uni20::async::TaskAwaitable Concept Reference

Concept for awaitables that accept promise-neutral task ownership. More...

#include <async_task_promise.hpp>

Concept definition

template<typename T>
concept uni20::async::TaskAwaitable =  requires(T a, BasicTask task) {
  { a.await_suspend(std::move(task)) } noexcept -> AwaitSuspendResult;
}

Detailed Description

Concept for awaitables that accept promise-neutral task ownership.

This concept is satisfied if the awaitable provides:

• non-throwing await_suspend(BasicTask)
• The return type of await_suspend is void or BasicTask

Note

This concept disallows await_suspend() from returning a coroutine_handle, to ensure that ownership and resumption are managed solely by the scheduler.

Suspension must not throw after accepting coroutine ownership because ownership transfer cannot be rolled back in general.