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

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  14
  15 include "lambda/terms/term.ma".
  16
  17 include "lambda/notation/functions/annotatedabstraction_2.ma".
  18
  19 (* ITERATED ABSTRACTION *****************************************************)
  20
  21 let rec abst d M on d ≝ match d with
  22 [ O   ⇒ M
  23 | S e ⇒ 𝛌. (abst e M)
  24 ].
  25
  26 interpretation "iterated abstraction (term)"
  27    'AnnotatedAbstraction d M = (abst d M).
  28
  29 lemma abst_plus: ∀A,m,n. 𝛌m+n.A = 𝛌m.𝛌n.A.
  30 #A #m elim m -m normalize //
  31 qed.