matita/tests/fold.ma

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  14
  15 set "baseuri" "cic:/matita/tests/fold".
  16 include "legacy/coq.ma".
  17 alias id "nat" = "cic:/Coq/Init/Datatypes/nat.ind#xpointer(1/1)".
  18 alias num (instance 0) = "natural number".
  19 alias symbol "eq" (instance 0) = "Coq's leibnitz's equality".
  20 alias symbol "plus" (instance 0) = "Coq's natural plus".
  21 theorem t: \forall x:nat. 0+x=x.
  22  intro.
  23  simplify in match (0+x) in \vdash (? ? % ?).
  24  fold simplify (0 + x) in \vdash (? ? % ?).
  25  reflexivity.
  26 qed.