matita/matita/contribs/lambda_delta/basic_2/etc/csup/yprs_xprs.etc

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  14
  15 include "basic_2/computation/xprs_cprs.ma".
  16 include "basic_2/computation/yprs.ma".
  17
  18 (* HYPER PARALLEL COMPUTATION ON CLOSURES ***********************************)
  19
  20 (* Properties on extended parallel computation for terms ********************)
  21
  22 lemma xprs_yprs: ∀h,g,L,T1,T2. ⦃h, L⦄ ⊢ T1 •➡*[g] T2 →
  23                  h ⊢ ⦃L, T1⦄ •⥸*[g] ⦃L, T2⦄.
  24 #h #g #L #T1 #T2 #H @(xprs_ind … H) -T2 // /3 width=4/
  25 qed.
  26
  27 lemma cprs_yprs: ∀h,g,L,T1,T2. L ⊢ T1 ➡* T2 → h ⊢ ⦃L, T1⦄ •⥸*[g] ⦃L, T2⦄.
  28 /3 width=1/ qed.