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/downharpoonright_2.ma".
16 include "ground/lib/list.ma".
18 (* TAIL FOR LISTS ***********************************************************)
20 definition list_tl (A:Type[0]): list A → list A.
21 #A * [ @(ⓔ) | #_ #t @t ]
26 'DownHarpoonRight A t = (list_tl A t).
28 (* Basic constructions ******************************************************)
30 lemma list_tl_empty (A):
34 lemma list_tl_lcons (A) (a) (t):