At 00:21 08/05/13, Phillips, Addison wrote: >"Programming into implementations" information about which extlang subtags >can be used as primary language subtags requires a table of items from the >registry. Implementations that rely on remove-from-right solely (i.e. >"well-formed" implementations, as opposed to "validating" implementations) >will not have this information and will get it wrong. [as a technical contributor, just thinking out loud] I'm sure I forgot a lot of details, but it looks to me as if using extlangs is a tiny bit better in this respect. What I mean is that with something like zh-yue-Hant-hk or so, the simple remove-from-right procedure would give fallbacks of: zh-yue-Hant zh-yue zh It is my understanding that one of the arguments against exlangs was that the following fallbacks would be more natular: zh-yue-Hant zh-Hant **** zh Having the relevant subtags in the tag might allow something lik "remove-from-right+extlang", where we would have fallbacks of: zh-yue-Hant zh-yue ** zh-Hant ** zh or something similar. The relative order between zh-yue and zh-Hant may need to be defined, or there may not be such a need because we may be able to assume that for any single document (or other matching target), we would not have zh-yue and zh-Hant at the same time. This wouldn't work with existing implementations, but it might work with newer implementations. On the other hand, it would NOT create a dependency on checking the registry to see that zh is a fallback (or whatever we call it) for yue. Again, for the moment, just thinking out loud. Regards, Martin. #-#-# Martin J. Du"rst, Assoc. Professor, Aoyama Gakuin University #-#-# http://www.sw.it.aoyama.ac.jp mailto:duerst at it.aoyama.ac.jp _______________________________________________ Ltru mailing list Ltru at ietf.org https://www.ietf.org/mailman/listinfo/ltru
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