How can a nested class access a method in the outer class in Ruby?

Question

def class A
  def a
    raise \"hi\" #can\'t be reached
  end

  class B
    def b
      a() #doesn\'t find method a.
    end
  end
end

I want to invok

Answer 1

Well depending on your circumstances there is actually a solution, a pretty easy one at that. Ruby allows the catching of method calls that aren't captured by the object. So for your example you could do:

def class A
  def a
    raise "hi" #can't be reached
  end

  class B
    def initialize()
      @parent = A.new
    end

    def b
      a() #does find method a.
    end

    def method_missing(*args)
      if @parent.respond_to?(method)
        @parent.send(*args)
      else
        super
      end
    end
  end
end

So then if you do this:

A::B.new().b

you get:

!! #

It is probably an easier way to make something like a SubController that only handles certain activities, but can easily call basic controller methods (You would want to send in the parent controller as an argument in the initializer though).

Obviously this should be used sparingly, and it can really get confusing if you use it all over the place, but it can be really great to simplify your code.