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comparison tests/datatypeP.ur @ 244:71bafe66dbe1

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Laconic -> Ur
author Adam Chlipala <adamc@hcoop.net>
date Sun, 31 Aug 2008 08:32:18 -0400
parents tests/datatypeP.lac@8a70e2919e86
children
comparison
equal deleted inserted replaced
243:2b9dfaffb008 244:71bafe66dbe1
1 datatype option a = None | Some of a
2
3 val none : option int = None
4 val some_1 : option int = Some 1
5
6 val f = fn t ::: Type => fn x : option t =>
7 case x of None => None | Some x => Some (Some x)
8
9 val none_again = f none
10 val some_1_again = f some_1
11
12 val show = fn t ::: Type => fn x : option t => case x of None => "None" | Some _ => "Some"
13
14 val page = fn x => <html><body>
15 {cdata (show x)}
16 </body></html>
17
18 val main : unit -> page = fn () => <html><body>
19 <li><a link={page none_again}>None</a></li>
20 <li><a link={page some_1_again}>Some 1</a></li>
21 </body></html>