Add the namespace reference

C#
using CI.TaskParallel;

Unity gameobjects cannot be updated from background threads, if you need to modify one then it should be done using one of the RunOnUIThread methods

C#
var unityTask = new UnityTask(() =>
{
    // Do some work on a background thread
});
unityTask.Start();

// This can be simplified using the static Run method
var unityTask = UnityTask.Run(() =>
{
    // Do some work on a background thread
}); 

C#
var unityTask = new UnityTask<int>(() =>
{
    // Do some work on a background thread and then return a value
    return 0;
});
unityTask.Start();

// This can be simplified using the static Run method
var unityTask = UnityTask.Run(() =>
{
    // Do some work on a background thread and then return a value
    return 0;
});

Unity gameobjects cannot be interacted with from background threads, so we must run code that interacts with them on the UI thread. A continuation can be used which takes the result of the previous UnityTask (if there was one) and then runs the following action on the UI thread

C#
UnityTask.Run(() =>
{
    // Do some work on a background thread and then return a value which will be passed to the continuation
    return 0;
}).ContinueOnUIThread(t =>
{
    // Update a gameobject with the result of the previous UnityTask
    ResultText.text = "The result is: " + t.Result.ToString();
});

The static RunOnUIThread method can also be used

C#
UnityTask.RunOnUIThread(() =>
{
    // Update a gameobject
});

It's possible to chain multiple UnityTasks together with the result of the previous being passed to the next

C#
UnityTask.Run(() =>
{
    // Do some work on a background thread and then return a value
    return 0;
}).ContinueWith((t) =>
{
    // Do some more work on another background thread and then return a value
    return t.Result + 1;
});

Each UnityTask instance has a "wait" function which will block the calling thread until it completes

C#
var unityTask = UnityTask.Run(() =>
{
    // Do some work on a background thread and then return a value
    return 0;
});
unityTask.Wait();

There is also a static "WaitAll" to wait for multiple UnityTasks

C#
var t1 = UnityTask.Run(() =>
{
    // Do some work on a background thread
});
var t2 = UnityTask.Run(() =>
{
    // Do some work on a background thread
});
UnityTask.WaitAll(t1, t2);

If you don't want to block the calling thread then use "WhenAll" which raises a callback on the UI thread when all the supplied UnityTasks have completed

C#
var t1 = UnityTask.Run(() =>
{
    // Do some work on a background thread
});
var t2 = UnityTask.Run(() =>
{
    // Do some work on a background thread
});
UnityTask.WhenAll(() => 
{
    // Raised when all the supplied UnityTasks have completed
}, t1, t2);