matita/matita/contribs/lambdadelta/basic_2/etc/fid/fid.etc

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  14
  15 include "basic_2/notation/relations/isidentity_2.ma".
  16 include "basic_2/static/frees.ma".
  17
  18 (* FREE VARIABLES IDENTITY FOR RESTRICTED CLOSURES **************************)
  19
  20 definition fid: relation2 … ≝ λL,T.
  21                 ∀f. L ⊢ 𝐅*⦃T⦄ ≡ f →  𝐈⦃f⦄.
  22
  23 interpretation "free variables identity (restricted closure)"
  24    'IsIdentity L T = (fid L T).
  25
  26 (* Basic properties *********************************************************)
  27
  28 lemma fid_sort: ∀L,s. 𝐈⦃L, ⋆s⦄.
  29 /2 width=3 by frees_inv_sort/ qed.
  30
  31 lemma fid_gref: ∀L,l. 𝐈⦃L, §l⦄.
  32 /2 width=3 by frees_inv_gref/ qed.