+++ /dev/null
-(**************************************************************************)
-(* ___ *)
-(* ||M|| *)
-(* ||A|| A project by Andrea Asperti *)
-(* ||T|| *)
-(* ||I|| Developers: *)
-(* ||T|| The HELM team. *)
-(* ||A|| http://helm.cs.unibo.it *)
-(* \ / *)
-(* \ / This file is distributed under the terms of the *)
-(* v GNU General Public License Version 2 *)
-(* *)
-(**************************************************************************)
-
-include "delayed_updating/syntax/path.ma".
-include "delayed_updating/notation/functions/power_2.ma".
-include "ground/arith/nat_succ_iter.ma".
-
-(* *)
-
-definition labels (l) (n:nat): path ā
- ((list_lcons ? l)^n) (š).
-
-interpretation
- "labels (path)"
- 'Power l n = (labels l n).
-
-(* Basic constructions ******************************************************)
-
-lemma labels_unfold (l) (n):
- ((list_lcons ? l)^n) (š) = lāān.
-// qed.
-
-lemma labels_zero (l):
- (š) = lāāš.
-// qed.
-
-lemma labels_succ (l) (n):
- (lāān)āl = lāā(ān).
-#l #n
-<labels_unfold <labels_unfold <niter_succ //
-qed.
-
-(* Basic inversions *********************************************************)
-
-lemma eq_inv_empty_labels (l) (n):
- (š) = lāān ā š = n.
-#l #n @(nat_ind_succ ā¦ n) -n //
-#n #_ <labels_succ #H0 destruct
-qed-.