Need to explain in the readme what it does, and what for. Why would I need such an abstraction? What is the cost? Why is that any better than calling the func

Need to explain in the readme what it does, and what for. Why would I need such an abstraction? What is the cost? Why is that any better than calling the function with a single argument in the first place? I assume here it is maintaining a vector of futures and and a sibling vector of input values. And when this vector reaches the window size or something like that, it calls the original function with must returns a vector of results, which are then used to resolve the futures.