FParsec.FF.NewCustomer.fs

let (|NotMatch|_|) pattern s = 
    if Regex.IsMatch (s, pattern) then None
    else Some NotMatch

type Cap2 = private Cap2 of string
let cap2 = function
    | NotMatch "^[A-Z]{2}$" -> None
    | s -> Some <| Cap2 s

type StringAZ = private StringAZ of string
let stringAZ = function
    | NotMatch "^[A-Za-z ]+$" -> None
    | s -> Some <| StringAZ s

type StringAZ123 = private StringAZ123 of string
let stringAZ123 = function
    | NotMatch "^[A-Za-z0-9 ]+$" -> None
    | s -> Some <| StringAZ123 s

type PostInt5 = private PostalCode of int
let posint5 = function
    | i when string i |> String.length <> 5 || i <= 0 -> None
    | i -> Some <| PostalCode i

type Customer =
    { Country : Cap2
      FullName : StringAZ
      Street : StringAZ123
      City : StringAZ
      State : Cap2
      PostalCode : PostInt5 }