Re: A different comment syntax question

Chris Maden (crism@oreilly.com)
Fri, 17 Jul 1998 12:16:42 -0400 (EDT)

[Rob Cameron]
> Although the XML specification makes clear that "--" is not allowed
> in comments, there is another case that is less clear. Can the body
> of a comment end in a single hyphen, that is, is a comment like
> "<--A+, A or A--->" legal? There is no explicit mention of this in
> the text of the specification, but a careful read of the grammar
> does not allow it.

Correct. The production reflects the SGML reality that -- ends a
comment. In SGML terms:

'<!' starts the comment declaration in your example.
'--' starts the comment.
'A+, A or A' is the content of the comment.
'--' ends the comment.
'-' is an error.
'>' could be considered to end the comment declaration, but
we're now in error-recovery mode, and outside the scope
of the specification.

<!--A+, A or A- --> is a legal comment.

-Chris

-- 
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<!ENTITY crism PUBLIC "-//O'Reilly//NONSGML Christopher R. Maden//EN"
"<URL>http://www.oreilly.com/people/staff/crism/ <TEL>+1.617.499.7487
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