method
mattr_accessor

mattr_accessor(*syms)
public
Extends the module object with module and instance accessors for class attributes, just like the native attr* accessors for instance attributes.
module AppConfiguration mattr_accessor :google_api_key self.google_api_key = "123456789" mattr_accessor :paypal_url self.paypal_url = "www.sandbox.paypal.com" end AppConfiguration.google_api_key = "overriding the api key!"
To opt out of the instance writer method, pass :instance_writer => false. To opt out of the instance reader method, pass :instance_reader => false. To opt out of both instance methods, pass :instance_accessor => false.