xml-dev - RE: Unnecessary well-formedness constraint

["Hanson, Jon" <jhanson@lehman.com>]

i think the annotation is simple saying that something that looks like a
parameter entity such as %Fred; that appears outside of a DTD will simple be
interpreted as the text '%Fred;', not as a parameter entity.
hence the constraint is necessary, otherwise the expression would be a
parameter entity regardless of its context.

jon

> -----Original Message-----
> From:	Elliotte Rusty Harold [SMTP:elharo@metalab.unc.edu]
> Sent:	Thursday, October 12, 2000 8:38 PM
> To:	xml-dev
> Subject:	Unnecessary well-formedness constraint
> 
> Section 4-1 of the XML 1.0 second edition spec states:
> 
> 
> Well-Formedness Constraint: In DTD
> Parameter-entity references may only appear in the DTD.  
> 
> 
> The Annotated XML spec notes that:
> 
> This constraint is not actually wrong, but it is rather misleading.
> Suppose I have a parameter entity named Fred, then if the string %Fred;
> appears somewhere in the document, outside of the DTD, that's not an
> error as this suggests; it's just the string %Fred;.
> 
> So my question is why is this constraint here at all? What is its
> effect? If we removed it form the spec (say in the third edition) would
> this in any way change which document are considered to be well-formed
> or valid? Would removing it give parsers any leeway they don't have now?
> Right now this seems like an unnecessary statement to me. 
> 
> -- 
> +-----------------------+------------------------+-------------------+
> | Elliotte Rusty Harold | elharo@metalab.unc.edu | Writer/Programmer |
> +-----------------------+------------------------+-------------------+ 
> |               Java I/O (O'Reilly & Associates, 1999)               |
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