Boost C++ Libraries

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Struct front

boost::xpressive::op::front — front is a PolymorphicFunctionObject for fetching the front element of a container.

Synopsis

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


struct front {
  // member classes/structs/unions
  template<typename Sig> 
  struct result {
  };
  template<typename This, typename Sequence> 
  struct result<This(Sequence)> {
    // types
    typedef remove_reference< Sequence >::type                                                                                              sequence_type;
    typedef mpl::if_c< is_const< sequence_type >::value, typename sequence_type::const_reference, typename sequence_type::reference >::type type;         
  };

  // public member functions
  template<typename Sequence> 
    result< front(Sequence &)>::type operator()(Sequence &) const;
};

Description

front public member functions

  1. template<typename Sequence> 
      result< front(Sequence &)>::type operator()(Sequence & seq) const;

    Parameters:

    seq

    The sequence from which to fetch the front.

    Returns:

    seq.front()


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