How can I match classes in a Scala “match” statement?

Question

How can I use a \"match\" statement to identify the value of a class variable? The following is invalid, and I can\'t find an acceptable variant -- other than if ... else i

Answer 1

I encountered the same problem and placing the class in a 'stable identifier' wasn't that practical. I found the next best thing was to have tidy 'else if' statements.

Using this method:

private def is[T <: AnyRef : Manifest](implicit cls: Class[_]) = 
    cls == manifest[T].runtimeClass

I can write:

  implicit val arg = cls   
  if (is[ClassA]) ...
  else if (is[ClassB]) ...
  ...
  else throw new IllegalArgumentException("Unknown class: " + cls)