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view tests/datatypeP.ur @ 970:8371d12ae63f

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Hopefully complete refactoring of Jscomp to output ASTs; partial implementation of interpreter in runtime system (demo/alert works)
author Adam Chlipala <adamc@hcoop.net>
date Tue, 22 Sep 2009 12:23:21 -0400
parents 71bafe66dbe1
children
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datatype option a = None | Some of a

val none : option int = None
val some_1 : option int = Some 1

val f = fn t ::: Type => fn x : option t =>
        case x of None => None | Some x => Some (Some x)

val none_again = f none
val some_1_again = f some_1

val show = fn t ::: Type => fn x : option t => case x of None => "None" | Some _ => "Some"

val page = fn x => <html><body>
        {cdata (show x)}
</body></html>

val main : unit -> page = fn () => <html><body>
        <li><a link={page none_again}>None</a></li>
        <li><a link={page some_1_again}>Some 1</a></li>
</body></html>