An example of Kleisli composition

KleisliComposition.fsx

// An example of Kleisli composition

let (>>=) m f = Option.bind f m
let (>=>) mf mg = fun x -> mf x >>= mg

let tryParseInt s = 
    match System.Int32.TryParse s with
    | true, v -> Some v
    | _ -> None

let name = function
| 0 -> Some "zero"
| 1 -> Some "jeden"
| 2 -> Some "dwa"
| _ -> None

let nameHead = List.tryHead >=> tryParseInt >=> name

nameHead []
nameHead ["x";"123";"789"]
nameHead ["2";"123";"789"]
nameHead ["123";"456";"789"]