32 Concurrency support library [thread]

32.3 Stop tokens [thread.stoptoken]

32.3.6 Class template stop_callback [stopcallback]

32.3.6.1 General [stopcallback.general]

namespace std { template<class CallbackFn> class stop_callback { public: using callback_type = CallbackFn; // [stopcallback.cons], constructors and destructor template<class Initializer> explicit stop_callback(const stop_token& st, Initializer&& init) noexcept(is_nothrow_constructible_v<CallbackFn, Initializer>); template<class Initializer> explicit stop_callback(stop_token&& st, Initializer&& init) noexcept(is_nothrow_constructible_v<CallbackFn, Initializer>); ~stop_callback(); stop_callback(const stop_callback&) = delete; stop_callback(stop_callback&&) = delete; stop_callback& operator=(const stop_callback&) = delete; stop_callback& operator=(stop_callback&&) = delete; private: CallbackFn callback-fn; // exposition only }; template<class CallbackFn> stop_callback(stop_token, CallbackFn) -> stop_callback<CallbackFn>; }

Mandates: stop_callback is instantiated with an argument for the template parameter CallbackFn that satisfies both invocable and destructible .

Remarks: For a type Initializer, if stoppable-callback-for<CallbackFn, stop_token, Initializer> is satisfied, then stoppable-callback-for<CallbackFn, stop_token, Initializer> is modeled.

The exposition-only callback-fn member is the associated callback function ([stoptoken.concepts]) of stop_callback<
CallbackFn> objects.