Scala class extends {}

Question

By chance I came across weird compiling Scala syntax:

class Some extends {
  def hi = println(\"hi\")
}
         


        

Answer 1

This is actually just a syntactical accident (I think). Scala allows early definitions which look like

class Some extends {
  ...
} with ATrait

so the parser also accepts class Some extends { ... } which is equivalent to class Some { ... } (source).