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
Obtain a pointer to the target executor object.
template<
typename Executor>
const Executor * target() const;
If target_type() == typeid(T), a pointer to the stored executor
target; otherwise, a null pointer.