A new infrastructure for warnings.

On the user side, coqtop and coqc take a list of warning names or categories
after -w. No prefix means activate the warning, a "-" prefix means deactivate
it, and "+" means turn the warning into an error. Special categories include
"all", and "default" which contains the warnings enabled by default.

We also provide a vernacular Set Warnings which takes the same flags as argument.

Note that coqc now prints warnings.

The name and category of a warning are printed with the warning itself.

On the developer side, Feedback.msg_warning is still accessible, but the
recommended way to print a warning is in two steps:

1) create it by:

let warn_my_warning =
  CWarnings.create ~name:"my-warning" ~category:"my-category"
    (fun args -> Pp.strbrk ...)

2) print it by:

warn_my_warning args

1 files changed, 19 insertions, 0 deletions

diff --git a/lib/pp.ml b/lib/pp.ml
index d07f01b90..f1eb4c059 100644
--- a/lib/pp.ml
+++ b/lib/pp.ml
@@ -197,6 +197,25 @@ let strbrk s =
     else if p = n then [] else [str (String.sub s p (n-p))]
   in List.fold_left (++) Glue.empty (aux 0 0)
 
+let pr_loc_pos loc =
+  if Loc.is_ghost loc then (str"<unknown>")
+  else
+    let loc = Loc.unloc loc in
+    int (fst loc) ++ str"-" ++ int (snd loc)
+
+let pr_loc loc =
+  if Loc.is_ghost loc then str"<unknown>"
+  else
+    let fname = loc.Loc.fname in
+    if CString.equal fname "" then
+      Loc.(str"Toplevel input, characters " ++ int loc.bp ++
+	   str"-" ++ int loc.ep ++ str":" ++ fnl ())
+    else
+      Loc.(str"File " ++ str "\"" ++ str fname ++ str "\"" ++
+	   str", line " ++ int loc.line_nb ++ str", characters " ++
+	   int (loc.bp-loc.bol_pos) ++ str"-" ++ int (loc.ep-loc.bol_pos) ++
+	   str":" ++ fnl())
+
 let ismt = is_empty
 
 (* boxing commands *)