(* Advanced eliminators *****************************************************)
lemma tc_lfxs_ind_sn: ∀R. c_reflexive … R →
- ∀L1,T. ∀R0:predicate …. R0 L1 →
- (∀L,L2. L1 ⪤**[R, T] L → L ⪤*[R, T] L2 → R0 L → R0 L2) →
- ∀L2. L1 ⪤**[R, T] L2 → R0 L2.
-#R #HR #L1 #T #R0 #HL1 #IHL1 #L2 #HL12
+ ∀L1,T. ∀Q:predicate …. Q L1 →
+ (∀L,L2. L1 ⪤**[R, T] L → L ⪤*[R, T] L2 → Q L → Q L2) →
+ ∀L2. L1 ⪤**[R, T] L2 → Q L2.
+#R #HR #L1 #T #Q #HL1 #IHL1 #L2 #HL12
@(TC_star_ind … HL1 IHL1 … HL12) /2 width=1 by lfxs_refl/
qed-.
lemma tc_lfxs_ind_dx: ∀R. c_reflexive … R →
- ∀L2,T. ∀R0:predicate …. R0 L2 →
- (∀L1,L. L1 ⪤*[R, T] L → L ⪤**[R, T] L2 → R0 L → R0 L1) →
- ∀L1. L1 ⪤**[R, T] L2 → R0 L1.
-#R #HR #L2 #R0 #HL2 #IHL2 #L1 #HL12
+ ∀L2,T. ∀Q:predicate …. Q L2 →
+ (∀L1,L. L1 ⪤*[R, T] L → L ⪤**[R, T] L2 → Q L → Q L1) →
+ ∀L1. L1 ⪤**[R, T] L2 → Q L1.
+#R #HR #L2 #Q #HL2 #IHL2 #L1 #HL12
@(TC_star_ind_dx … HL2 IHL2 … HL12) /2 width=4 by lfxs_refl/
qed-.