# File lib/cgikit.rb, line 1228
        def retrieve_value( key )
                keypath = key.split '.'
                object  = self
                keypath.each do |path|
                        if object.respond_to? path then
                                object = object.__send__ path
                        elsif _directly?(object) == true then
                                object = object.instance_eval "@#{path}"
                        else
                                _raise_error(object, path)
                        end
                end
                object
        end