helm/software/matita/nlibrary/nat/nat.ma

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