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annotate tests/datatypeP.lac @ 191:aa54250f58ac

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Parametrized datatypes through explify
author Adam Chlipala <adamc@hcoop.net>
date Fri, 08 Aug 2008 10:28:32 -0400
parents
children 8a70e2919e86
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adamc@191 1 datatype option a = None | Some of a
adamc@191 2
adamc@191 3 val none : option int = None
adamc@191 4 val some_1 : option int = Some 1
adamc@191 5
adamc@191 6 val f = fn t ::: Type => fn x : option t =>
adamc@191 7 case x of None => None | Some x => Some (Some x)
adamc@191 8
adamc@191 9 val none_again = f none
adamc@191 10 val some_1_again = f some_1