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 *)
13 (**************************************************************************)
15 include "static_2/syntax/lenv.ma".
17 (* SHIFT FOR RESTRICTED CLOSURES ********************************************)
19 rec definition shift L T on L ≝ match L with
21 | LBind L I ⇒ match I with
22 [ BUnit _ ⇒ shift L (-ⓛ⋆0.T)
23 | BPair I V ⇒ shift L (-ⓑ{I}V.T)
27 interpretation "shift (restricted closure)" 'plus L T = (shift L T).
29 (* Basic properties *********************************************************)
31 lemma shift_atom: ∀T. ⋆ + T = T.
34 lemma shift_unit: ∀I,L,T. L.ⓤ{I}+T = L+(-ⓛ⋆0.T).
37 lemma shift_pair: ∀I,L,V,T. (L.ⓑ{I}V)+T = L+(-ⓑ{I}V.T).