DTDs in XML (Clause 11)
Despite Michael's request that messages be kept to a single subject within
the list I have decided not to bombard you all with one message per point I
want to make, but have tried to cover questions raised by one of the set of
forms in one posting. This set of points relates to dd-1996-0002-f7.html,
which deals with DTDs.
This clause also contains (through a revision) a recommendation that all
attributes whose declared value is ID should have the same name. Does XML
want to enforce this horrible recommendation?
WG8 have agreed in principle that there can be more than one attlist
declaration for an element in future versions of SGML. It is possible that
there will be new rules about the interpretation of attlists in which the
same attribute name occurs in two declarations for a particular element.
As well as deciding whether or not #CONREF should be retained the XML review
process should also determine what is meant by #IMPLIED. Should it mean
inheritance (a la TEI) or a system defined default, or a random value
applied by the system? If inheritance is not accepted then we will need to
define #IMPLIED clearly enough to ensure that different plug-ins do not
assign different implied values. In particular the meaning of #IMPLIED with
respect to elements defined using ID as the default value needs to be
Remember that empty literals only apply when the attribute is of type CDATA.
It then has a very distinct meaning - an empty string. This is definitely
not the same as an implied value.
Martin Bryan, The SGML Centre, Churchdown, Glos. GL3 2PU, UK
Phone/Fax: +44 1452 714029 WWW home page: http://www.u-net.com/~sgml/