Effects: For each service object svc in the execution_context set, in reverse order of addition to the set, performs svc->shutdown(). For each service in the set, svc->shutdown() is called only once irrespective of the number of calls to shutdown on the execution_context.
void destroy() noexcept;
Effects: Destroys each service object in the execution_context set, and removes it from the set, in reverse order of addition to the set.