matita/matita/contribs/lambdadelta/basic_2/rt_transition/cnu.ma

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  14
  15 include "basic_2/notation/relations/preditnormal_4.ma".
  16 include "static_2/syntax/tueq.ma".
  17 include "basic_2/rt_transition/cpm.ma".
  18
  19 (* NORMAL TERMS FOR T-UNUNBOUND RT-TRANSITION *******************************)
  20
  21 definition cnu (h) (G) (L): predicate term ≝
  22            λT1. ∀n,T2. ⦃G,L⦄ ⊢ T1 ➡[n,h] T2 → T1 ≅ T2.
  23
  24 interpretation
  25    "normality for t-unbound context-sensitive parallel rt-transition (term)"
  26    'PRedITNormal h G L T = (cnu h G L T).
  27
  28 (* Basic properties *********************************************************)
  29
  30 lemma cnu_sort (h) (G) (L): ∀s. ⦃G,L⦄ ⊢ ⥲[h] 𝐍⦃⋆s⦄.
  31 #h #G #L #s1 #n #X #H
  32 elim (cpm_inv_sort1 … H) -H #H #_ destruct //
  33 qed.
  34
  35 lemma cnu_ctop (h) (G): ∀i. ⦃G,⋆⦄ ⊢ ⥲[h] 𝐍⦃#i⦄.
  36 #h #G * [| #i ] #n #X #H
  37 [ elim (cpm_inv_zero1 … H) -H *
  38   [ #H #_ destruct //
  39   | #Y #X1 #X2 #_ #_ #H destruct
  40   | #m #Y #X1 #X2 #_ #_ #H destruct
  41   ]
  42 | elim (cpm_inv_lref1 … H) -H *
  43   [ #H #_ destruct //
  44   | #Z #Y #X0 #_ #_ #H destruct
  45   ]
  46 ]
  47 qed.
  48
  49 lemma cnu_zero (h) (G) (L): ∀I. ⦃G,L.ⓤ{I}⦄ ⊢ ⥲[h] 𝐍⦃#0⦄.
  50 #h #G #L #I #n #X #H
  51 elim (cpm_inv_zero1 … H) -H *
  52 [ #H #_ destruct //
  53 | #Y #X1 #X2 #_ #_ #H destruct
  54 | #m #Y #X1 #X2 #_ #_ #H destruct
  55 ]
  56 qed.
  57
  58 lemma cnu_gref (h) (G) (L): ∀l. ⦃G,L⦄ ⊢ ⥲[h] 𝐍⦃§l⦄.
  59 #h #G #L #l1 #n #X #H
  60 elim (cpm_inv_gref1 … H) -H #H #_ destruct //
  61 qed.