Generalized type constraints in ScalikeJDBC

build.sbt

libraryDependencies ++= Seq(
  "com.github.seratch" %% "scalikejdbc"  % "1.3.0",
  "org.slf4j"          %  "slf4j-simple" % "1.6.4",
  "com.h2database"     %  "h2"           % "[1.3,)"
)

initialCommands := """import scalikejdbc._
|Class.forName("org.h2.Driver")
|ConnectionPool.singleton("jdbc:h2:mem:tmp", "", "")
|implicit val session = DB.autoCommitSession
|SQL("create table user (id bigint, name varchar(256))").execute.apply()
|val insert = SQL("insert into user values (?, ?)")
|insert.bind(1, "Alice").update.apply()
|insert.bind(2, "Bob").update.apply()
""".stripMargin

//
// scala> SQL("select * from user").list.apply()
// <console>:12: error: Cannot prove that scalikejdbc.SQL[Nothing,scalikejdbc.NoExtractor] =:= scalikejdbc.SQL[Nothing,scalikejdbc.HasExtractor].
//               SQL("select * from user").list.apply()
//
// scala> SQL("select * from user").map(rs => rs.string("name")).list.apply()
// res2: List[java.lang.String] = List(Alice, Bob)
//