JDBC query using scala-arm

stringQuery.scala

def sql[T](q: String)(f: ResultSet => T): Either[List[Throwable], T] = (for {
  connection <- managed( datasource.getConnection )
  statement  <- managed( connection.createStatement )
  resultSet  <- managed( statement.executeQuery(q) )
} yield resultSet).acquireFor(f)

def sql[T](q: String)(f: ResultSet => T): Either[List[Throwable], T] = 
  (for {
     connection <- managed(datasource.getConnection)
     statement <- managed(connection.createStatement)
     resultSet <- managed(statement executeQuery q)
   } yield resultSet) aquireFor f

Without so many ()....

And with delimited continuations:

def sql[T](q: String)(f: ResultSet => T): Either[List[Throwable],T] =
  withResources {
    def r[R: Resource](t: =>R) = managed(t).reflect[T]
    val connection = r(datasource.getConnection)
    val statement = r(connection.createStatement)
    val resultSet = r(statement executeQuery q)
    f(resultSet)
  }

The r function is a bit odd, but helps reduce some boilerplate. The code compiles to the same as before, it just looks "flat" if you prefer. The downside to delimited continuations is the failure to infer the type to the reflect call. That's why you have a bit more work here, but it's not bad.