matita/matita/lib/lambda/levels/iterated_abstraction.ma

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  14
  15 include "lambda/levels/term.ma".
  16
  17 (* ITERATED ABSTRACTION *****************************************************)
  18
  19 definition labst: nat → lterm → lterm ≝ λh,M. match M with
  20 [ LVRef i e   ⇒ {i+h}§e
  21 | LAppl i C A ⇒ {i+h}@C.A
  22 ].
  23
  24 interpretation "iterated abstraction (term by level)"
  25    'AnnotatedAbstraction h M = (labst h M).
  26
  27 interpretation "abstraction (term by level)"
  28    'Abstraction M = (labst (S O) M).
  29
  30 lemma labst_O: ∀M. 𝛌0.M = M.
  31 * normalize //
  32 qed.