Mercurial > urweb
view tests/caseFfi.lac @ 198:ab86aa858e6c
'Option' datatype encoding
author | Adam Chlipala <adamc@hcoop.net> |
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date | Sat, 09 Aug 2008 19:23:31 -0400 |
parents | 19ee24bffbc0 |
children |
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extern structure M : sig datatype t = A | B datatype u = C of t | D end val f = fn x => case x of M.A => M.B | M.B => M.A val t2s = fn x => case x of M.A => "A" | M.B => "B" val g = fn x => case x of M.C a => M.C (f a) | M.D => M.C M.A val u2s = fn x => case x of M.C a => t2s a | M.D => "D" val page = fn x => <html><body> {cdata (t2s x)} </body></html> val page2 = fn x => <html><body> {cdata (u2s x)} </body></html> val main : unit -> page = fn () => <html><body> <li><a link={page M.A}>A</a></li> <li><a link={page M.B}>B</a></li> <li><a link={page2 (M.C M.A)}>C A</a></li> <li><a link={page2 (M.C M.B)}>C B</a></li> <li><a link={page2 M.D}>D</a></li> </body></html>