matita/matita/contribs/lambdadelta/apps_2/models/deq.ma

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  14
  15 include "apps_2/notation/models/ringeq_5.ma".
  16 include "apps_2/models/model_gi.ma".
  17 include "apps_2/models/model_li.ma".
  18 include "apps_2/models/model_props.ma".
  19
  20 (* DENOTATIONAL EQUIVALENCE  ************************************************)
  21
  22 definition deq (M): relation4 genv lenv term term ≝
  23                     λG,L,T1,T2. ∀gv,lv. lv ϵ ⟦L⟧[gv] → ⟦T1⟧[gv, lv] ≗{M} ⟦T2⟧[gv, lv].
  24
  25 interpretation "denotational equivalence (model)"
  26    'RingEq M G L T1 T2 = (deq M G L T1 T2).
  27
  28 (* Basic properties *********************************************************)
  29
  30 lemma deq_refl (M): is_model M →
  31                     ∀G,L. reflexive … (deq M G L).
  32 /2 width=1 by mq/ qed.
  33 (*
  34 lemma veq_sym: ∀M. symmetric … (veq M).
  35 // qed-.
  36
  37 theorem veq_trans: ∀M. transitive … (veq M).
  38 // qed-.
  39 *)