matita/matita/contribs/lambdadelta/basic_2/etc/xpr/xpr.etc

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  14
  15 notation "hvbox( ⦃ term 46 h , break term 46 L ⦄ ⊢ break term 46 T1 • ➡ break [ term 46 g ] break term 46 T2 )"
  16    non associative with precedence 45
  17    for @{ 'XPRed $h $g $L $T1 $T2 }.
  18
  19 include "basic_2/static/ssta.ma".
  20 include "basic_2/reducibility/cpr.ma".
  21
  22 (* EXTENDED PARALLEL REDUCTION ON TERMS *************************************)
  23
  24 inductive xpr (h) (g) (L) (T1) (T2): Prop ≝
  25 | xpr_cpr : L ⊢ T1 ➡ T2 → xpr h g L T1 T2
  26 | xpr_ssta: ∀l. ⦃h, L⦄ ⊢ T1 •[g, l + 1] T2 → xpr h g L T1 T2
  27 .
  28
  29 interpretation
  30    "extended parallel reduction (term)"
  31    'XPRed h g L T1 T2 = (xpr h g L T1 T2).
  32
  33 (* Basic properties *********************************************************)
  34
  35 lemma xpr_refl: ∀h,g,L. reflexive … (xpr h g L).
  36 /2 width=1/ qed.