matita/matita/contribs/lambdadelta/ground_2/etc/lib/list2_append.etc

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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 "ground_2/notation/functions/oplus_4.ma".
  16 include "ground_2/lib/list2.ma".
  17
  18 (* LISTS OF PAIRS ***********************************************************)
  19
  20 rec definition append2 A1 A2 (l1,l2:list2 A1 A2) on l1 ≝ match l1 with
  21 [ nil2           ⇒ l2
  22 | cons2 a1 a2 tl ⇒ {a1, a2} ⨮ append2 A1 A2 tl l2
  23 ].
  24
  25 interpretation "append (list of pairs)"
  26    'OPlus A1 A2 l1 l2 = (append2 A1 A2 l1 l2).