How to bind sequence query parameter?

Set the parameter to Seq[T]:

case class MyQP(seq: Seq[Int]) derives QueryStringRW

Let's consider a few possible requests with these query params:

• ? (empty) -> seq will be empty Seq()
• ?seq=123 -> seq will be Seq(123)
• ?seq[]=123&seq[]=456 -> seq will be Seq(123, 456)
• ?seq[1]=123&seq[0]=456 -> seq will be Seq(456, 123) (note it is sorted here)