// (C) Porkolab 2003 // // A.6.21. // Negater template <class Pred> class unary_negate : public unary_function<typename Pred::argument_type,bool> { Pred op; public: explicit unary_negate(const Pred& p) : op(p) { } bool operator()(const argument_type& x) const { return !op(x); } }; template <class Pred> class binary_negate : public binary_function<typename Pred::first_argument_type, typename Pred::second_argument_type, bool> { typedef first_argument_type Arg; typedef second_argument_type Arg2; Pred op; public: explicit binary_negate(const Pred& p) : op(p) { } bool operator()(const Arg& x, const Arg2& y) const { return !op(x,y); } }; template<class Pred> unary_negate<Pred> not1(const Pred& p); // negate unary template<class Pred> binary_negate<Pred> not2(const Pred& p); // negate binary