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Boost C++ Libraries

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Struct first

boost::proto::functional::first — A PolymorphicFunctionObject type that returns the first element of a std::pair<>.

Synopsis

// In header: <boost/proto/functional/std/utility.hpp>

struct first :  proto::callable {
  // member classes/structs/unions
  template<typename This, typename Pair> 
  struct result<This(Pair)> {
    // types
    typedef typename Pair::first_type type;
  };
  template<typename This, typename Pair> 
  struct result<This(Pair &)> {
    // types
    typedef typename Pair::first_type & type;
  };
  template<typename This, typename Pair> 
  struct result<This(Pair const &)> {
    // types
    typedef typename Pair::first_type const & type;
  };
  // public member functions
  template<typename Pair> typename Pair::first_type & operator()(Pair &) const;
  template<typename Pair> 
    typename Pair::first_type const & operator()(Pair const &) const;
};

Description

Тип PolymorphicFunctionObject, возвращающий первый элемент std::pair<>.

`first` public member functions

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Struct first

Boost , The Boost C++ Libraries BoostBook Documentation Subset , Reference

Boost C++ Libraries

Struct first

Synopsis

Description

first public member functions

`first` public member functions