Mercurial > urweb

open List

functor Make(M : sig
                 type t
                 val toString : t -> string
                 val fromString : string -> option t
             end) = struct
    fun toXml (ls : list M.t) =
        case ls of
            Nil => <xml>[]</xml>
          | Cons (x, ls') => <xml>{[M.toString x]} :: {toXml ls'}</xml>

    fun console (ls : list M.t) = return <xml><body>
      Current list: {toXml ls}<br/>
      Reversed list: {toXml (rev ls)}<br/>
      Length: {[length ls]}<br/>
      <br/>

      <form>
        Add element: <textbox{#X}/> <submit action={cons ls}/>
      </form>
    </body></xml>

    and cons (ls : list M.t) (r : {X : string}) =
        case M.fromString r.X of
            None => return <xml><body>Invalid string!</body></xml>
          | Some v => console (Cons (v, ls))

    fun main () = console Nil
end
author	Adam Chlipala <adamc@hcoop.net>
date	Tue, 11 Nov 2008 18:39:38 -0500
parents	e756d3a47726
children	7ef4b2911b09