Sample Metaprogramming

config_accessor.rb

module ConfigAccessor
  def self.included(base)
    base.extend(ClassMethods)
  end
  
  module ClassMethods 
   # Assumes config will be accessible like an attribute
   def config_accessor(config, attr)
    # Define reader
    define_method(attr) do 
     self.public_send(config)[attr]
    end
    
    # Define writer
    define_method("#{attr}=") do |v|
     self.public_send(config)[attr] = v
    end 
   end 
  end 
end

example.rb

class Example
 include ConfigAccessor
 
 attr_accessible :sample_config
 
 # Utilize the accessor provided by ConfigAccessor
 config_accessor :sample_config, :port
end