var e = Eat(504, 1500);
e.Then(new (v) =>
	{
		if (v case .Ok(let val))
			Console.WriteLine(val);
	});

Console.WriteLine("Doing some calculations here");

var res = e.Await();
switch (res)
{
	case .Err:
	case .Ok(let val):
		Console.WriteLine(val + 2);
}
delete e;

Promises as a feature are not exactly consistent between programming languages.
This Beef implementation takes some inspiration from rust. When you create a promise the function thats passed in will be executed asynchronously by a threadpool.
Meanwhile the context that started to thread can continue executing until it calls Await, at which point it will block.

• Create(Promise<T, E> p, delegate Result<T, E>(PromiseValue v) func, PoolExecutor executor) Attaches the function to be executed asynchronously func onto the promise p and tells executor to execute it
• Promise.Resolved A non blocking call that returns wether the function is done
• Promise.Await() : Result<T, E> Blocks the current context until func is done, and returns a Result
• OnCleanup(delegate void(Result<T, E>) func) This method should be used to cleanup allocations in func that need to live beyond its scope
• Then(delegate void(Result<T, E>) func) Executes after the func is done
• OnErr(delegate void(E) func) Executes after the func is done. Only when it errored
• OnOk(delegate void(T) func)* Executes after the func is done. Only when its successfull