Question

So I want a module with a variable and access methods.
My code looks something like this

module Certificates
  module Defaults

  class << self
    attr_accessor :address

    def get_defaults
      address = "something"
      make_root_cert
    end

    def make_root_cert
      blub = address
      # do somthing
    end
  end
end

I inspected it with pry.
The result is

• Certificates::Defaults has methods called address and address=.
• If I call address in the get_defaults method it returns “something” as expected
• If I call it in make_root_cert it returns nil

I used this way of attr_accessor creation in another module and it worked fine. I hope I’m just misunderstanding the way ruby works and somebody can explain why this example doesn’t work. Maybe using the implementation details of the ruby object model.

Jeremy is right.

My findings

This seems inconsistent to me.

• If you use the expression “address” and the instance variable has not been set it returns the local variable
• If the instance variable has been set and the local variable not it returns the instance variable.
• If both have been set it returns the local variable.

On the other hand address=”test” always sets the local variable.

Answer 1

In your get_defaults methods, address is a local variable. To use the setter, you have to type this:

self.address = "something"

That will properly call the address= method.