Goal:
    A : Type  P : A → Type  a : A  X : All P [a]
  ============================
   (let H := CoreTactics.block in let H0 := CoreTactics.block in P a)


DEBUG:Going to execute:
try simpl in H; DepElim.simplify_equations_in H
DEBUG LTAC Evaluated term: (let H := CoreTactics.block in
                            let H0 := CoreTactics.block in P a)