Create a configuration class

config.rb

# Usage: 
#
# Settings.configure do |c| 
#   c.foo = "biz"
#   c.bar = "boo"
# end

# Test.config.foo
# => "biz" 
# Test.configured?
# => true 
# Test.reset!
# => nil 
# Test.configured?
# => false 
# Test.config.foo

class Settings
  def self.config
    @config ||= Struct.new(:foo, :bar).new
  end
  
  def self.configure
    yield(config)
  end
  
  def self.configured?
    !!@config 
  end
  
  def self.reset!
    @config = nil
  end
end