def self.property(property_name, options = {})
property_name = property_name.to_sym
properties << property_name
if options.key?(:default)
defaults[property_name] = options[:default]
elsif defaults.key?(property_name)
defaults.delete property_name
end
unless instance_methods.map { |m| m.to_s }.include?("#{property_name}=")
define_method(property_name) { |&block| self.[](property_name.to_s, &block) }
property_assignment = property_name.to_s.concat('=').to_sym
define_method(property_assignment) { |value| self.[]=(property_name.to_s, value) }
end
if defined? @subclasses
@subclasses.each { |klass| klass.property(property_name, options) }
end
required_properties << property_name if options.delete(:required)
end