Unify location handling of error functions.

In some cases prior to this patch, there were two cases for the same
error function, one taking a location, the other not.

We unify them by using an option parameter, in the line with recent
changes in warnings and feedback.

This implies a bit of clean up in some places, but more importantly, is
the preparation for subsequent patches making `Loc.location` opaque,
change that could be use to improve modularity and allow a more
functional implementation strategy --- for example --- of the
beautifier.

5 files changed, 15 insertions, 12 deletions

diff --git a/lib/cErrors.ml b/lib/cErrors.ml
index 1459141d1..c5f262373 100644
--- a/lib/cErrors.ml
+++ b/lib/cErrors.ml
@@ -26,9 +26,8 @@ let _ =
 let make_anomaly ?label pp =
   Anomaly (label, pp)
 
-let anomaly ?loc ?label pp = match loc with
-  | None -> raise (Anomaly (label, pp))
-  | Some loc -> Loc.raise loc (Anomaly (label, pp))
+let anomaly ?loc ?label pp =
+  Loc.raise ?loc (Anomaly (label, pp))
 
 let is_anomaly = function
 | Anomaly _ -> true
@@ -43,8 +42,8 @@ let alreadydeclared pps = raise (AlreadyDeclared(pps))
 
 let todo s = prerr_string ("TODO: "^s^"\n")
 
-let user_err_loc (loc,s,strm) = Loc.raise loc (UserError (s,strm))
-let invalid_arg_loc (loc,s) = Loc.raise loc (Invalid_argument s)
+let user_err    ?loc s strm = Loc.raise ?loc (UserError (s,strm))
+let invalid_arg ?loc s   = Loc.raise ?loc (Invalid_argument s)
 
 exception Timeout
 exception Drop
diff --git a/lib/cErrors.mli b/lib/cErrors.mli
index e5dad93fd..291c39b84 100644
--- a/lib/cErrors.mli
+++ b/lib/cErrors.mli
@@ -36,12 +36,13 @@ val is_anomaly : exn -> bool
 exception UserError of string * std_ppcmds
 val error : string -> 'a
 val errorlabstrm : string -> std_ppcmds -> 'a
-val user_err_loc : Loc.t * string * std_ppcmds -> 'a
+
+val user_err     : ?loc:Loc.t -> string -> std_ppcmds -> 'a
 
 exception AlreadyDeclared of std_ppcmds
 val alreadydeclared : std_ppcmds -> 'a
 
-val invalid_arg_loc : Loc.t * string -> 'a
+val invalid_arg : ?loc:Loc.t -> string -> 'a
 
 (** [todo] is for running of an incomplete code its implementation is
    "do nothing" (or print a message), but this function should not be
diff --git a/lib/cWarnings.ml b/lib/cWarnings.ml
index 78fa84f33..f36c7ad80 100644
--- a/lib/cWarnings.ml
+++ b/lib/cWarnings.ml
@@ -45,7 +45,7 @@ let create ~name ~category ?(default=Enabled) pp =
            | Disabled -> ()
            | AsError ->
               let loc = Option.default !current_loc loc in
-              CErrors.user_err_loc (loc,"_",pp x)
+              CErrors.user_err ~loc "_" (pp x)
            | Enabled ->
               let msg =
                 pp x ++ spc () ++ str "[" ++ str name ++ str "," ++
diff --git a/lib/loc.ml b/lib/loc.ml
index 0f9864a9a..e373a760c 100644
--- a/lib/loc.ml
+++ b/lib/loc.ml
@@ -71,6 +71,9 @@ let add_loc e loc = Exninfo.add e location loc
 
 let get_loc e = Exninfo.get e location
 
-let raise loc e =
-  let info = Exninfo.add Exninfo.null location loc in
-  Exninfo.iraise (e, info)
+let raise ?loc e =
+  match loc with
+  | None     -> raise e
+  | Some loc ->
+    let info = Exninfo.add Exninfo.null location loc in
+    Exninfo.iraise (e, info)
diff --git a/lib/loc.mli b/lib/loc.mli
index c08e097a8..bb88f8642 100644
--- a/lib/loc.mli
+++ b/lib/loc.mli
@@ -51,7 +51,7 @@ val add_loc : Exninfo.info -> t -> Exninfo.info
 val get_loc : Exninfo.info -> t option
 (** Retrieving the optional location of an exception *)
 
-val raise : t -> exn -> 'a
+val raise : ?loc:t -> exn -> 'a
 (** [raise loc e] is the same as [Pervasives.raise (add_loc e loc)]. *)
 
 (** {5 Location utilities} *)