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comparison tests/datatypeP2.lac @ 194:df5fd8f6913a

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A multi-parameter datatype all the way through
author Adam Chlipala <adamc@hcoop.net>
date Sat, 09 Aug 2008 08:47:36 -0400
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193:8a70e2919e86 194:df5fd8f6913a
1 datatype sum a b = Left of a | Right of b
2
3 val l : sum int string = Left 5
4 val r : sum int string = Right "Hi"
5
6 val show = fn x : sum int string => case x of Left _ => "Left _" | Right s => s
7
8 val page = fn x => <html><body>
9 {cdata (show x)}
10 </body></html>
11
12 val main : unit -> page = fn () => <html><body>
13 <li><a link={page l}>Left</a></li>
14 <li><a link={page r}>Right</a></li>
15 </body></html>