Mercurial > urweb
view tests/limit.ur @ 1507:ca8c8b8cc477
Tutorial: TLC meets type classes and modules
author | Adam Chlipala <adam@chlipala.net> |
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date | Sun, 17 Jul 2011 13:04:07 -0400 |
parents | 02e1870a0516 |
children |
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table t : {A : int, B : string, C : float} val q1 = (SELECT * FROM t LIMIT 42) val q2 = fn n => (SELECT * FROM t LIMIT {n}) val q3 = (SELECT * FROM t OFFSET 3) val q4 = fn n => fn m => (SELECT * FROM t LIMIT {n} OFFSET {m}) datatype list a = Nil | Cons of a * list a val r1 : transaction (list {A : int, B : string, C : float}) = query (q4 3 7) (fn fs acc => return (Cons (fs.T, acc))) Nil val r2 : transaction string = ls <- r1; return (case ls of Nil => "Problem" | Cons ({B = b, ...}, _) => b) val main : unit -> transaction page = fn () => s <- r2; return <html><body> {cdata s} </body></html>