Here is my personal comments about
http://www.w3.org/TR/xml11/
"Extensible Markup Language (XML) 1.1
W3C Candidate Recommendation 15 October 2002"
1. in 2.2 Characters, you exclude characters U+FFFE and U+FFFF
according to Unicode 3.1, the list of non characters are extended
see
Noncharacters
There are 34 specific code points in Unicode 3.0 that are characterized as noncharacters. Unicode 3.1 adds an additional 32 noncharacters. To clarify the status of all 66, a definition (page 41) is added, and conformance rules C5 and C10 (pages 38, 39) are amended as follows:
D7b Noncharacter: a code point that is permanently reserved for internal use, and that should never be interchanged. In Unicode 3.1, these consist of the values U+nFFFE and U+nFFFF (where n is from 0 to 1016) and the values U+FDD0..U+FDEF.
- For more information, see the discussions under "Special Noncharacter Values" in Section 2.7, Special Character and Noncharacter Values, and under "Noncharacters" in Section 13.6, Specials.
- These code points are permanently reserved as noncharacters. In the future, it is possible that additional code points may be specified to represent noncharacters.
C5 A process shall not interpret either U+FFFE or U+FFFFa noncharacter code point as an abstract character.
- The code points may be used internally, such as for sentinel values or delimiters, but should not be exchanged publicly.
C10 A process shall make no change in a valid coded character representation other than the possible replacement of character sequences by their canonical-equivalent sequences or the deletion of noncharacter code points, if that process purports not to modify the interpretation of that coded character sequence.
- If a noncharacter which does not have a specific internal use is unexpectedly encountered in processing, an implementation may signal an error or delete or ignore the noncharacter. If these options are not taken, the noncharacter should be treated as an unassigned code point. For example, an API that returned a character property value for a noncharacter would return the same value as the default value for an unassigned code point.
in the http://www.unicode.org/reports/tr27/
Therefore, should the following session changed from
| [2] | Char |
::= | #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] | [#x10000-#x10FFFF] |
/* any Unicode character, excluding the surrogate blocks, FFFE, and FFFF. */ |
| [2] | Char |
::= | #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFDCF]
| [#xFDF0-#xFFFD] | [#x10000-#x1FFFD] | [#x20000-#x2FFFD]
| [#x30000-#x3FFFD] |
[#x40000-#x4FFFD] | [#x50000-#x5FFFD] |
[#x60000-#x6FFFD] | [#x70000-#x7FFFD] |
[#x80000-#x8FFFD] |
[#x90000-#x9FFFD] | [#xA0000-#xAFFFD]
| [#xB0000-#xBFFFD] | [#xC0000-#xCFFFD]
| [#xD0000-#xDFFFD] | [#xE0000-#xEFFFD]
| [#xF0000-#xFFFFD] |
[#x10000-#x1FFFD] |
/* any Unicode character, excluding the surrogate blocks, FDD0 to FDEF nFFFE, and nFFFF. */ |
2. similar thing should apply to
[4] NameStartChar
#xFDD0-#xFDEF should not be allowed in NameStartChar
nFFFE nor nFFFF should not be allowed in NameStartChar neither
It looks the NameStartChar do not allow private use area [#xE000-#xF8FF]. If we follow that principal, then [#xF0000-#x10FFFF] should neither be in NameStartChar since http://www.unicode.org/Public/3.2-Update/Blocks-3.2.0.txt defined them as Supplementary Private Use Area
F0000..FFFFF; Supplementary Private Use Area-A 100000..10FFFF; Supplementary Private Use Area-BAlso, I doubt we should allow
E0000..E007F; Tagsto be used as NameStartChar
Frank Yung-Fong Tang
