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+(* -*- coq-prog-args: ("-emacs" "-compat" "8.4") -*- *)
+(*Suppose a user wants to declare a new list-like notation with support for singletons in both 8.4 and 8.5.  If they use*)
+Require Import Coq.Lists.List.
+Require Import Coq.Vectors.Vector.
+Import ListNotations.
+Import VectorNotations.
+Set Implicit Arguments.
+Inductive mylist T := mynil | mycons (_ : T) (_ : mylist T).
+Arguments mynil {_}, _.
+
+Delimit Scope mylist_scope with mylist.
+Bind Scope mylist_scope with mylist.
+Delimit Scope vector_scope with vector.
+
+Notation " [ ] " := mynil (format "[ ]") : mylist_scope.
+Notation " [ x ] " := (mycons x mynil) : mylist_scope.
+Notation " [ x ; .. ; y ] " := (mycons x .. (mycons y mynil) ..) : mylist_scope.
+
+(** All of these should work fine in -compat 8.4 mode, just as they do in Coq 8.4.  There needs to be a way to specify notations above so that all of these [Check]s go through in both 8.4 and 8.5 *)
+Check [ ]%mylist : mylist _.
+Check [ ]%list : list _.
+Check []%vector : Vector.t _ _.
+Check [ _ ]%mylist : mylist _.
+Check [ _ ]%list : list _.
+Check [ _ ]%vector : Vector.t _ _.
+Check [ _ ; _ ]%list : list _.
+Check [ _ ; _ ]%vector : Vector.t _ _.
+Check [ _ ; _ ]%mylist : mylist _.
+Check [ _ ; _ ; _ ]%list : list _.
+Check [ _ ; _ ; _ ]%vector : Vector.t _ _.
+Check [ _ ; _ ; _ ]%mylist : mylist _.
+Check [ _ ; _ ; _ ; _ ]%list : list _.
+Check [ _ ; _ ; _ ; _ ]%vector : Vector.t _ _.
+Check [ _ ; _ ; _ ; _ ]%mylist : mylist _.
+
+(** Now check that we can add and then remove notations from the parser *)
+(* We should be able to stick some vernacular here to remove [] from the parser *)
+Fail Remove Notation "[]".
+Goal True.
+  (* This should not be a syntax error; before moving this file to closed, uncomment this line. *)
+  (* idtac; []. *)
+  constructor.
+Qed.
+
+Check { _ : _ & _ }.
+Reserved Infix "&" (at level 0).
+Fail Remove Infix "&".
+(* Check { _ : _ & _ }. *)