I am looking for the name and info on a pattern (?) that I'm contemplating. As I don't know the name, it's difficult to search for it.
Here's what I'm trying to do, with a totally hypothetical example...
find-flight ( trip-details, 'cheapest') :: flight
I have this public function, find-flight(...), that accepts 2 parameters, trip-details and some instruction to apply. It returns a single flight, not a list of them.
When I call it with 'cheapest', the function will wait for all available flight results to come in from expedia, travelocity, hotwire, etc, to assure the cheapest flight is found.
When I call it with 'shortest-flight', the function would do the same kind of underlying work as 'cheapest' but would return the shortest flight. I'm sure you can come up with other instructions to apply.
BUT! I'm specifically interested in a variant of this: the instruction (implied or not) would be 'I-am-filthy-rich-and-I-want-to-buy-a-ticket-now'. In other words, the function would call all the sources such as expedia, orbitz, etc, but would return the very first internally received result, at any price point.
I'm asking because I want my public function to be as quick as possible. I can think of a number of strategies that would make it respond fast, but I'm not sure that I know which approach would be best considering that the parameter is unknown until called, right?
So I'm thinking about writing various versions of this function that would all be called by the public version. It'd return the first result. Then, the other strategies could optionally be aborted. If I did that, I could get some metrics on the function and further optimize.
If I were to write this in Java, I'd have a bunch of future objects that the function would loop through to see which one is done first. I'd return that one.
What's that called?