From 585b70958440a8ae155e9ef8281099b66a9ba836 Mon Sep 17 00:00:00 2001
From: Claudio Sacerdoti Coen <claudio.sacerdoticoen@unibo.it>
Date: Wed, 7 Dec 2005 19:00:25 +0000
Subject: [PATCH] More compact disambiguation errors.

---
 helm/matita/matitaExcPp.ml | 47 ++++++++++++++++++++++++--------------
 1 file changed, 30 insertions(+), 17 deletions(-)

diff --git a/helm/matita/matitaExcPp.ml b/helm/matita/matitaExcPp.ml
index c09b22fdd..29f08d514 100644
--- a/helm/matita/matitaExcPp.ml
+++ b/helm/matita/matitaExcPp.ml
@@ -64,23 +64,27 @@ let rec to_string =
   | LibrarySync.AlreadyDefined s -> 
      None, "Already defined: " ^ UriManager.string_of_uri s
   | MatitaDisambiguator.DisambiguationError (offset,errorll) ->
-     let rec aux n =
+     let rec aux n ?(dummy=false) (prev_msg,phases) =
       function
-         [] -> ""
+         [] -> []
        | phase::tl ->
-          aux (n+1) tl ^
-           "***** Errors obtained during phase " ^ string_of_int n ^": *****\n"^
-            String.concat "\n\n"
-             (List.map (fun (floc,msg) ->
-               let loc_descr =
-                match floc with
-                   None -> ""
-                 | Some floc ->
-                    let (x, y) = HExtlib.loc_of_floc floc in
-                     sprintf " at %d-%d" (x+offset) (y+offset)
-               in
-                "*Error" ^ loc_descr ^ ": " ^ Lazy.force msg) phase) ^
-            "\n\n\n" in
+          let msg =
+           String.concat "\n\n\n"
+            (List.map (fun (floc,msg) ->
+              let loc_descr =
+               match floc with
+                  None -> ""
+                | Some floc ->
+                   let (x, y) = HExtlib.loc_of_floc floc in
+                    sprintf " at %d-%d" (x+offset) (y+offset)
+              in
+               "*Error" ^ loc_descr ^ ": " ^ Lazy.force msg) phase)
+          in
+           if msg = prev_msg then
+            aux (n+1) (msg,phases@[n]) tl
+           else
+            (if not dummy then [prev_msg,phases] else []) @
+             (aux (n+1) (msg,[n]) tl) in
      let loc =
       match errorll with
          ((Some floc,_)::_)::_ ->
@@ -92,10 +96,19 @@ let rec to_string =
            {flocb with Lexing.pos_cnum = x}, {floce with Lexing.pos_cnum = y}
           in
            Some floc
-       | _ -> None
+       | _ -> None in
+     let rec explain =
+      function
+         [] -> ""
+       | (msg,phases)::tl ->
+           explain tl ^
+           "***** Errors obtained during phase" ^
+            (if phases = [] then " " else "s ") ^
+            String.concat "," (List.map string_of_int phases) ^": *****\n"^
+            msg ^ "\n\n"
      in
       loc,
        "********** DISAMBIGUATION ERRORS: **********\n" ^
-        aux 1 errorll
+        explain (aux 1 ~dummy:true ("",[]) errorll)
   | exn -> None, "Uncaught exception: " ^ Printexc.to_string exn
 
-- 
2.39.2