Ruby: Accessing calling child class constants from parent class?

Question

In Ruby, how can I access the calling class's constants from a parent class?

Module Foo
  class Base
    def test()
      #how do I access calling class's constants here?
      #ex: CallingClass.SOME_CONST
    end
  end
end

class Bar < Foo::Base
  SOME_CONST = 'test'
end

Answer 1

This seems to work - it forces constant lookup to scope into the current instance's class

module Foo
  class Base
    def test
      self.class::SOME_CONST
    end
  end
end

class Bar < Foo::Base
  SOME_CONST = 'test'
end

Bar.new.test # => 'test'