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Class template optional_manipulator<OptionalT, void>

boost::log::optional_manipulator<OptionalT, void>


// In header: <boost/log/utility/manipulators/optional.hpp>

template<typename OptionalT> 
class optional_manipulator<OptionalT, void> {
  // construct/copy/destruct
  optional_manipulator(stored_optional_type) noexcept;

  // public member functions
  template<typename StreamT> void output(StreamT &) const;


Stream manipulator for inserting an optional value. Specialization for no "none" marker.

optional_manipulator public construct/copy/destruct

  1. optional_manipulator(stored_optional_type opt) noexcept;
    Initializing constructor.

optional_manipulator public member functions

  1. template<typename StreamT> void output(StreamT & stream) const;
    The method outputs the value, if it is present.