Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

The type of cancellation_slot associated with this object.

using cancellation_slot_type = beast::detail::filtering_cancellation_slot< net::associated_cancellation_slot_t< Handler > >;

If a class derived from async_base is a completion handler, then the associated cancellation_slot of the derived class will be this type.

The default type is a filtering cancellation slot, that only allows terminal cancellation.