Question

I am a NOOB trying to understand some code.

What does this self.class.current_section do?

class MyClass
  class << self  
    def current_section(*section)
      if section.empty?
        @current_section
      else
        @current_section = section[0]
      end
    end
  end


  def current_section()
    self.class.current_section
  end

  def current_section=(section)
    self.class.current_section(section)
  end
end

Answer 1

It forwards the message (method call request) received by the object to the corresponding class.

Say you have a class

class MyClass
  def MyClass.current_section
    puts "I'm the class method."
  end

  def current_section
    self.class.current_section
  end
end

h = MyClass.new
h.current_section # outputs "I'm the class method."

Calling h‘s method, it looks up h‘s class (MyClass) and invokes the method current_section of that class.

So, by the definitions above, every object of the class MyClass has a method current_section which is routed to the central current_section of the class.

The definition of the class methods in your question is just using a different syntax for doing the same: adding a method to the class object.