FizzBuzz.fsx

let (|ModZero|_|) d v =
    match v % d with
    | 0 -> Some ()
    | _ -> None

let fizzBuzz = function
    | ModZero 15 -> printfn "fizzbuzz"
    | ModZero 3 -> printfn "fizz" 
    | ModZero 5 -> printfn "buzz" 
    | i  -> printfn "%i" i

[0..30]
|> List.iter fizzBuzz

[for x in 0 .. 30 -> fizzBuzz]
|> List.iteri (fun i f -> f i)