Question

Specifically I was thinking about equivalent functionality to 6.3 here:

http://www.siafoo.net/article/52

Answer 1

Scala is a static language and thus all code should exists at compile time. However, you can simulate the python feature using the Pimp-My-Library approach to add methods to existing class, without modifying the class itself. However, you cannot change an existing method. Example:

class Foo( val i: Int )

class RichFoo( f: Foo ) {
  def prettyPrint = "Foo(" + i + ")"
}

implicit def enrichFoo( f: Foo ) = new RichFoo(f)

val foo = new Foo( 667 )

println( foo.prettyPrint ) // Outputs "Foo(667)"