(* RELOCATION MAP ***********************************************************)
-rec definition tls (f:rtmap) (n:nat) on n: rtmap ≝ match n with
-[ O ⇒ f | S m ⇒ ⫱(tls f m) ].
+definition tls (f:rtmap) (n:nat) ≝ tl^n f.
interpretation "tls (rtmap)" 'DropPreds n f = (tls f n).
(* Basic properties *********************************************************)
-lemma tls_O: ∀f. f = ⫱*[0] f.
+lemma tls_O: ∀f. f = ⫱*[𝟎] f.
// qed.
lemma tls_S: ∀f,n. ⫱ ⫱*[n] f = ⫱*[↑n] f.
-// qed.
+#f #n @(niter_succ … tl)
+qed.
lemma tls_eq_repl: ∀n. eq_repl (λf1,f2. ⫱*[n] f1 ≡ ⫱*[n] f2).
-#n elim n -n /3 width=1 by tl_eq_repl/
+#n @(nat_ind_succ … n) -n /3 width=1 by tl_eq_repl/
qed.
(* Advanced properties ******************************************************)
-lemma tls_xn: ∀n,f. ⫱*[n] ⫱f = ⫱*[↑n] f.
-#n elim n -n //
+lemma tls_swap (n) (f): ⫱ ⫱*[n] f = ⫱*[n] ⫱f.
+#f #n @(niter_appl … tl)
qed.
+lemma tls_xn: ∀n,f. ⫱*[n] ⫱f = ⫱*[↑n] f.
+// qed.
+
(* Properties with pushs ****************************************************)
lemma tls_pushs: ∀n,f. f = ⫱*[n] ⫯*[n] f.
-#n elim n -n //
-#n #IH #f <tls_xn //
+#n @(nat_ind_succ … n) -n //
+#n #IH #f <tls_xn <pushs_S <tl_push_rew //
qed.