How to poll an std::future to see if it's result is available?

In the code snippet below I'm attempting to manually associate a promise set on one thread with a future checked on another. I then attempt to poll the future to see if it is ready but the loop never terminates. The call to future::wait_for() always returns future_status::deferred. If I remove the wait_for and instead loop for some fixed number of iterations with a sleep_for in the while loop I can get() the future as expected and the function exits normally.

Am I misunderstanding the correct usage of wait_for()? Is there any other way to poll for a future becoming available without blocking on a get() call?

#include <chrono>
#include <thread>
#include <future>
#include <iostream>

using namespace std;
using namespace std::chrono;
void DoSomeWork(int numIters, promise<int>& ret)
{
    int it = 0;
    for ( ; it < numIters; ++it)
    {
        cout << "Thread " << this_thread::get_id() << " working..." << endl;
        this_thread::sleep_for(milliseconds(1000));
    }
    ret.set_value(it);
}

void TestPromise()
{
    int its = 10;
    promise<int> aPromise;
    thread aThread(DoSomeWork, its, ref(aPromise));
    auto aFuture = aPromise.get_future();
    while (aFuture.wait_for(milliseconds(100)) != future_status::ready)
    {
        cout << "Thread " << this_thread::get_id() << " waiting..." << endl;
    }
    cout << "Work iterations: " << aFuture.get();
    aThread.join();
}
int main()
{
    TestPromise();
    return 0;
}