matita/matita/contribs/lambda-delta/Basic-2/reduction/cpr_cpr.ma

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  14
  15 include "Basic-2/reduction/tpr_tpr.ma".
  16 include "Basic-2/reduction/cpr.ma".
  17
  18 (* CONTEXT-SENSITIVE PARALLEL REDUCTION ON TERMS ****************************)
  19
  20 (* Main properties **********************************************************)
  21 (*
  22 (* Basic-1: was: pr2_confluence *)
  23 theorem cpr_conf: ∀L,U0,T1,T2. L ⊢ U0 ⇒ T1 → L ⊢ U0 ⇒ T2 →
  24                   ∃∃T. L ⊢ T1 ⇒ T & L ⊢ T2 ⇒ T.
  25 #L #U0 #T1 #T2 * #U1 #HU01 #HUT1 * #U2 #HU02 #HUT2
  26 elim (tpr_conf … HU01 HU02) -U0 #U #HU1 #HU2
  27 qed.
  28 *)