definition tc_dedropable_sn: predicate (relation3 lenv term term) ≝
λR. ∀b,f,L1,K1. ⬇*[b, f] L1 ≡ K1 →
- â\88\80K2,T. K1 ⦻**[R, T] K2 → ∀U. ⬆*[f] T ≡ U →
- â\88\83â\88\83L2. L1 ⦻**[R, U] L2 & ⬇*[b, f] L2 ≡ K2 & L1 ≡[f] L2.
+ â\88\80K2,T. K1 ⪤**[R, T] K2 → ∀U. ⬆*[f] T ≡ U →
+ â\88\83â\88\83L2. L1 ⪤**[R, U] L2 & ⬇*[b, f] L2 ≡ K2 & L1 ≡[f] L2.
definition tc_dropable_sn: predicate (relation3 lenv term term) ≝
λR. ∀b,f,L1,K1. ⬇*[b, f] L1 ≡ K1 → 𝐔⦃f⦄ →
- â\88\80L2,U. L1 ⦻**[R, U] L2 → ∀T. ⬆*[f] T ≡ U →
- â\88\83â\88\83K2. K1 ⦻**[R, T] K2 & ⬇*[b, f] L2 ≡ K2.
+ â\88\80L2,U. L1 ⪤**[R, U] L2 → ∀T. ⬆*[f] T ≡ U →
+ â\88\83â\88\83K2. K1 ⪤**[R, T] K2 & ⬇*[b, f] L2 ≡ K2.
definition tc_dropable_dx: predicate (relation3 lenv term term) ≝
- λR. â\88\80L1,L2,U. L1 ⦻**[R, U] L2 →
+ λR. â\88\80L1,L2,U. L1 ⪤**[R, U] L2 →
∀b,f,K2. ⬇*[b, f] L2 ≡ K2 → 𝐔⦃f⦄ → ∀T. ⬆*[f] T ≡ U →
- â\88\83â\88\83K1. â¬\87*[b, f] L1 â\89¡ K1 & K1 ⦻**[R, T] K2.
+ â\88\83â\88\83K1. â¬\87*[b, f] L1 â\89¡ K1 & K1 ⪤**[R, T] K2.
(* Properties with generic slicing for local environments *******************)