Selftype and Inheritance

gistfile1.scala

abstract class MyComparable[D <: MyComparable[D]] {
  this: D =>
  
  def <=(other: D)
  def >=(other: D) = (other <= this) // would fail without selftype
  
  // ...
}

abstract class MyEnhancedComparable[D <: MyEnhancedComparable[D]] extends MyComparable[D] {
  // Omitting this line results in:
  // - illegal inheritance; self-type MyEnhancedComparable[D] does not conform to MyComparable[D]'s 
  //   selftype D
  this: D =>
  
  // ... 
}