Call / cc implementation of map and filter functions

module CallCC =

    let rec private mapk k mapper = function
    | [] -> k []
    | h :: t -> t |> mapk (fun x -> k((mapper h) :: x)) mapper

    let map = mapk id

    let rec private filterk k predicate = function
    | [] -> k []
    | h :: t -> t |> filterk (fun x -> k (if (predicate h) then h :: x else x)) predicate

    let filter = filterk id

[1..10000]
|> CallCC.map (fun x -> x * x)
|> CallCC.filter (fun x -> (x % 2) = 0)