[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

Re: Parameter entities in internal subset

• From: "D. Burrowes" <biede0@gmail.com>
• To: Ronald Bourret <rpbourret@rpbourret.com>
• Date: Sun, 2 Dec 2018 19:53:45 -0800

Ron,

I happened to be searching for some info and stumbled across your email… almost a year late!  Thought I’d chime in since I saw no other responses.

The only way I’ve been able to make heads-or-tails of this is to interpret that the entity value as not quite IN an entity declaration (or, rather, it’s an opaque unit within the declaration).  That interpretation is, certainly a little bit convenient/contrived, but I suspect matches the intent.

As I see it, entity values seem to get a bit of special treatment here, since they allow parameter entities in them when other literals do not. Further, a parameter entity can’t (as far as I know) span the start of a literal.  That is, this doesn’t seem to be OK:
	<!ENTITY % outch 'foo “start’>
	<!ENTITY %outch; and end’>
I’ve always argued to myself that this violates some of the senses of things being properly nested (with the view that the literal’s open and close quotes together form a nestable unit), even though I don’t think this is stated in this case (there’s plenty of other places, though, that concern of nesting is stated).  So, with the notion that the entity value isn’t really a divisible unit here, I then extend my thinking to believe that its contents aren’t really IN the markup.

Sincerely (while doffing my apologist’s hat)

David


> On Jan 6, 2018, at 15:09, Ronald Bourret <rpbourret@rpbourret.com> wrote:
> 
> I haven't been here for quite a while, so hello to everyone.
> 
> As a way to learn git, I've been fixing some ancient bugs in my DTD Parser, and that has led me to the Joy of Entities. I understand the intent, but am missing a few details and the deeper I dig, the more my head spins.
> 
> Section 2.8 (Prolog and Document Type Declaration), has a well-formedness constraint: "PEs in Internal Subset: In the internal DTD subset, parameter-entity references must not occur within markup declarations"
> 
> Paragraph 2 of section 4.5 states, "The literal entity value as given in an internal entity declaration (EntityValue) may contain character, parameter-entity, and general-entity references" and goes on to state that parameter-entity references are replaced.
> 
> Since markup declarations include entity declarations, why doesn't section 4.5 contradict section 2.8?
> 
> Thanks,
> 
> -- Ron
> 
> _______________________________________________________________________
> 
> XML-DEV is a publicly archived, unmoderated list hosted by OASIS
> to support XML implementation and development. To minimize
> spam in the archives, you must subscribe before posting.
> 
> [Un]Subscribe/change address: http://www.oasis-open.org/mlmanage/
> Or unsubscribe: xml-dev-unsubscribe@lists.xml.org
> subscribe: xml-dev-subscribe@lists.xml.org
> List archive: http://lists.xml.org/archives/xml-dev/
> List Guidelines: http://www.oasis-open.org/maillists/guidelines.php