make UTop_camlp4 public so the user can reuse it

Ignore-this: 103cabecad95046cf6686b55028de6c9

darcs-hash:20120220101444-c41ad-5e51be240cb26f1ca02fc37655d464b5acf1cbab

_oasis

@@ -47,7 +47,7 @@ Library "utop-camlp4"
   FindlibName: camlp4
   FindlibParent: utop
   Path: src/camlp4
-  InternalModules: UTop_camlp4
+  Modules: UTop_camlp4
   BuildDepends: utop, camlp4
   XMETAType: syntax
   XMETADescription: Camlp4 integration

src/camlp4/uTop_camlp4.ml

@@ -15,6 +15,9 @@ module Ast2pt = Camlp4.Struct.Camlp4Ast2OCamlAst.Make(Ast)
 
 external cast_toplevel_phrase : Camlp4_import.Parsetree.toplevel_phrase -> Parsetree.toplevel_phrase = "%identity"
 
+let convert_camlp4_toplevel_phrase ast =
+  cast_toplevel_phrase (Ast2pt.phrase ast)
+
 let print_camlp4_error pp exn =
   Format.fprintf pp "@[<0>%a@]" Camlp4.ErrorHandler.print exn;
   Format.pp_print_flush pp ()
@@ -36,9 +39,9 @@ let parse_toplevel_phrase_camlp4 str eos_is_error =
                  Some x)
     in
     match Gram.parse_tokens_after_filter Syntax.top_phrase token_stream with
-      | Some str_item ->
+      | Some ast ->
-          let str_item = AstFilters.fold_topphrase_filters (fun t filter -> filter t) str_item in
+          let ast = AstFilters.fold_topphrase_filters (fun t filter -> filter t) ast in
-          UTop.Value (cast_toplevel_phrase (Ast2pt.phrase str_item))
+          UTop.Value ast
       | None ->
           raise UTop.Need_more
   with exn ->
@@ -48,15 +51,22 @@ let parse_toplevel_phrase_camlp4 str eos_is_error =
       let locs, exn =
         match exn with
           | Loc.Exc_located (loc, exn) ->
-              ([(Loc.start_off loc,Loc.stop_off loc)], exn)
+              ([(Loc.start_off loc, Loc.stop_off loc)], exn)
           | exn ->
               ([], exn)
       in
       UTop.Error (locs, UTop.get_message print_camlp4_error exn)
 
+let parse_toplevel_phrase str eos_is_error =
+  match parse_toplevel_phrase_camlp4 str eos_is_error with
+    | UTop.Value ast ->
+        UTop.Value (convert_camlp4_toplevel_phrase ast)
+    | UTop.Error (locs, msg) ->
+        UTop.Error (locs, msg)
+
 let () =
   UTop.set_camlp4 true;
-  UTop.parse_toplevel_phrase := parse_toplevel_phrase_camlp4;
+  UTop.parse_toplevel_phrase := parse_toplevel_phrase;
   (* Force camlp4 to display its welcome message. *)
   try
     ignore (!Toploop.parse_toplevel_phrase (Lexing.from_string ""))

src/camlp4/uTop_camlp4.mli

@@ -0,0 +1,19 @@
+(*
+ * uTop_camlp4.mli
+ * ---------------
+ * Copyright : (c) 2012, Jeremie Dimino <jeremie@dimino.org>
+ * Licence   : BSD3
+ *
+ * This file is a part of utop.
+ *)
+
+val parse_toplevel_phrase : string -> bool -> Parsetree.toplevel_phrase UTop.result
+  (** Toplevel phrase parser for utop using camlp4. *)
+
+val parse_toplevel_phrase_camlp4 : string -> bool -> Camlp4.PreCast.Ast.str_item UTop.result
+  (** Camlp4 toplevel phrase parser. Same as {!parse_toplevel_phrase}
+      but the result is not converted to an OCaml ast. *)
+
+val convert_camlp4_toplevel_phrase : Camlp4.PreCast.Ast.str_item -> Parsetree.toplevel_phrase
+  (** Converts a camlp4 toplevel phrase into a standard OCaml toplevel
+      phrase. *)