helm/matita/tests/unfold.ma

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  14
  15 set "baseuri" "cic:/matita/unfold".
  16
  17 alias symbol "plus" (instance 0) = "Coq's natural plus".
  18 definition myplus \def \lambda x,y. x+y.
  19
  20 lemma lem: \forall n. S (n + n) = (S n) + n.
  21  intro; reflexivity.
  22 qed.
  23
  24 theorem trivial: \forall n. S (myplus n n) = (S n) + n.
  25  unfold myplus.
  26  intro.
  27  rewrite > lem.
  28  reflexivity.
  29 qed.