2.3 Is undefined formally defined? This section suggests that 'undef' or 'null', inter alia, may be used to undefine a variable while 3.2 uses 'null'. I see no more formal definition of how to undefine a variable, as opposed to it having a value or having an empty value. 1.2 worth pointing out that 'reserved' and 'unreserved' are formally defined in 1.5, to stop people reaching for RFC3986. The examples are rather complicated. If I have a month to spare, I will work my way through them by which time, were I to find anything, doubtless it would be erratum time and no longer LC time. (How simple life was in the days of -00). Tom Petch _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf