bp1 < ep1 then bp1 else ep1), (if bp2 > ep2 then bp2 else ep2)
;;

let rec name_of_symbol entry =
  function
    Snterm e -> "[" ^ e.ename ^ "]"
  | Snterml (e, l) -> "[" ^ e.ename ^ " level " ^ l ^ "]"
  | Sself | Snext -> "[" ^ entry.ename ^ "]"
  | Stoken tok -> entry.egram.glexer.Token.tok_text tok
  | _ -> "???"
;;

let rec get_token_list entry tokl last_tok tree =
  match tree with
    Node {node = Stoken tok as s; son = son; brother = DeadEnd} ->
      get_token_list entry (last_tok :: tokl) tok son
  | _ ->
      if tokl = [] then None
      else Some (List.rev (last_tok :: tokl), last_tok, tree)
;;

let rec name_of_symbol_failed entry =
  function
    Slist0 s -> name_of_symbol_failed entry s
  | Slist0sep (s, _) -> name_of_symbol_failed entry s
  | Slist1 s -> name_of_symbol_failed entry s
  | Slist1sep (s, _) -> name_of_symbol_failed entry s
  | Sopt s -> name_of_symbol_failed entry s
  | Stree t -> name_of_tree_failed entry t
  | s -> name_of_symbol entry s
and name_of_tree_failed entry =
  function
    Node {node = s; brother = bro; son = son} ->
      let tokl =
        match s with
          Stoken tok -> get_token_list entry [] tok son
        | _ -> None
      in
      begin match tokl with
        None ->
          let txt = name_of_symbol_failed entry s in
          let txt =
            match s, son with
              Sopt _, Node _ -> txt ^ " or " ^ name_of_tree_failed entry son
            | _ -> txt
          in
          let txt =
            match bro with
              DeadEnd | LocAct (_, _) -> txt
            | Node _ -> txt ^ " or " ^ name_of_tree_failed entry bro
          in
          txt
      | Some (tokl, last_tok, son) ->
          List.fold_left
            (fun s tok ->
               (if s = "" then "" else s ^ " ") ^
                 entry.egram.glexer.Token.tok_text tok)
            "" tokl
      end
  | DeadEnd | LocAct (_, _) -> "???"
;;

let search_tree_in_entry prev_symb tree =
  function
    Dlevels levels ->
      let rec search_levels =
        function
          [] -> tree
        | level :: levels ->
            match search_level level with
              Some tree -> tree
            | None -> search_levels levels
      and search_level level =
        match search_tree level.lsuffix with
          Some t -> Some (Node {node = Sself; son = t; brother = DeadEnd})
        | None -> search_tree level.lprefix
      and search_tree t =
        if tree <> DeadEnd && t == tree then Some t
        else
          match t with
            Node n ->
              begin match search_symbol n.node with
                Some symb ->
                  Some (Node {node = symb; son = n.son; brother = DeadEnd})
              | None ->
                  match search_tree n.son with
                    Some t ->
                      Some (Node {node = n.node; son = t; brother = DeadEnd})
                  | None -> search_tree n.brother
              end
          | LocAct (_, _) | DeadEnd -> None
      and search_symbol symb =
        match symb with
          Snterm _ | Snterml (_, _) | Slist0 _ | Slist0sep (_, _) | Slist1 _ |
          Slist1sep (_, _) | Sopt _ | Stoken _ | Stree _
          when symb == prev_symb ->
            Some symb
        | Slist0 symb ->
            begin match search_symbol symb with
              Some symb -> Some (Slist0 symb)
            | None -> None
            end
        | Slist0sep (symb, sep) ->
            begin match search_symbol symb with
              Some symb -> Some (Slist0sep (symb, sep))
            | None ->
                match search_symbol sep with
                  Some sep -> Some (Slist0sep (symb, sep))
                | None -> None
            end
        | Slist1 symb ->
            begin match search_symbol symb with
              Some symb -> Some (Slist1 symb)
            | None -> None
            end
        | Slist1sep (symb, sep) ->
            begin match search_symbol symb with
              Some symb -> Some (Slist1sep (symb, sep))
            | None ->
                match search_symbol sep with
                  Some sep -> Some (Slist1sep (symb, sep))
                | None -> None
            end
        | Sopt symb ->
            begin match search_symbol symb with
              Some symb -> Some (Sopt symb)
            | None -> None
            end
        | Stree t ->
            begin match search_tree t with
              Some t -> Some (Stree t)
            | None -> None
            end
        | _ -> None
      in
      search_levels levels
  | Dparser _ -> tree
;;

let error_verbose = ref false;;

let tree_failed entry prev_symb_result prev_symb tree =
  let txt = name_of_tree_failed entry tree in
  let txt =
    match prev_symb with
      Slist0 s ->
        let txt1 = name_of_symbol_failed entry s in
        txt1 ^ " or " ^ txt ^ " expected"
    | Slist1 s ->
        let txt1 = name_of_symbol_failed entry s in
        txt1 ^ " or " ^ txt ^ " expected"
    | Slist0sep (s, sep) ->
        begin match Obj.magic prev_symb_result with
          [] ->
            let txt1 = name_of_symbol_failed entry s in
            txt1 ^ " or " ^ txt ^ " expected"
        | _ ->
            let txt1 = name_of_symbol_failed entry sep in
            txt1 ^ " or " ^ txt ^ " expected"
        end
    | Slist1sep (s, sep) ->
        begin match Obj.magic prev_symb_result with
          [] ->
            let txt1 = name_of_symbol_failed entry s in
            txt1 ^ " or " ^ txt ^ " expected"
        | _ ->
            let txt1 = name_of_symbol_failed entry sep in
            txt1 ^ " or " ^ txt ^ " expected"
        end
    | Sopt _ | Stree _ -> txt ^ " expected"
    | _ -> txt ^ " expected after " ^ name_of_symbol entry prev_symb
  in
  if !error_verbose then
    begin
      let tree = search_tree_in_entry prev_symb tree entry.edesc in
      let ppf = err_formatter in
      fprintf ppf "@[<v 0>@,";
      fprintf ppf "----------------------------------@,";
      fprintf ppf "Parse error in entry [%s], rule:@;<0 2>" entry.ename;
      fprintf ppf "@[";
      print_level ppf pp_force_newline (flatten_tree tree);
      fprintf ppf "@]@,";
      fprintf ppf "----------------------------------@,";
      fprintf ppf "@]@."
    end;
  txt ^ " (in [" ^ entry.ename ^ "])"
;;

let symb_failed entry prev_symb_result prev_symb symb =
  let tree = Node {node = symb; brother = DeadEnd; son = DeadEnd} in
  tree_failed entry prev_symb_result prev_symb tree
;;

external app : Obj.t -> 'a = "%identity";;

let is_level_labelled n lev =
  match lev.lname with
    Some n1 -> n = n1
  | None -> false
;;

let level_number entry lab =
  let rec lookup levn =
    function
      [] -> failwith ("unknown level " ^ lab)
    | lev :: levs ->
        if is_level_labelled lab lev then levn else lookup (succ levn) levs
  in
  match entry.edesc with
    Dlevels elev -> lookup 0 elev
  | Dparser _ -> raise Not_found
;;

let rec top_symb entry =
  function
    Sself | Snext -> Snterm entry
  | Snterml (e, _) -> Snterm e
  | Slist1sep (s, sep) -> Slist1sep (top_symb entry s, sep)
  | _ -> raise Stream.Failure
;;

let entry_of_symb entry =
  function
    Sself | Snext -> entry
  | Snterm e -> e
  | Snterml (e, _) -> e
  | _ -> raise Stream.Failure
;;

let top_tree entry =
  function
    Node {node = s; brother = bro; son = son} ->
      Node {node = top_symb entry s; brother = bro; son = son}
  | LocAct (_, _) | DeadEnd -> raise Stream.Failure
;;

let skip_if_empty bp p strm =
  if Stream.count strm == bp then Gramext.action (fun a -> p strm)
  else raise Stream.Failure
;;

let continue entry bp a s son p1 (strm__ : _ Stream.t) =
  let a = (entry_of_symb entry s).econtinue 0 bp a strm__ in
  let act =
    try p1 strm__ with
      Stream.Failure -> raise (Stream.Error (tree_failed entry a s son))
  in
  Gramext.action (fun _ -> app act a)
;;

let do_recover
  parser_of_tree entry nlevn alevn bp a s son (strm__ : _ Stream.t) =
  try parser_of_tree entry nlevn alevn (top_tree entry son) strm__ with
    Stream.Failure ->
      try
        skip_if_empty bp (fun (strm__ : _ Stream.t) -> raise Stream.Failure)
          strm__
      with
        Stream.Failure ->
          continue entry bp a s son (parser_of_tree entry nlevn alevn son)
            strm__
;;

let strict_parsing = ref false;;

let recover parser_of_tree entry nlevn alevn bp a s son strm =
  if !strict_parsing then raise (Stream.Error (tree_failed entry a s son))
  else do_recover parser_of_tree entry nlevn alevn bp a s son strm
;;

let token_count = ref 0;;

let peek_nth n strm =
  let list = Stream.npeek n strm in
  token_count := Stream.count strm + n;
  let rec loop list n =
    match list, n with
      x :: _, 1 -> Some x
    | _ :: l, n -> loop l (n - 1)
    | [], _ -> None
  in
  loop list n
;;

let rec parser_of_tree entry nlevn alevn =
  function
    DeadEnd -> (fun (strm__ : _ Stream.t) -> raise Stream.Failure)
  | LocAct (act, _) -> (fun (strm__ : _ Stream.t) -> act)
  | Node {node = Sself; son = LocAct (act, _); brother = DeadEnd} ->
      (fun (strm__ : _ Stream.t) ->
         let a = entry.estart alevn strm__ in app act a)
  | Node {node = Sself; son = LocAct (act, _); brother = bro} ->
      let p2 = parser_of_tree entry nlevn alevn bro in
      (fun (strm__ : _ Stream.t) ->
         match
           try Some (entry.estart alevn strm__) with
             Stream.Failure -> None
         with
           Some a -> app act a
         | _ -> p2 strm__)
  | Node {node = s; son = son; brother = DeadEnd} ->
      let tokl =
        match s with
          Stoken tok -> get_token_list entry [] tok son
        | _ -> None
      in
      begin match tokl with
        None ->
          let ps = parser_of_symbol entry nlevn s in
          let p1 = parser_of_tree entry nlevn alevn son in
          let p1 = parser_cont p1 entry nlevn alevn s son in
          (fun (strm__ : _ Stream.t) ->
             let bp = Stream.count strm__ in
             let a = ps strm__ in
             let act =
               try p1 bp a strm__ with
                 Stream.Failure -> raise (Stream.Error "")
             in
             app act a)
      | Some (tokl, last_tok, son) ->
          let p1 = parser_of_tree entry nlevn alevn son in
          let p1 = parser_cont p1 entry nlevn alevn (Stoken last_tok) son in
          parser_of_token_list entry.egram p1 tokl
      end
  | Node {node = s; son = son; brother = bro} ->
      let tokl =
        match s with
          Stoken tok -> get_token_list entry [] tok son
        | _ -> None
      in
      match tokl with
        None ->
          let ps = parser_of_symbol entry nlevn s in
          let p1 = parser_of_tree entry nlevn alevn son in
          let p1 = parser_cont p1 entry nlevn alevn s son in
          let p2 = parser_of_tree entry nlevn alevn bro in
          (fun (strm__ : _ Stream.t) ->
             let bp = Stream.count strm__ in
             match
               try Some (ps strm__) with
                 Stream.Failure -> None
             with
               Some a ->
                 let act =
                   try p1 bp a strm__ with
                     Stream.Failure -> raise (Stream.Error "")
                 in
                 app act a
             | _ -> p2 strm__)
      | Some (tokl, last_tok, son) ->
          let p1 = parser_of_tree entry nlevn alevn son in
          let p1 = parser_cont p1 entry nlevn alevn (Stoken last_tok) son in
          let p1 = parser_of_token_list entry.egram p1 tokl in
          let p2 = parser_of_tree entry nlevn alevn bro in
          fun (strm__ : _ Stream.t) ->
            try p1 strm__ with
              Stream.Failure -> p2 strm__
and parser_cont p1 entry nlevn alevn s son bp a (strm__ : _ Stream.t) =
  try p1 strm__ with
    Stream.Failure ->
      try recover parser_of_tree entry nlevn alevn bp a s son strm__ with
        Stream.Failure -> raise (Stream.Error (tree_failed entry a s son))
and parser_of_token_list gram p1 tokl =
  let rec loop n =
    function
      tok :: tokl ->
        let tematch = gram.glexer.Token.tok_match tok in
        begin match tokl with
          [] ->
            let ps strm =
              match peek_nth n strm with
                Some tok ->
                  let r = tematch tok in
                  for i = 1 to n do Stream.junk strm done; Obj.repr r
              | None -> raise Stream.Failure
            in
            (fun (strm__ : _ Stream.t) ->
               let bp = Stream.count strm__ in
               let a = ps strm__ in
               let act =
                 try p1 bp a strm__ with
                   Stream.Failure -> raise (Stream.Error "")
               in
               app act a)
        | _ ->
            let ps strm =
              match peek_nth n strm with
                Some tok -> tematch tok
              | None -> raise Stream.Failure
            in
            let p1 = loop (n + 1) tokl in
            fun (strm__ : _ Stream.t) ->
              let a = ps strm__ in let act = p1 strm__ in app act a
        end
    | [] -> invalid_arg "parser_of_token_list"
  in
  loop 1 tokl
and parser_of_symbol entry nlevn =
  function
    Smeta (_, symbl, act) ->
      let act = Obj.magic act entry symbl in
      Obj.magic
        (List.fold_left
           (fun act symb -> Obj.magic act (parser_of_symbol entry nlevn symb))
           act symbl)
  | Slist0 s ->
      let ps = parser_of_symbol entry nlevn s in
      let rec loop al (strm__ : _ Stream.t) =
        match
          try Some (ps strm__) with
            Stream.Failure -> None
        with
          Some a -> loop (a :: al) strm__
        | _ -> al
      in
      (fun (strm__ : _ Stream.t) ->
         let a = loop [] strm__ in Obj.repr (List.rev a))
  | Slist0sep (symb, sep) ->
      let ps = parser_of_symbol entry nlevn symb in
      let pt = parser_of_symbol entry nlevn sep in
      let rec kont al (strm__ : _ Stream.t) =
        match
          try Some (pt strm__) with
            Stream.Failure -> None
        with
          Some v ->
            let a =
              try ps strm__ with
                Stream.Failure ->
                  raise (Stream.Error (symb_failed entry v sep symb))
            in
            kont (a :: al) strm__
        | _ -> al
      in
      (fun (strm__ : _ Stream.t) ->
         match
           try Some (ps strm__) with
             Stream.Failure -> None
         with
           Some a -> Obj.repr (List.rev (kont [a] strm__))
         | _ -> Obj.repr [])
  | Slist1 s ->
      let ps = parser_of_symbol entry nlevn s in
      let rec loop al (strm__ : _ Stream.t) =
        match
          try Some (ps strm__) with
            Stream.Failure -> None
        with
          Some a -> loop (a :: al) strm__
        | _ -> al
      in
      (fun (strm__ : _ Stream.t) ->
         let a = ps strm__ in Obj.repr (List.rev (loop [a] strm__)))
  | Slist1sep (symb, sep) ->
      let ps = parser_of_symbol entry nlevn symb in
      let pt = parser_of_symbol entry nlevn sep in
      let rec kont al (strm__ : _ Stream.t) =
        match
          try Some (pt strm__) with
            Stream.Failure -> None
        with
          Some v ->
            let a =
              try ps strm__ with
                Stream.Failure ->
                  try parse_top_symb entry symb strm__ with
                    Stream.Failure ->
                      raise (Stream.Error (symb_failed entry v sep symb))
            in
            kont (a :: al) strm__
        | _ -> al
      in
      (fun (strm__ : _ Stream.t) ->
         let a = ps strm__ in Obj.repr (List.rev (kont [a] strm__)))
  | Sopt s ->
      let ps = parser_of_symbol entry nlevn s in
      (fun (strm__ : _ Stream.t) ->
         match
           try Some (ps strm__) with
             Stream.Failure -> None
         with
           Some a -> Obj.repr (Some a)
         | _ -> Obj.repr None)
  | Stree t ->
      let pt = parser_of_tree entry 1 0 t in
      (fun (strm__ : _ Stream.t) ->
         let bp = Stream.count strm__ in
         let a = pt strm__ in
         let ep = Stream.count strm__ in
         let loc = loc_of_token_interval bp ep in app a loc)
  | Snterm e -> (fun (strm__ : _ Stream.t) -> e.estart 0 strm__)
  | Snterml (e, l) ->
      (fun (strm__ : _ Stream.t) -> e.estart (level_number e l) strm__)
  | Sself -> (fun (strm__ : _ Stream.t) -> entry.estart 0 strm__)
  | Snext -> (fun (strm__ : _ Stream.t) -> entry.estart nlevn strm__)
  | Stoken tok ->
      let f = entry.egram.glexer.Token.tok_match tok in
      fun strm ->
        match Stream.peek strm with
          Some tok -> let r = f tok in Stream.junk strm; Obj.repr r
        | None -> raise Stream.Failure
and parse_top_symb entry symb =
  parser_of_symbol entry 0 (top_symb entry symb)
;;

let symb_failed_txt e s1 s2 = symb_failed e 0 s1 s2;;

let rec continue_parser_of_levels entry clevn =
  function
    [] -> (fun levn bp a (strm__ : _ Stream.t) -> raise Stream.Failure)
  | lev :: levs ->
      let p1 = continue_parser_of_levels entry (succ clevn) levs in
      match lev.lsuffix with
        DeadEnd -> p1
      | tree ->
          let alevn =
            match lev.assoc with
              LeftA | NonA -> succ clevn
            | RightA -> clevn
          in
          let p2 = parser_of_tree entry (succ clevn) alevn tree in
          fun levn bp a strm ->
            if levn > clevn then p1 levn bp a strm
            else
              let (strm__ : _ Stream.t) = strm in
              try p1 levn bp a strm__ with
                Stream.Failure ->
                  let act = p2 strm__ in
                  let ep = Stream.count strm__ in
                  let a = app act a (loc_of_token_interval bp ep) in
                  entry.econtinue levn bp a strm
;;

let rec start_parser_of_levels entry clevn =
  function
    [] -> (fun levn (strm__ : _ Stream.t) -> raise Stream.Failure)
  | lev :: levs ->
      let p1 = start_parser_of_levels entry (succ clevn) levs in
      match lev.lprefix with
        DeadEnd -> p1
      | tree ->
          let alevn =
            match lev.assoc with
              LeftA | NonA -> succ clevn
            | RightA -> clevn
          in
          let p2 = parser_of_tree entry (succ clevn) alevn tree in
          match levs with
            [] ->
              (fun levn strm ->
                 let (strm__ : _ Stream.t) = strm in
                 let bp = Stream.count strm__ in
                 let act = p2 strm__ in
                 let ep = Stream.count strm__ in
                 let a = app act (loc_of_token_interval bp ep) in
                 entry.econtinue levn bp a strm)
          | _ ->
              fun levn strm ->
                if levn > clevn then p1 levn strm
                else
                  let (strm__ : _ Stream.t) = strm in
                  let bp = Stream.count strm__ in
                  match
                    try Some (p2 strm__) with
                      Stream.Failure -> None
                  with
                    Some act ->
                      let ep = Stream.count strm__ in
                      let a = app act (loc_of_token_interval bp ep) in
                      entry.econtinue levn bp a strm
                  | _ -> p1 levn strm__
;;

let continue_parser_of_entry entry =
  match entry.edesc with
    Dlevels elev ->
      let p = continue_parser_of_levels entry 0 elev in
      (fun levn bp a (strm__ : _ Stream.t) ->
         try p levn bp a strm__ with
           Stream.Failure -> a)
  | Dparser p -> fun levn bp a (strm__ : _ Stream.t) -> raise Stream.Failure
;;

let empty_entry ename levn strm =
  raise (Stream.Error ("entry [" ^ ename ^ "] is empty"))
;;

let start_parser_of_entry entry =
  match entry.edesc with
    Dlevels [] -> empty_entry entry.ename
  | Dlevels elev -> start_parser_of_levels entry 0 elev
  | Dparser p -> fun levn strm -> p strm
;;

let parse_parsable entry efun (cs, (ts, fun_loc)) =
  let restore =
    let old_floc = !floc in
    let old_tc = !token_count in
    fun () -> floc := old_floc; token_count := old_tc
  in
  let get_loc () =
    try
      let cnt = Stream.count ts in
      let loc = fun_loc cnt in
      if !token_count - 1 <= cnt then loc
      else fst loc, snd (fun_loc (!token_count - 1))
    with
      _ -> Stream.count cs, Stream.count cs + 1
  in
  floc := fun_loc;
  token_count := 0;
  try let r = efun ts in restore (); r with
    Stream.Failure ->
      let loc = get_loc () in
      restore ();
      raise_with_loc loc (Stream.Error ("illegal begin of " ^ entry.ename))
  | Stream.Error _ as exc ->
      let loc = get_loc () in restore (); raise_with_loc loc exc
  | exc ->
      let loc = Stream.count cs, Stream.count cs + 1 in
      restore (); raise_with_loc loc exc
;;

let wrap_parse entry efun cs =
  let parsable = cs, entry.egram.glexer.Token.tok_func cs in
  parse_parsable entry efun parsable
;;

let create_toktab () = Hashtbl.create 301;;
let gcreate glexer = {gtokens = create_toktab (); glexer = glexer};;

let tematch tparse tok =
  match tparse tok with
    Some p -> (fun x -> p (Stream.ising x))
  | None -> Token.default_match tok
;;
let glexer_of_lexer lexer =
  {Token.tok_func = lexer.Token.func; Token.tok_using = lexer.Token.using;
   Token.tok_removing = lexer.Token.removing;
   Token.tok_match = tematch lexer.Token.tparse;
   Token.tok_text = lexer.Token.text; Token.tok_comm = None}
;;
let create lexer = gcreate (glexer_of_lexer lexer);;

(* Extend syntax *)

let extend_entry entry position rules =
  try
    let elev = Gramext.levels_of_rules entry position rules in
    entry.edesc <- Dlevels elev;
    entry.estart <-
      (fun lev strm ->
         let f = start_parser_of_entry entry in
         entry.estart <- f; f lev strm);
    entry.econtinue <-
      fun lev bp a strm ->
        let f = continue_parser_of_entry entry in
        entry.econtinue <- f; f lev bp a strm
  with
    Token.Error s ->
      Printf.eprintf "Lexer initialization error:\n- %s\n" s;
      flush stderr;
      failwith "Grammar.extend"
;;

let extend entry_rules_list =
  let gram = ref None in
  List.iter
    (fun (entry, position, rules) ->
       begin match !gram with
         Some g ->
           if g != entry.egram then
             begin
               Printf.eprintf "Error: entries with different grammars\n";
               flush stderr;
               failwith "Grammar.extend"
             end
       | None -> gram := Some entry.egram
       end;
       extend_entry entry position rules)
    entry_rules_list
;;

(* Deleting a rule *)

let delete_rule entry sl =
  match entry.edesc with
    Dlevels levs ->
      let levs = Gramext.delete_rule_in_level_list entry sl levs in
      entry.edesc <- Dlevels levs;
      entry.estart <-
        (fun lev strm ->
           let f = start_parser_of_entry entry in
           entry.estart <- f; f lev strm);
      entry.econtinue <-
        (fun lev bp a strm ->
           let f = continue_parser_of_entry entry in
           entry.econtinue <- f; f lev bp a strm)
  | Dparser _ -> ()
;;

(* Unsafe *)

let clear_entry e =
  e.estart <- (fun _ (strm__ : _ Stream.t) -> raise Stream.Failure);
  e.econtinue <- (fun _ _ _ (strm__ : _ Stream.t) -> raise Stream.Failure);
  match e.edesc with
    Dlevels _ -> e.edesc <- Dlevels []
  | Dparser _ -> ()
;;

let gram_reinit g glexer = Hashtbl.clear g.gtokens; g.glexer <- glexer;;

let reinit_gram g lexer = gram_reinit g (glexer_of_lexer lexer);;

module Unsafe =
  struct
    let gram_reinit = gram_reinit;;
    let clear_entry = clear_entry;;
    let reinit_gram = reinit_gram;;
  end
;;

let find_entry e s =
  let rec find_levels =
    function
      [] -> None
    | lev :: levs ->
        match find_tree lev.lsuffix with
          None ->
            begin match find_tree lev.lprefix with
              None -> find_levels levs
            | x -> x
            end
        | x -> x
  and find_symbol =
    function
      Snterm e -> if e.ename = s then Some e else None
    | Snterml (e, _) -> if e.ename = s then Some e else None
    | Smeta (_, sl, _) -> find_symbol_list sl
    | Slist0 s -> find_symbol s
    | Slist0sep (s, _) -> find_symbol s
    | Slist1 s -> find_symbol s
    | Slist1sep (s, _) -> find_symbol s
    | Sopt s -> find_symbol s
    | Stree t -> find_tree t
    | Sself | Snext | Stoken _ -> None
  and find_symbol_list =
    function
      s :: sl ->
        begin match find_symbol s with
          None -> find_symbol_list sl
        | x -> x
        end
    | [] -> None
  and find_tree =
    function
      Node {node = s; brother = bro; son = son} ->
        begin match find_symbol s with
          None ->
            begin match find_tree bro with
              None -> find_tree son
            | x -> x
            end
        | x -> x
        end
    | LocAct (_, _) | DeadEnd -> None
  in
  match e.edesc with
    Dlevels levs ->
      begin match find_levels levs with
        Some e -> e
      | None -> raise Not_found
      end
  | Dparser _ -> raise Not_found
;;

let of_entry e = e.egram;;

module Entry =
  struct
    type te = Token.t;;
    type 'a e = te g_entry;;
    let create g n =
      {egram = g; ename = n; estart = empty_entry n;
       econtinue = (fun _ _ _ (strm__ : _ Stream.t) -> raise Stream.Failure);
       edesc = Dlevels []}
    ;;
    let parse (entry : 'a e) cs : 'a =
      Obj.magic (wrap_parse entry (entry.estart 0) cs)
    ;;
    let parse_token (entry : 'a e) ts : 'a = Obj.magic (entry.estart 0 ts);;
    let name e = e.ename;;
    let of_parser g n (p : te Stream.t -> 'a) : 'a e =
      {egram = g; ename = n; estart = (fun _ -> Obj.magic p);
       econtinue = (fun _ _ _ (strm__ : _ Stream.t) -> raise Stream.Failure);
       edesc = Dparser (Obj.magic p)}
    ;;
    external obj : 'a e -> te Gramext.g_entry = "%identity";;
    let print e = printf "%a@." print_entry (obj e);;
    let find e s = find_entry (obj e) s;;
  end
;;

let tokens g con =
  let list = ref [] in
  Hashtbl.iter
    (fun (p_con, p_prm) c -> if p_con = con then list := (p_prm, !c) :: !list)
    g.gtokens;
  !list
;;

let glexer g = g.glexer;;

let warning_verbose = Gramext.warning_verbose;;

(* Functorial interface *)

module type GLexerType = sig type te;; val lexer : te Token.glexer;; end;;

module type S =
  sig
    type te;;
    type parsable;;
    val parsable : char Stream.t -> parsable;;
    val tokens : string -> (string * int) list;;
    val glexer : te Token.glexer;;
    module Entry :
      sig
        type 'a e;;
        val create : string -> 'a e;;
        val parse : 'a e -> parsable -> 'a;;
        val parse_token : 'a e -> te Stream.t -> 'a;;
        val name : 'a e -> string;;
        val of_parser : string -> (te Stream.t -> 'a) -> 'a e;;
        val print : 'a e -> unit;;
        external obj : 'a e -> te Gramext.g_entry = "%identity";;
      end
    ;;
    module Unsafe :
      sig
        val gram_reinit : te Token.glexer -> unit;;
        val clear_entry : 'a Entry.e -> unit;;
        val reinit_gram : Token.lexer -> unit;;
      end
    ;;
    val extend :
      'a Entry.e -> Gramext.position option ->
        (string option * Gramext.g_assoc option *
           (te Gramext.g_symbol list * Gramext.g_action) list)
          list ->
        unit;;
    val delete_rule : 'a Entry.e -> te Gramext.g_symbol list -> unit;;
  end
;;

module type ReinitType = sig val reinit_gram : g -> Token.lexer -> unit;; end
;;

module GGMake (R : ReinitType) (L : GLexerType) =
  struct
    type te = L.te;;
    type parsable = char Stream.t * (te Stream.t * Token.location_function);;
    let gram = gcreate L.lexer;;
    let parsable cs = cs, L.lexer.Token.tok_func cs;;
    let tokens = tokens gram;;
    let glexer = glexer gram;;
    module Entry =
      struct
        type 'a e = te g_entry;;
        let create n =
          {egram = gram; ename = n; estart = empty_entry n;
           econtinue =
             (fun _ _ _ (strm__ : _ Stream.t) -> raise Stream.Failure);
           edesc = Dlevels []}
        ;;
        external obj : 'a e -> te Gramext.g_entry = "%identity";;
        let parse (e : 'a e) p : 'a =
          Obj.magic (parse_parsable e (e.estart 0) p)
        ;;
        let parse_token (e : 'a e) ts : 'a = Obj.magic (e.estart 0 ts);;
        let name e = e.ename;;
        let of_parser n (p : te Stream.t -> 'a) : 'a e =
          {egram = gram; ename = n; estart = (fun _ -> Obj.magic p);
           econtinue =
             (fun _ _ _ (strm__ : _ Stream.t) -> raise Stream.Failure);
           edesc = Dparser (Obj.magic p)}
        ;;
        let print e = printf "%a@." print_entry (obj e);;
      end
    ;;
    module Unsafe =
      struct
        let gram_reinit = gram_reinit gram;;
        let clear_entry = Unsafe.clear_entry;;
        let reinit_gram = R.reinit_gram (Obj.magic gram);;
      end
    ;;
    let extend = extend_entry;;
    let delete_rule e r = delete_rule (Entry.obj e) r;;
  end
;;

module GMake (L : GLexerType) =
  GGMake
    (struct
       let reinit_gram _ _ =
         failwith "call of deprecated reinit_gram in grammar built by GMake"
       ;;
     end)
    (L)
;;

module type LexerType = sig val lexer : Token.lexer;; end;;

module Make (L : LexerType) =
  GGMake (struct let reinit_gram = reinit_gram;; end)
    (struct type te = Token.t;; let lexer = glexer_of_lexer L.lexer;; end)
;;