matita/matita/lib/lambda/terms/iterated_abstraction.ma

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   3 (*      ||M||                                                             *)
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  14
  15 include "lambda/terms/term.ma".
  16
  17 (* ITERATED ABSTRACTION *****************************************************)
  18
  19 let rec abst d M on d ≝ match d with
  20 [ O   ⇒ M
  21 | S e ⇒ 𝛌. (abst e M)
  22 ].
  23
  24 interpretation "iterated abstraction (term)"
  25    'AnnotatedAbstraction d M = (abst d M).
  26
  27 lemma abst_plus: ∀A,m,n. 𝛌m+n.A = 𝛌m.𝛌n.A.
  28 #A #m elim m -m normalize //
  29 qed.