Scala self-typed trait and calling method on supertype -

lets have class this

class job(args:string) {    def config:map[string,string] = ...  } 

i want create trait can mixed in class add more configuration options. did this

trait extraconfig { self:job =>    override def config = self.config ++ map("extra","config") } 

unfortunately doesnt compile self.config becomes self recursive.

i tried doing

trait  extraconfig  extends job {} 

but job taking constructor param , dont know how thread through.

what best way solve this?

you looking abstract override modifier, use need explicitly extend job class, in trait can use members of superclass:

class job(args:string) {   def config:map[string,string] = map.empty }  trait extraconfig extends job {   abstract override def config =     super.config ++ map("extra" -> "config") }  val job = new job("name") extraconfig