All, I have a question regarding some of the contextual rules in RFC5892. For example the contextual rule in appendix A.4 Greek Lower Numeral Sign (U+0375), states the following:
If Script(After(cp)) .eq. Greek Then True; If the Greek Lower Numeral Sign (U+0375) is the last code point in the IDN, should it be allowed? There are statements in the RFC5892 as follows: Before(FirstChar) evaluates to Undefined. After(LastChar) evaluates to Undefined. Can I assume that "Undefined" is not equal to "Greek", and therefore input sequences with a trailing Greek Lower Numeral Sign are always disallowed by the specification? The Hebrew Punctuation Geresh (U+05F3), Hebrew Puncutation Gershayim (U+05F4), etc. also pose a similar question. The rule set for these contextual rules states the following: If Script(Before(cp)) .eq. Hebrew Then True; So, if the first code point is U+05F3, then should it be disallowed as there is no code point before this one to assert that it belongs to the Hebrew script. Regards, Nagesh Chigurupati