17 Language support library [language.support]

17.12 Coroutines [support.coroutine]

17.12.4 No-op coroutines [coroutine.noop] Class coroutine_­handle<noop_­coroutine_­promise> [coroutine.handle.noop] Resumption [coroutine.handle.noop.resumption]

constexpr void operator()() const noexcept; constexpr void resume() const noexcept; constexpr void destroy() const noexcept;
Effects: None.
Remarks: If noop_­coroutine_­handle is converted to coroutine_­handle<>, calls to operator(), resume and destroy on that handle will also have no observable effects.