Boost C++ Libraries

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Class template optional_manipulator

boost::log::optional_manipulator

Synopsis

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

template<typename OptionalT, typename NoneT> 
class optional_manipulator {
public:

  // public member functions
  optional_manipulator(stored_optional_type, stored_none_type) noexcept;
  template<typename StreamT> void output(StreamT &) const;
};

Description

Stream manipulator for inserting an optional value.

`optional_manipulator` public member functions

optional_manipulator(stored_optional_type opt, stored_none_type none) noexcept;

Initializing constructor.

```
template<typename StreamT> void output(StreamT & stream) const;
```
The method outputs the value, if it is present, otherwise outputs the "none" marker.

Specializations

Class template optional_manipulator<OptionalT, void>