Generalized async return types

If you use async/await (if not, check it out) the following feature of C# 7.0 will come in really handy. The only supported return types used to be Task<T>, Task, and void. Even then, void was also only used with event handlers such as a button click. The challenge, however, was that a Task<T> was allocated in situations where the result of the async operation was available at the time of awaiting. But, what does this even mean? Well consider an async method that returns a Task<T> : and that value has a time to live of n amount of seconds. If the async method is called within the time to live period, why go to the trouble of allocating another Task<T> object? This is where the ValueTask<T> comes into play; it will allow other types to be defined so that you can return them from an async method. This, therefore, reduces the Task<T> allocations, which in turn will lead to performance gains.