matita/matita/nlibrary/nat/nat.ma

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  14
  15 include "hints_declaration.ma".
  16 include "logic/equality.ma".
  17 include "sets/setoids.ma".
  18
  19 ninductive nat: Type[0] ≝
  20    O: nat
  21  | S: nat → nat.
  22
  23 ndefinition NAT: setoid.
  24  napply mk_setoid [ napply nat | napply EQ]
  25 nqed.
  26
  27 alias symbol "hint_decl" = "hint_decl_Type1".
  28 unification hint 0 ≔ ⊢ carr NAT ≡ nat.