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view tests/sql_option.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 4efab85405be
children
line wrap: on
line source
table t : { O : option int }

fun addNull () =
    dml (INSERT INTO t (O) VALUES (NULL));
    return <xml>Done</xml>

fun add3 () =
    dml (INSERT INTO t (O) VALUES ({Some 3}));
    return <xml>Done</xml>

fun addN r =
    dml (INSERT INTO t (O) VALUES ({Some (readError r.N)}));
    return <xml>Done</xml>

fun main () : transaction page =
    xml <- queryX (SELECT * FROM t)
                  (fn r => case r.T.O of
                               None => <xml>Nada<br/></xml>
                             | Some n => <xml>Num: {[n]}<br/></xml>);
    return <xml><body>
      {xml}

      <a link={addNull ()}>Add a null</a><br/>
      <a link={add3 ()}>Add a 3</a><br/>
      <form>
        Add <textbox{#N}/> <submit action={addN}/>
      </form>
    </body></xml>