Merge PR #6167: Fixing factorization of recursive notations with an atomic separator

2 files changed, 14 insertions, 3 deletions

diff --git a/parsing/egramcoq.ml b/parsing/egramcoq.ml
index 7f50fd22a..2cb7da569 100644
--- a/parsing/egramcoq.ml
+++ b/parsing/egramcoq.ml
@@ -259,9 +259,11 @@ let is_binder_level from e = match e with
 | (NumLevel 200, (BorderProd (Right, _) | InternalProd)) -> from = 200
 | _ -> false
 
-let make_sep_rules tkl =
-  let rec mkrule : Tok.t list -> unit rules = function
-  | [] -> Rules ({ norec_rule = Stop }, ignore)
+let make_sep_rules = function
+  | [tk] -> Atoken tk
+  | tkl ->
+  let rec mkrule : Tok.t list -> string rules = function
+  | [] -> Rules ({ norec_rule = Stop }, fun _ -> (* dropped anyway: *) "")
   | tkn :: rem ->
     let Rules ({ norec_rule = r }, f) = mkrule rem in
     let r = { norec_rule = Next (r, Atoken tkn) } in
diff --git a/test-suite/success/Notations2.v b/test-suite/success/Notations2.v
index e86b3edb8..2655b651a 100644
--- a/test-suite/success/Notations2.v
+++ b/test-suite/success/Notations2.v
@@ -96,3 +96,12 @@ Check fun A (x :prod' bool A) => match x with ##### 0 _ y 0%bool => 2 | _ => 1 e
 
 Notation "'FUNNAT' i => t" := (fun i : nat => i = t) (at level 200).
 Notation "'Funnat' i => t" := (FUNNAT i => t + i%nat) (at level 200).
+
+(* 11. Notations with needed factorization of a recursive pattern *)
+(* See https://github.com/coq/coq/issues/6078#issuecomment-342287412 *)
+Module A.
+Notation "[:: x1 ; .. ; xn & s ]" := (cons x1 .. (cons xn s) ..).
+Notation "[:: x1 ; .. ; xn ]" := (cons x1 .. (cons xn nil) ..).
+Check [:: 1 ; 2 ; 3 ].
+Check [:: 1 ; 2 ; 3 & nil ]. (* was failing *)
+End A.