- the version of XML,
Not any more than Postscript 1 and Postscript 2 having separate versions.
- the version of Unicode,
Not for any other text type, why for XML?
- how the Private Use Area (PUA) of Unicode is used
[Rick Jelliffe wrote: "This also could have bearing on the PUA
(private use area) character problem, and the problem of corporate
character sets (e.g. Hong Kong's GCCS)."]
Using Private Use Area in Unicode is tantamount to using a private
charset.
Suggestion:
a) eliminate text/xml
b) eliminate 'charset' parameter from application/xml
The charset is self-identifying. If there is a PUA in use,
then it must be declared in the head of the XML body.
Having PUAs in your charset is like having a private use
font.
- which conversion table (Note: for a given CCS, more than one conversion
table may exist),
- which schema language is used (DTD or the upcoming schema language
from W3C),
- which stylesheet (XSL, CSS, DSSSL, etc.) is used, and
- other issues mentioned in my mail "List of issues".
Does anybody think that some of them are good enough reasons for introducing
top-level XML media types? (I am just asking.)
These are good reasons for making sure that this information is
self-identified in the head of the XML body.