...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::log::attribute::impl — A base class for an attribute value factory.
// In header: <boost/log/attributes/attribute.hpp> // A base class for an attribute value factory. struct impl : public boost::intrusive_ref_counter< impl > { // construct/copy/destruct ~impl(); // public member functions virtual attribute_value get_value() = 0; // public static functions static void * operator new(std::size_t); static void operator delete(void *, std::size_t) noexcept; };
All attributes must derive their implementation from this class.
impl
public member functionsvirtual attribute_value get_value() = 0;
Returns: |
The actual attribute value. It shall not return empty values (exceptions shall be used to indicate errors). |