create_task with asynchronous unwrapping PPL

[Daniel Ramnath]

I have a code as below.

// async-unwrapping.cpp
// compile with: /EHsc
#include
#include

using namespace concurrency;
using namespace std;

int wmain()
{
auto t = create_task([]()
{
wcout << L"Task A" << endl;

    // Create an inner task that runs before any continuation
    // of the outer task.
    return create\_task(\[\]()
    {
        wcout << L"Task B" << endl;
    });
});

// Run and wait for a continuation of the outer task.
t.then(\[\](task& t3) // or task t3
{
    wcout << L"Task C" << endl;
    t3.wait(); // or .get()
}).wait();

}

I expected the output to be /* Output: Task A Task B Task C Task B */ But the output is /* Output: Task A Task B Task C */ Why t3.wait(); isn't calling the B task again or a tleast should throw error?

Jesus saves

[Lost User]

That's the thing with parallelism, it never does what you expect.