Natools

   overriding procedure Append_Atom
     (Output : in out Reference; Data : in Atom);
   overriding procedure Close_List (Output : in out Reference);

   function Duplicate (Cache : Reference) return Reference;
      --  Create a new copy of the S-expression held in Cache and return it

   function Move (Source : in out S_Expressions.Descriptor'Class)
     return Reference;
      --  Build a new cache by (destructively) reading Original


   type Cursor is new Lockable.Descriptor and Replayable.Descriptor
     with private;
   pragma Preelaborable_Initialization (Cursor);

   overriding function Current_Event (Object : in Cursor) return Events.Event;
   overriding function Current_Atom (Object : in Cursor) return Atom;

      State : in out Lockable.Lock_State;
      Finish : in Boolean := True);

   overriding function Duplicate (Object : Cursor) return Cursor;

   function First (Cache : Reference'Class) return Cursor;
      --  Create a new Cursor pointing at the beginning of Cache

   function Move (Source : in out S_Expressions.Descriptor'Class) return Cursor
     is (Move (Source).First);
      --  Return a cursor holding a copy of Original (which is
      --  destructively read)

private

   type Atom_Access is access Atom;
   for Atom_Access'Storage_Pool use Atom_Pool;
   procedure Unchecked_Free is new Ada.Unchecked_Deallocation
     (Atom, Atom_Access);