## Class missing_value

boost::log::missing_value — Exception class that is used to indicate errors of missing values.

## Synopsis

    // In header: <boost/log/exceptions.hpp>

    class missing_value : public runtime_error {
    public:
      // construct/copy/destruct
      missing_value();
      explicit missing_value(std::string const &);
      ~missing_value();
    };

## Description

### `missing_value` public construct/copy/destruct

1.     missing_value();

   Default constructor. Creates an exception with the default error message.

2.     explicit missing_value(std::string const & descr);

   Initializing constructor. Creates an exception with the specified error message.

3.     ~missing_value();

   Destructor