Re: Entity and Element Addressing
At 12:23 PM 1/28/97, Terry Allen wrote:
>I note from XML 1.0, s.v. 2.2, that in a well formed XML document,
>for each entity reference, the entity name must be declared in
>the doctype declaration (at that point, reference might be made
>to 2.9, in which the concept of internal and external subsets
>is introduced). S.v. 4.2.2, the system identifier
>must be a URL (should the sentence following the Validity
>Check following production 71 start "The SystemLiteral"?). It might
>be worth while pointing out that in xmllink, addressing by entity
>means addressing by URL using entities for indirection. Is
It doesn't say so, so I assume not. Nor does ENTITIES seem that it would be
useful in this case.
>| If the reference type is ELEMENT,
>| then the HREF must be the value of a unique identifier attribute within
>"Unique identifier attribute" isn't language I can find in XML 1.0.
>Is "ID value" intended? What of ELEMENTS, in the plural? (In other
>words, is this really IDREF/IDREFS?)
I think so, but the language should be changed.
We have also considered allowing references based on any attribute value --
this would be nice, but would need to be defined first.
>What happens when the system identifier for the entity already
>contains a #? What is the force of "leading" in "leading entity name"?
I don't think that this matters, actually. If the system identifier
identifies an XML document, then it presumably can't contain a '#', or it
contains a # with some fancy XML-linking query semantics, so that the IDREF
is applied relative to the result of following the pointer. Leading entity
name seems to mean that the entity name is first in a string like:
With the entity declaration
<!entity Foo SYSTEM "http://www.bar.com/bletch.xml">
Did I get the example right?
I am not a number. I am an undefined character.
David Durand firstname.lastname@example.org \ david@dynamicDiagrams.com
Boston University Computer Science \ Sr. Analyst
http://www.cs.bu.edu/students/grads/dgd/ \ Dynamic Diagrams
MAPA: mapping for the WWW \__________________________