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diff tests/option.lac @ 198:ab86aa858e6c

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'Option' datatype encoding
author Adam Chlipala <adamc@hcoop.net>
date Sat, 09 Aug 2008 19:23:31 -0400
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/option.lac	Sat Aug 09 19:23:31 2008 -0400
@@ -0,0 +1,25 @@
+datatype option a = None | Some of a
+
+val none_Hi : option string = None
+val some_Hi = Some "Hi"
+val none_some_Hi : option (option string) = None
+val some_some_Hi = Some some_Hi
+
+val show = fn x => case x of None => "None" | Some x => x
+
+val show2 = fn x => case x of None => "None'" | Some x => show x
+
+val page = fn x => <html><body>
+        {cdata (show x)}
+</body></html>
+
+val page2 = fn x => <html><body>
+        {cdata (show2 x)}
+</body></html>
+
+val main : unit -> page = fn () => <html><body>
+        <li><a link={page none_Hi}>None1</a></li>
+        <li><a link={page some_Hi}>Some1</a></li>
+        <li><a link={page2 none_some_Hi}>None2</a></li>
+        <li><a link={page2 some_some_Hi}>Some2</a></li>
+</body></html>