matita/matita/contribs/lambdadelta/ground/relocation/rtmap.ma

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  14
  15 include "ground/relocation/nstream.ma".
  16
  17 (* RELOCATION MAP ***********************************************************)
  18
  19 lemma pn_split: ∀f. (∃g. ⫯g = f) ∨ (∃g. ↑g = f).
  20 @case_prop /3 width=2 by or_introl, or_intror, ex_intro/
  21 qed-.