Constant in class << self block

Question

In the following fragment, is it possible to refer to the FOO constant from outside the module, and if so, how?

module X
  class << self
    FOO = 2
  end
end

Answer 1

class <<X
  self
end::FOO

or

class Object
  def metaclass
    class <<self
      self
    end
  end
end

X.metaclass::FOO