1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
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15 include "ground/notation/functions/droppreds_2.ma".
16 include "ground/lib/stream_tls.ma".
17 include "ground/relocation/gr_tl.ma".
19 (* ITERATED TAIL FOR GENERIC RELOCATION MAPS ********************************)
22 definition gr_tls (n) (f:gr_map) ≝ ⫰*[n]f.
25 "iterated tail (generic relocation maps)"
26 'DropPreds n f = (gr_tls n f).
28 (* Basic constructions (specific) *******************************************)
31 lemma gr_tls_zero (f): f = ⫱*[𝟎] f.
35 lemma gr_tls_tl (n) (f): ⫱⫱*[n] f = ⫱*[n] ⫱f.
36 /2 width=1 by stream_tls_tl/ qed.
39 lemma gr_tls_succ (n) (f): ⫱⫱*[n] f = ⫱*[↑n] f.
40 /2 width=1 by stream_tls_succ/ qed.
43 lemma gr_tls_swap (n) (f): ⫱*[n] ⫱f = ⫱*[↑n] f.