matita/matita/contribs/lambdadelta/basic_2/reduction/cnx_cix.ma

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  14
  15 include "basic_2/reduction/cpx_cix.ma".
  16 include "basic_2/reduction/cnx_crx.ma".
  17
  18 (* CONTEXT-SENSITIVE EXTENDED NORMAL TERMS **********************************)
  19
  20 (* Main properties on context-sensitive extended irreducible terms **********)
  21
  22 theorem cix_cnr: ∀h,g,L,T. ⦃G, L⦄ ⊢ 𝐈[h, g]⦃T⦄ → ⦃G, L⦄ ⊢ 𝐍[h, g]⦃T⦄.
  23 /2 width=5 by cpx_fwd_cix/ qed.
  24
  25 (* Main inversion lemmas on context-sensitive extended irreducible terms ****)
  26
  27 theorem cnr_inv_cix: ∀h,g,L,T. ⦃G, L⦄ ⊢ 𝐍[h, g]⦃T⦄ → ⦃G, L⦄ ⊢ 𝐈[h, g]⦃T⦄.
  28 /2 width=6 by cnx_inv_crx/ qed-.