[XML-SIG] Useless fun thing for XML - comments or helpers?
Sean Mc Grath
Thu, 3 Sep 1998 15:41:03 +0100
A couple of things.
1) XML is case sensitive. How about lowercase or CamelCase for the element
2) The characters "<" and "&" are special in XML and must be escaped if they
occur as part of the content (in URL's for example you can have "&").
This does not effect your DTD, but needs to be born in mind when generating
XBEL files. "&" -> "&". "<" -> "<"
3) In XML there are no standard ways of specifying lexical structure in
PCDATA (yet). Attributes give better (but still unsatisfactory) control.
I am thinking primarily of the date element type.
<date yyyy = "2005" mm = "12" dd = "01"/>
is more checkable than
4) There are many, many ways to go from XBEL to HTML and other formats:-
DSSSL Stylesheet (James Clark's Jade)
XSL StyleSheet (James Clark's XT via JPython)
Custom Python Translator
5) There is a lot of stuff going on in XML at the moment that will all
impact on XBEL as it develops:-
a) Rendering via XSL
b) Hypertext linking via XLink
c) Namespaces (making the vocabulary of XBEL formally public and documented
via a DTD)
d) DCD - A proposal for a more powerful schema language for XML than DTDs
I suggest we keep it all very simple for now! Even as it stands a tool like
sgrep - structured grepping - really shows up the advantage of XBEL.
><!-- DTD for XBEL - XML Bookmark Exchange Language -->
><!ELEMENT XBEL (INFO, NODE+)>
><!ELEMENT NODE (NAME, BOOKMARK+)>
><!ELEMENT BOOKMARK (NAME, URL)>
><!ELEMENT INFO (OWNER, MACHINE, VERSION, DATE?)>
><!ELEMENT OWNER (#PCDATA)>
><!ELEMENT MACHINE (#PCDATA)>
><!ELEMENT VERSION (#PCDATA)>
><!ELEMENT DATE (#PCDATA)>
><!ELEMENT NAME (#PCDATA)>
><!ELEMENT URL (#PCDATA)>
Sean Mc Grath - http://www.digitome.com/sean.htm
XML by Example:Building E-Commerce Applications
ParseMe.1st - SGML for Software Developers