Boost C++ Libraries

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Class type_dispatcher

boost::log::type_dispatcher — A type dispatcher interface.

Synopsis

// In header: <boost/log/utility/type_dispatch/type_dispatcher.hpp>


class type_dispatcher {
public:
  // member classes/structs/unions
  template<typename T> 
  class callback {
  public:

    // public member functions
    void operator()(T const &) const;
    explicit operator bool() const noexcept;
    bool operator!() const noexcept;
  };
  // construct/copy/destruct
  explicit type_dispatcher(get_callback_impl_type) noexcept;
  type_dispatcher(type_dispatcher const &) = default;
  type_dispatcher & operator=(type_dispatcher const &) = default;
  ~type_dispatcher();

  // public member functions
  template<typename T> callback< T > get_callback();
};

Description

All type dispatchers support this interface. It is used to acquire the visitor interface for the requested type.

`type_dispatcher` public construct/copy/destruct

explicit type_dispatcher(get_callback_impl_type get_callback_impl) noexcept;

Initializing constructor

type_dispatcher(type_dispatcher const & that) = default;

type_dispatcher & operator=(type_dispatcher const & that) = default;

```
~type_dispatcher();
```

`type_dispatcher` public member functions

```
template<typename T> callback< T > get_callback();
```
The method requests a callback for the value of type T

Returns:

The type-specific callback or an empty value, if the type is not supported