-lemma cpr_inv_cast1: ∀h,G,L,V1,U1,U2. ⦃G, L⦄ ⊢ ⓝ V1. U1 ➡[h] U2 → (
- ∃∃V2,T2. ⦃G, L⦄ ⊢ V1 ➡[h] V2 & ⦃G, L⦄ ⊢ U1 ➡[h] T2 &
- U2 = ⓝV2.T2
- ) ∨ ⦃G, L⦄ ⊢ U1 ➡[h] U2.
+lemma cpr_inv_cast1: ∀h,G,L,V1,U1,U2. ⦃G, L⦄ ⊢ ⓝ V1.U1 ➡[h] U2 →
+ â\88¨â\88¨ â\88\83â\88\83V2,T2. â¦\83G, Lâ¦\84 â\8a¢ V1 â\9e¡[h] V2 & â¦\83G, Lâ¦\84 â\8a¢ U1 â\9e¡[h] T2 &
+ U2 = ⓝV2.T2
+ | ⦃G, L⦄ ⊢ U1 ➡[h] U2.