Question

Is there a standard way of logically combining predicates in F#?
For example, let’s say I have isCar x and isBlue x then I want something that gives me:

let isBlueCar x = isCar x && isBlue x

But using some sort of composition, rather than invocation, maybe like:

let isBlueCar x = isCar && isBlue

Preferably, that something would be able to accept a large/arbitrary number of predicates.

Answer 1

You could define a combinator.

let (<&>) f g = (fun x -> f x && g x)

then do

let isBlueCar = isCar <&> isBlue