binary_negate

Library:  General utilities

binary_negate  binary_function

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Members

binary_negate()

operator()()

A function object that returns the complement of the result of its binary predicate

#include <functional>

namespace std {
  template<class Predicate>
  class binary_negate;
}

binary_negate is the function object class that is the return type for the function adaptor not2(). not2(), known as a negator, takes a binary predicate function object as its argument and returns a binary predicate function object that is the complement of the original.

Note that not2() works only with function objects that are defined as subclasses of the class binary_function.

namespace std {
 
  template<class Predicate>
  class binary_negate : public 
       binary_function<typename Predicate::first_argument_type,
                       typename Predicate::second_argument_type,
                       bool>
  {
  public:

    typedef typename binary_function<
              typename Predicate::first_argument_type,
              typename Predicate::second_argument_type,
              bool>::second_argument_type second_argument_type;

    explicit binary_negate (const Predicate&);
    bool operator()
         (const typename Predicate::first_argument_type&,
          const typename Predicate::second_argument_type&)
         const;
  };

  // Nonmember Functions

  template <class Predicate>
  binary_negate<Predicate> not2 (const Predicate& pred);
}

explicit binary_negate(const Predicate& pred);

Constructs a binary_negate object from predicate pred.

bool 
operator()(const first_argument_type& x,
            const second_argument_type& y) const;

Returns the result of !pred(x,y).

binary_function, not2(), unary_negate

ISO/IEC 14882:1998 -- International Standard for Information Systems -- Programming Language C++, Section 20.3.5