matita/matita/contribs/lambdadelta/basic_2/rt_computation/cpxs_cnx.ma

   1 (**************************************************************************)
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   3 (*      ||M||                                                             *)
   4 (*      ||A||       A project by Andrea Asperti                           *)
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  10 (*       \ /        This file is distributed under the terms of the       *)
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  13 (**************************************************************************)
  14
  15 include "basic_2/rt_transition/cnx_cnx.ma".
  16 include "basic_2/rt_computation/cpxs.ma".
  17
  18 (* UNBOUND CONTEXT-SENSITIVE PARALLEL RT-COMPUTATION FOR TERMS **************)
  19
  20 (* Properties with normal forms *********************************************)
  21
  22 lemma cpxs_cnx (h) (G) (L) (T1):
  23       (∀T2. ❪G,L❫ ⊢ T1 ⬈*[h] T2 → T1 ≛ T2) → ❪G,L❫ ⊢ ⬈𝐍[h] T1.
  24 /3 width=1 by cpx_cpxs/ qed.
  25
  26 (* Inversion lemmas with normal terms ***************************************)
  27
  28 lemma cpxs_inv_cnx1 (h) (G) (L):
  29       ∀T1,T2. ❪G,L❫ ⊢ T1 ⬈*[h] T2 → ❪G,L❫ ⊢ ⬈𝐍[h] T1 → T1 ≛ T2.
  30 #h #G #L #T1 #T2 #H @(cpxs_ind_dx … H) -T1
  31 /5 width=9 by cnx_teqx_trans, teqx_trans/
  32 qed-.