(* Basic eliminators ********************************************************)
-theorem fsb_ind_alt: ∀h,g. ∀R: relation3 …. (
- ∀G1,L1,T1. (
- ∀G2,L2,T2. ⦃G1, L1, T1⦄≽ [h, g] ⦃G2, L2, T2⦄ →
- (|G1| = |G2| → |L1| = |L2| → T1 = T2 → ⊥) → ⦃G2, L2⦄ ⊢ ⦥[h,g] T2
- ) → (
- ∀G2,L2,T2. ⦃G1, L1, T1⦄≽ [h, g] ⦃G2, L2, T2⦄ →
- (|G1| = |G2| → |L1| = |L2| → T1 = T2 → ⊥) → R G2 L2 T2
- ) → R G1 L1 T1
- ) →
- ∀G,L,T. ⦃G, L⦄ ⊢ ⦥[h, g] T → R G L T.
-#h #g #R #IH #G #L #T #H elim H -G -L -T /5 width=1 by fpb_fpbc/
+lemma fsb_ind_alt: ∀h,g. ∀R: relation3 …. (
+ ∀G1,L1,T1. ⦃G1, L1⦄ ⊢ ⦥[h,g] T1 → (
+ ∀G2,L2,T2. ⦃G1, L1, T1⦄ ≻[h, g] ⦃G2, L2, T2⦄ → R G2 L2 T2
+ ) → R G1 L1 T1
+ ) →
+ ∀G,L,T. ⦃G, L⦄ ⊢ ⦥[h, g] T → R G L T.
+#h #g #R #IH #G #L #T #H elim H -G -L -T
+/4 width=1 by fsb_intro/
qed-.
(* Basic inversion lemmas ***************************************************)