(* Properties on stratified static type assignment **************************)
lemma lsubsv_ssta_trans: ∀h,g,L2,T,U2,l. ⦃h, L2⦄ ⊢ T •[g] ⦃l, U2⦄ →
- ∀L1. h ⊢ L1 ⊩:⊑[g] L2 →
+ ∀L1. h ⊢ L1 ¡⊑[g] L2 →
∃∃U1. ⦃h, L1⦄ ⊢ T •[g] ⦃l, U1⦄ & L1 ⊢ U1 ⬌* U2.
/3 width=3 by lsubsv_fwd_lsubss, lsubss_ssta_trans/
qed-.