src/FOL/hypsubstdata.ML

proper subgoal addressing via SUBGOAL/CSUBGOAL -- assuming these tactics did not handle Subscript in any special way;
tuned;

(** Applying HypsubstFun to generate hyp_subst_tac **)
structure Hypsubst_Data =
struct
  structure Simplifier = Simplifier
  val dest_eq = FOLogic.dest_eq
  val dest_Trueprop = FOLogic.dest_Trueprop
  val dest_imp = FOLogic.dest_imp
  val eq_reflection = @{thm eq_reflection}
  val rev_eq_reflection = @{thm meta_eq_to_obj_eq}
  val imp_intr = @{thm impI}
  val rev_mp = @{thm rev_mp}
  val subst = @{thm subst}
  val sym = @{thm sym}
  val thin_refl = @{thm thin_refl}
end;

structure Hypsubst = HypsubstFun(Hypsubst_Data);
open Hypsubst;