map over list with options

gistfile1.fs

let optionize f = 
    function
    | None -> None
    | Some(x) -> Some(f x)

let newListMap f list = List.map (optionize f) list

let listWithNull = [Some 0; Some 6; Some 3; None; Some 34; None; Some 1]

let square x = x*x

let list1 = List.map (optionize square) listWithNull


let list2 = newListMap square listWithNull