Mercurial > urweb
view tests/query.ur @ 1578:7d2aa0ddc531
Some notes on 'T' for update/delete combinators
author | Adam Chlipala <adam@chlipala.net> |
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date | Thu, 20 Oct 2011 09:27:37 -0400 |
parents | 5f9b9972e6b8 |
children |
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table t1 : {A : int, B : string, C : float, D : bool} table t2 : {A : float, D : int} datatype list a = Nil | Cons of a * list a val q1 = (SELECT * FROM t1) val r1 : transaction (list {A : int, B : string, C : float, D : bool}) = query q1 (fn fs acc => return (Cons (fs.T1, acc))) Nil val r2 : transaction string = ls <- r1; return (case ls of Nil => "Problem" | Cons ({B = b, ...}, _) => b) fun main () : transaction page = s <- r2; return <xml><body> {cdata s} </body></xml>