Class template attribute_value_impl

boost::log::attributes::attribute_value_impl — Basic attribute value implementation class.

Synopsis

// In header: <boost/log/attributes/attribute_value_impl.hpp>

template<typename T> 
class attribute_value_impl : public attribute_value::impl {
public:
  // types
  typedef T value_type;  // Value type. 

  // public member functions
  explicit attribute_value_impl(value_type const &);
  explicit attribute_value_impl(value_type &&) noexcept(boost::is_nothrow_move_constructible< value_type >::value);
  virtual bool dispatch(type_dispatcher &);
  virtual typeindex::type_index get_type() const;
  value_type const & get() const;
};

Description

This class can be used as a boilerplate for simple attribute values. The class implements all needed interfaces of attribute values and allows to store a single value of the type specified as a template parameter. The stored value can be dispatched with type dispatching mechanism.

`attribute_value_impl` public member functions

explicit attribute_value_impl(value_type const & v);

Constructor with initialization of the stored value

explicit attribute_value_impl(value_type && v) noexcept(boost::is_nothrow_move_constructible< value_type >::value);

Constructor with initialization of the stored value

```
virtual bool dispatch(type_dispatcher & dispatcher);
```
Attribute value dispatching method.

Parameters:

dispatcher

The dispatcher that receives the stored value

Returns:

true if the value has been dispatched, false otherwise

virtual typeindex::type_index get_type() const;

Returns:

The attribute value type

```
value_type const & get() const;
```
Returns:

Reference to the contained value.

Boost C++ Libraries