view tests/ascdesc.ur @ 1886:b7cd3c7c7edd

Interpret 'table' signature items more flexibly, automatically adding (Ur) constraints to support a kind of subtyping over (SQL) constraint sets
author Adam Chlipala <adam@chlipala.net>
date Mon, 04 Nov 2013 15:14:23 -0500
parents 6f046b4bad24
children
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table t : { A : int }

fun sortEm b =
    queryX1 (SELECT * FROM t ORDER BY t.A {if b then sql_asc else sql_desc})
    (fn r => <xml>{[r.A]}; </xml>)

fun main () : transaction page = return <xml><body>
  <a link={sortEm True}>Ascending</a><br/>
  <a link={sortEm False}>Descending</a>
</body></xml>