Variable.focus etc.: optional bindings provided by user;
Subgoal.focus command: more careful treatment of user-provided bindings;
(* Title: Pure/ML-Systems/share_common_data_polyml-5.3.0.ML
Dummy for Poly/ML 5.3.0, which cannot share the massive heap of HOL
anymore.
*)
structure PolyML =
struct
open PolyML;
fun shareCommonData _ = ();
end;