Re: Question: Fullwidth double-quote and fullwidth backslash
[email protected] (Claus Färber)
| Newsgroups | gmane.ietf.imaa |
|---|---|
| Message-ID | <[email protected]> |
Simon Josefsson <[email protected]> schrieb/wrote: > [email protected] (Claus Färber) writes: >> Just do a NFKC normalisation at the very beginning and then additinally >> map U+3002 to U+002E. This will handle all of these special cases. > Doing normalization before mapping goes against stringprep and results > in different behaviour (see the "self reverting" test vectors on > <http://www.gnu.org/software/libidn/draft-josefsson-idn-test-vectors.html>). It does not if you do the normalisation twice (at the very beginning and after mapping). For IMAA, it suffices to specify that implementations MUST accept all characters as delimiters that decompose to one of our delimiters during NFKC-with-U+3002-to-U+002E normalisation and that the delimiters MUST be normalised. The easiest way to implement this is an additional normalisation at the very beginning. IDNA can get away wihtout such a normalisation because they have a single delimiter (U+002E) in their output. The IDNA processing maps all dot variants (including U+3002 and the width variants) to whatever delimiter is used (usually a dot U+002E or, in DNS packets, no delimiter at all). Claus -- http://www.faerber.muc.de/