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 "apps_2/notation/models/ringeq_5.ma".
16 include "apps_2/models/li.ma".
17 include "static_2/syntax/genv.ma".
19 (* DENOTATIONAL EQUIVALENCE ************************************************)
21 definition deq (M): relation4 genv lenv term term ≝
22 λG,L,T1,T2. ∀gv,lv. lv ϵ ⟦L⟧[gv] → ⟦T1⟧[gv,lv] ≗{M} ⟦T2⟧[gv,lv].
24 interpretation "denotational equivalence (model)"
25 'RingEq M G L T1 T2 = (deq M G L T1 T2).
27 (* Basic properties *********************************************************)
29 lemma deq_refl (M): is_model M →
30 ∀G,L. reflexive … (deq M G L).
31 /2 width=1 by mr/ qed.
33 lemma veq_sym: ∀M. symmetric … (veq M).
36 theorem veq_trans: ∀M. transitive … (veq M).