matita/matita/contribs/lambdadelta/basic_2/static/ffdeq.ma

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  14
  15 include "basic_2/notation/relations/stareqsn_8.ma".
  16 include "basic_2/syntax/genv.ma".
  17 include "basic_2/static/lfdeq.ma".
  18
  19 (* DEGREE-BASED EQUIVALENCE FOR CLOSURES ON REFERRED ENTRIES ****************)
  20
  21 inductive ffdeq (h) (o) (G) (L1) (T): relation3 genv lenv term ≝
  22 | ffdeq_intro: ∀L2. L1 ≛[h, o, T] L2 → ffdeq h o G L1 T G L2 T
  23 .
  24
  25 interpretation
  26    "degree-based equivalence on referred entries (closure)"
  27    'StarEqSn h o G1 L1 T1 G2 L2 T2 = (ffdeq h o G1 L1 T1 G2 L2 T2).
  28
  29 (* Basic inversion lemmas ***************************************************)
  30
  31 lemma ffdeq_inv_gen: ∀h,o,G1,G2,L1,L2,T1,T2. ⦃G1, L1, T1⦄ ≛[h, o] ⦃G2, L2, T2⦄ →
  32                      ∧∧ G1 = G2 & L1 ≛[h, o, T1] L2 & T1 = T2.
  33 #h #o #G1 #G2 #L1 #L2 #T1 #T2 * -G2 -L2 -T2 /2 width=1 by and3_intro/
  34 qed-.
  35
  36 (* Basic_2A1: removed theorems 6:
  37               fleq_refl fleq_sym fleq_inv_gen
  38               fleq_trans fleq_canc_sn fleq_canc_dx
  39 *)