Not cake

Cake.scala

trait FooComponent {

  def bar: BarComponent#Bar

  case class Foo(foofy: String)
}

trait BarComponent {
  def foo: FooComponent#Foo

  case class Bar(bah: String)
}

object System extends App with FooComponent with BarComponent {

  val foo = Foo("foo")
  val bar = Bar("bar")

  println(s"${foo.foofy} and ${bar.bah}")
}

So, what can cake do that this can't?

1. Clever type things (path dependent types?)
2. avoid name clashes between components
3. cake declares the component's instance in the component, so its local
4. The above declares dependencies through an abstract def, cake uses self types so the component itself declares its dependencies - not sure what that really means

What else?

http://stackoverflow.com/questions/7012013/why-use-scalas-cake-pattern-rather-than-abstract-fields