Abstract overrides

greeting.scala

trait Greeting {
  def greeting: String
}

trait Greeter {
  this: Greeting =>

  def greet() = greeting
}

trait GreetingDecorator extends Greeting {
  abstract override lazy val greeting = super.greeting + ", you insensitive clod"
}

trait DefEnglishGreeting extends Greeting {
  def greeting = "Hello"
}

trait ValEnglishGreeting extends Greeting {
  val greeting = "Hello"
}

trait LazyValEnglishGreeting extends Greeting {
  lazy val greeting = "Hello"
}

// trait SubclassedEnglishGreeting extends LazyValEnglishGreeting {
//   override def greeting = super.greeting + ", you insensitive clod"
// }

// Error:(28, 34) super may not be used on lazy value greeting
// override def greeting = super.greeting + ", you insensitive clod"
// ^

object DefEnglishGreeter extends Greeter with DefEnglishGreeting with GreetingDecorator

// object ValEnglishGreeter extends Greeter with ValEnglishGreeting with GreetingDecorator

// overriding value greeting in trait ValEnglishGreeting of type String;
// lazy value greeting in trait GreetingDecorator of type String cannot override a concrete non-lazy value
// object ValEnglishGreeter extends Greeter with ValEnglishGreeting with GreetingDecorator
// ^

object LazyValEnglishGreeter extends Greeter with LazyValEnglishGreeting with GreetingDecorator

DefEnglishGreeter.greet()

LazyValEnglishGreeter.greet()
// java.lang.StackOverflowError
//   at com.foo.common.config.archaius.A$A90$A$A90$LazyValEnglishGreeter$.com$foo$common$config$archaius$A$A90$A$A90$GreetingDecorator$$super$greeting(wks.sc0.tmp:35)
//   at com.foo.common.config.archaius.A$A90$A$A90$GreetingDecorator$class.greeting(wks.sc0.tmp:12)
//   at com.foo.common.config.archaius.A$A90$A$A90$LazyValEnglishGreeter$.greeting$lzycompute(wks.sc0.tmp:35)
//   at com.foo.common.config.archaius.A$A90$A$A90$LazyValEnglishGreeter$.greeting(wks.sc0.tmp:35)
//   at com.foo.common.config.archaius.A$A90$A$A90$LazyValEnglishGreeter$.com$foo$common$config$archaius$A$A90$A$A90$GreetingDecorator$$super$greeting(wks.sc0.tmp:35)