Referring to the type of an inner class in Scala

Question

The following code tries to mimic Polymorphic Embedding of DSLs: rather than giving the behavior in Inner, it is encoded in the useInner method of

Answer 1

The problem is as you describe, that useInner is expecting an Inner of a specific Outer instance. Since enclosing returns a generic Outer, there is really no way to tie both together that I know of.

You can force it, however:

def toBoolean(x: Outer#Inner): Boolean = {
  val outer = x.enclosing
  outer.useInner(x.asInstanceOf[outer.Inner])
}