Boost C++ Libraries

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Struct first

boost::xpressive::op::first — first is a PolymorphicFunctionObject for fetching the first element of a pair.

Synopsis

// In header: <boost/xpressive/regex_actions.hpp>


struct first {
  // member classes/structs/unions
  template<typename Sig> 
  struct result {
  };
  template<typename This, typename Pair> 
  struct result<This(Pair)> {
    // types
    typedef remove_reference< Pair >::type::first_type type;
  };

  // public member functions
  template<typename Pair> Pair::first_type operator()(Pair const &) const;
};

Description

first public member functions

  1. template<typename Pair> Pair::first_type operator()(Pair const & p) const;

    Parameters:

    p

    The pair from which to fetch the first element.

    Returns:

    p.first


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