adamc@198: datatype option a = None | Some of a
adamc@198:
adamc@198: val none_Hi : option string = None
adamc@198: val some_Hi = Some "Hi"
adamc@198: val none_some_Hi : option (option string) = None
adamc@198: val some_some_Hi = Some some_Hi
adamc@198:
adamc@198: val show = fn x => case x of None => "None" | Some x => x
adamc@198:
adamc@198: val show2 = fn x => case x of None => "None'" | Some x => show x
adamc@198:
adamc@198: val page = fn x =>
adamc@198: {cdata (show x)}
adamc@198:
adamc@198:
adamc@198: val page2 = fn x =>
adamc@198: {cdata (show2 x)}
adamc@198:
adamc@198:
adamc@198: val main : unit -> page = fn () =>
adamc@198: None1
adamc@198: Some1
adamc@198: None2
adamc@198: Some2
adamc@198: