Accessing Class Variables?

Question

class Foo
  @@default = "default"

  p instance_variables
  p class_variables

  class << self
    p instance_variables
    p class_variables

    # How do I access the @@default variable here?
  end
end

Answer 1

The same way you do it in any other place: @@default.

I'm not sure what p .. is supposed to do (Ruby isn't my native language), but this works

class Foo
  @@default = "default"

  class << self
    puts "#{@@default}"
  end
end

Answer 2

This question is kind of interesting because it essentially asks "is there any way for the metaclass to reference its "real" class?

And as far as I can tell, the answer is "no", because all of the "upward" ancestor pointers Ruby keeps also point to metaclasses, and so running class_variables() in one of them will tell you about its class instance variables. So, you have to reference objects by name or just establish a handle before entering the metaclass context...

class Foo
  @@default = "default"
  @@me = self

  p instance_variables
  p class_variables

  class << self
    p instance_variables
    p @@me.class_variables
  end
end