• From: Amelia A Lewis <amyzing@t...>
• To: "xml-dev@l..." <xml-dev@l...>
• Date: Fri, 28 Apr 2017 14:36:40 -0400

It's possibly worth adding production 66 and the Well-formedness 
constraint that bounds it:

Character Reference
[66]   CharRef ::= '&#' [0-9]+ ';'
                   | '&#x' [0-9a-fA-F]+ ';' [WFC: Legal Character]

Well-formedness constraint: Legal Character
Characters referred to using character references must match the 
production for Char.

So although the production permits � , the well-formedness 
constraint points back to production [2], Char, which John supplies, 
and which disallows all values below 32 except 9, 10, 13, and 32 itself.

Amy!
On Fri, 28 Apr 2017 12:31:34 -0400, John Cowan wrote:
> On Fri, Apr 28, 2017 at 3:18 AM, Mukul Gandhi <gandhi.mukul@g...>
> wrote:
> 
> I've just checked the Char production of XML, and it allows the existence
>> of Unicode code point for NUL character (i.e "\u0000").
> 
> 
> Actually, the production says:
> 
> Char   ::=   #x9 | #xA | #xD | [#x20-#xD7FF] | [#xE000-#xFFFD] |
> [#x10000-#x10FFFF] /* any Unicode character, excluding the surrogate
> blocks, FFFE, and FFFF. */
> 
> The comment is inaccurate:  #x0 is definitely not included.  Note that
> "\u0000" works in XML content because "\" has no special meaning in XML, so
> that is just six legal characters.  XML 1.1 allows a larger range of
> characters than XML 1.0, but still definitely excludes #0.
> 
> -- 
> John Cowan          http://vrici.lojban.org/~cowan        cowan@c...
> Where the wombat has walked, it will inevitably walk again.
>    (even through brick walls!)

• Follow-Ups:
  • Re: Proposed requirements on solutions that convertXML-illegal characters into XML
    • From: John Cowan <johnwcowan@g...>

• References:
  • Proposed requirements on solutions that convert XML-illegalcharacters into XML
    • From: "Costello, Roger L." <costello@m...>
  • Re: Proposed requirements on solutions that convertXML-illegal characters into XML
    • From: Timothy Cook <timothywayne.cook@g...>
  • Re: Proposed requirements on solutions that convertXML-illegal characters into XML
    • From: Mukul Gandhi <gandhi.mukul@g...>
  • Re: Proposed requirements on solutions that convertXML-illegal characters into XML
    • From: Mukul Gandhi <gandhi.mukul@g...>
  • Re: Proposed requirements on solutions that convertXML-illegal characters into XML
    • From: Timothy Cook <timothywayne.cook@g...>
  • Re: Proposed requirements on solutions that convertXML-illegal characters into XML
    • From: Mukul Gandhi <gandhi.mukul@g...>
  • Re: Proposed requirements on solutions that convertXML-illegal characters into XML
    • From: John Cowan <johnwcowan@g...>