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Struct front

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


// 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 data members
  result< front(Sequence &)>::type operator();


front public public data members

  1. result< front(Sequence &)>::type operator();