# File lib/cgikit.rb, line 1155
        def initialize( string = nil )
                @repetitions = []
                if string then
                        tokens     = string.split '.'
                        @component = tokens.shift
                        @element   = tokens.pop

                        # parses repetitions
                        token = repetition = nil
                        unless tokens.empty?
                                tokens.each do | token |
                                        repetition = token.split ':'
                                        @repetitions << [ repetition.first, repetition.last.to_i ]
                                end
                        end
                end
        end