## Description ### Background In railML 2.x a signal can be linked with a rule book identifier using attribute @ruleCode. In railML 3.x the `@ruleCode` attribute is (so far) not modelled. ### Links * Forum discussion: * Torben Brand, 25.02.2020: https://www.railml.org/forum/index.php?t=msg&th=712&start=0& * Torben Brand, 18.03.2022: https://www.railml.org/forum/index.php?t=msg&th=712&goto=2967&#msg_2967 * Trac tickets * #443 * Wiki documentation * IS:signalIS: https://wiki3.railml.org/wiki/IS:signalIS ## Solution proposal railML 3.2 Option 1: implement missing attribute **`@ruleCode`** for signals (and other signalling related elements) Option 2: A new "designator-like" element is introduced with attributes `@rulebook` and `@entry`. This could be called **`<typeDesignator>`** Option 3: use already available child element **`<designator>`** to specify a rule code. _Update 18.03.2022: Option 2 has been marked as preferred solution. The `<typeDesignator>` shall be available for all functional infrastructure elements._