Nagesh Chigurupati asked: > 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?
Correct. > 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 Correct. > as > there is no code point before this one to assert that it belongs to the > Hebrew script. Although the reasoning there is incorrect. The script of U+05F3 and U+05F4 is Hebrew already. It isn't a matter of a lack of a previous character to assert this. Rather, the RFC 5892 specification simply states that U+05F3 and U+05F4 are only allowed immediately following a(nother) Hebrew character in a label. --Ken
