matita/matita/contribs/lambdadelta/static_2/syntax/teqo_simple.ma

   1 (**************************************************************************)
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   3 (*      ||M||                                                             *)
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  10 (*       \ /        This file is distributed under the terms of the       *)
  11 (*        v         GNU General Public License Version 2                  *)
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  14
  15 include "static_2/syntax/term_simple.ma".
  16 include "static_2/syntax/teqo.ma".
  17
  18 (* SORT-IRRELEVANT OUTER EQUIVALENCE FOR TERMS ******************************)
  19
  20 (* Properies with simple (neutral) terms ************************************)
  21
  22 (* Basic_2A1: was: simple_tsts_repl_dx *)
  23 lemma simple_teqo_repl_dx: ∀T1,T2. T1 ~ T2 → 𝐒❨T1❩ → 𝐒❨T2❩.
  24 #T1 #T2 * -T1 -T2 //
  25 #I #V1 #V2 #T1 #T2 #H
  26 elim (simple_inv_pair … H) -H #J #H destruct //
  27 qed-.
  28
  29 (* Basic_2A1: was: simple_tsts_repl_sn *)
  30 lemma simple_teqo_repl_sn: ∀T1,T2. T1 ~ T2 → 𝐒❨T2❩ → 𝐒❨T1❩.
  31 /3 width=3 by simple_teqo_repl_dx, teqo_sym/ qed-.