Improving checks about the list separator in tactic notations.

In Tactic Notation and TACTIC EXTEND, when an argument not ending with
"_list_sep" was given with a separator, the separator was silently
ignored.

Now:
- we take it into account if it is a list (i.e. ending with "_list"), as if
  "_list_sep" was given, since after all, the "_sep" is useless in the name.
- we fail if there is a separator but it is not a "_list" or "_list_sep".

2 files changed, 24 insertions, 7 deletions

diff --git a/grammar/q_util.mlp b/grammar/q_util.mlp
index 536ee7ca5..c2d767396 100644
--- a/grammar/q_util.mlp
+++ b/grammar/q_util.mlp
@@ -94,10 +94,14 @@ let coincide s pat off =
   done;
   !break
 
+let check_separator sep =
+  if sep <> "" then failwith "Separator is only for arguments with suffix _list_sep."
+
 let rec parse_user_entry s sep =
   let l = String.length s in
   if l > 8 && coincide s "ne_" 0 && coincide s "_list" (l - 5) then
     let entry = parse_user_entry (String.sub s 3 (l-8)) "" in
+    check_separator sep;
     Ulist1 entry
   else if l > 12 && coincide s "ne_" 0 &&
                    coincide s "_list_sep" (l-9) then
@@ -105,16 +109,20 @@ let rec parse_user_entry s sep =
     Ulist1sep (entry, sep)
   else if l > 5 && coincide s "_list" (l-5) then
     let entry = parse_user_entry (String.sub s 0 (l-5)) "" in
+    check_separator sep;
     Ulist0 entry
   else if l > 9 && coincide s "_list_sep" (l-9) then
     let entry = parse_user_entry (String.sub s 0 (l-9)) "" in
     Ulist0sep (entry, sep)
   else if l > 4 && coincide s "_opt" (l-4) then
     let entry = parse_user_entry (String.sub s 0 (l-4)) "" in
+    check_separator sep;
     Uopt entry
   else if l = 7 && coincide s "tactic" 0 && '5' >= s.[6] && s.[6] >= '0' then
     let n = Char.code s.[6] - 48 in
+    check_separator sep;
     Uentryl ("tactic", n)
   else
     let s = match s with "hyp" -> "var" | _ -> s in
+    check_separator sep;
     Uentry s
diff --git a/plugins/ltac/tacentries.ml b/plugins/ltac/tacentries.ml
index 0bf6e3d15..ee84be541 100644
--- a/plugins/ltac/tacentries.ml
+++ b/plugins/ltac/tacentries.ml
@@ -63,28 +63,37 @@ let get_separator = function
 | None -> user_err Pp.(str "Missing separator.")
 | Some sep -> sep
 
-let rec parse_user_entry s sep =
+let check_separator ?loc = function
+| None -> ()
+| Some _ -> user_err ?loc (str "Separator is only for arguments with suffix _list_sep.")
+
+let rec parse_user_entry ?loc s sep =
   let l = String.length s in
   if l > 8 && coincide s "ne_" 0 && coincide s "_list" (l - 5) then
-    let entry = parse_user_entry (String.sub s 3 (l-8)) None in
+    let entry = parse_user_entry ?loc (String.sub s 3 (l-8)) None in
+    check_separator ?loc sep;
     Ulist1 entry
   else if l > 12 && coincide s "ne_" 0 &&
                    coincide s "_list_sep" (l-9) then
-    let entry = parse_user_entry (String.sub s 3 (l-12)) None in
+    let entry = parse_user_entry ?loc (String.sub s 3 (l-12)) None in
     Ulist1sep (entry, get_separator sep)
   else if l > 5 && coincide s "_list" (l-5) then
-    let entry = parse_user_entry (String.sub s 0 (l-5)) None in
+    let entry = parse_user_entry ?loc (String.sub s 0 (l-5)) None in
+    check_separator ?loc sep;
     Ulist0 entry
   else if l > 9 && coincide s "_list_sep" (l-9) then
-    let entry = parse_user_entry (String.sub s 0 (l-9)) None in
+    let entry = parse_user_entry ?loc (String.sub s 0 (l-9)) None in
     Ulist0sep (entry, get_separator sep)
   else if l > 4 && coincide s "_opt" (l-4) then
-    let entry = parse_user_entry (String.sub s 0 (l-4)) None in
+    let entry = parse_user_entry ?loc (String.sub s 0 (l-4)) None in
+    check_separator ?loc sep;
     Uopt entry
   else if Int.equal l 7 && coincide s "tactic" 0 && '5' >= s.[6] && s.[6] >= '0' then
     let n = Char.code s.[6] - 48 in
+    check_separator ?loc sep;
     Uentryl ("tactic", n)
   else
+    let _ = check_separator ?loc sep in
     Uentry s
 
 let interp_entry_name interp symb =
@@ -203,7 +212,7 @@ let register_tactic_notation_entry name entry =
 let interp_prod_item = function
   | TacTerm s -> TacTerm s
   | TacNonTerm (loc, ((nt, sep), ido)) ->
-    let symbol = parse_user_entry nt sep in
+    let symbol = parse_user_entry ?loc nt sep in
     let interp s = function
     | None ->
       if String.Map.mem s !entry_names then String.Map.find s !entry_names