Question

Is there (or will in the nearest feature) in scala possible to create case class with named parameters? I mean to construct case class object using named parameters in constructor.

My case classes have a lot of fields. It is prone to error having constructors with a lot of not named parameters.

I would like to get (at the moment not working example):

case class X(x0:String, x1:Int, x2:String)
val x = X(x0="Xstring", x1=12, x2="x2String")

As workaround we could provide factory method like below excerpt shows, but this is ugly solution:

case class X(x0:String, x1:Int, x2:String)
object X {
    private nullX = X(null, null, null)
    def createX = nullX.copy _
}

val x = X.createX(x0="Xstring", x1=12, x2="x2String")

Any clues ? 🙂

EDIT:
This was bug in intellij idea scala plugin some old version. Plase don’t vote down any more 😉

Answer 1

Named and default arguments were introduced in Scala 2.8

Welcome to Scala version 2.9.1.final (Java HotSpot(TM) 64-Bit Server VM, Java 1.6.0_27).
Type in expressions to have them evaluated.
Type :help for more information.

scala> case class X(x0:String, x1:Int, x2:String)
defined class X

scala> val x = X(x0="Xstring", x1=12, x2="x2String")
x: X = X(Xstring,12,x2String)