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view tests/query.ur @ 1893:9a1097954188

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compileC: Link libraries in the right order This is needed, at least on recent Ubuntu, to fix this linker error when compiling any Ur/Web application: ld: /tmp/webapp.o: undefined reference to symbol 'uw_write' Signed-off-by: Anders Kaseorg <andersk@mit.edu> --- src/compiler.sml | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
author Anders Kaseorg <andersk@mit.edu>
date Thu, 21 Nov 2013 14:32:11 -0500
parents 5f9b9972e6b8
children
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line source
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>