# File lib/yaml/rubytypes.rb, line 278
        def to_yaml( opts = {} )
                YAML::quick_emit( nil, opts ) do |out|
            if to_yaml_properties.empty?
                out.scalar( taguri, self.inspect, :plain )
            else
                out.map( taguri, to_yaml_style ) do |map|
                    src = self.inspect
                    if src =~ /\A\/(.*)\/([a-z]*)\Z/
                        map.add( 'regexp', $1 )
                        map.add( 'mods', $2 )
                    else
                                raise YAML::TypeError, "Invalid Regular expression: " + src
                    end
                    to_yaml_properties.each do |m|
                        map.add( m, instance_variable_get( m ) )
                    end
                end
            end
        end
        end