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

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  14
  15 include "lambda/levels/term.ma".
  16
  17 include "lambda/notation/functions/annotatedabstraction_2.ma".
  18
  19 (* ITERATED ABSTRACTION *****************************************************)
  20
  21 definition labst: nat → lterm → lterm ≝ λh,M. match M with
  22 [ LVRef i e   ⇒ {i+h}§e
  23 | LAppl i C A ⇒ {i+h}@C.A
  24 ].
  25
  26 interpretation "iterated abstraction (term by level)"
  27    'AnnotatedAbstraction h M = (labst h M).
  28
  29 interpretation "abstraction (term by level)"
  30    'Abstraction M = (labst (S O) M).
  31
  32 lemma labst_O: ∀M. 𝛌0.M = M.
  33 * normalize //
  34 qed.