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There are mutliple ways to convert EAD documents from an SGML/XML
encoding into an HTML encoding.

Methods that I have seen include perl scripts (Berkeley, RLG), Word
macros (Minnesota Historical Society did this for a while), and XSL
(Minn Historical Society currently).   Others will no doubt chime in.
There are also server-side transformations in PAT, OpenText and DynaWeb
of course.

One of the stated purposes of the Extensible Style Language (XSL) is to
be able to do simple transformations from one encoding scheme to
another.    For example you could transform  a file encoded in the MARC
DTD into EAD.   One of the most obvious transformations would be from
EAD to HTML so as to be able to deliver a file to older browsers.  For
more information on XSL see the World Wide Web Consortium site at
www.w3.org.

The drawback with XSL is that the standard has not been finalized.   The
first version was issued as what the W3C calls a "Note" on 8/27/97.  You
might consider this as the "Alpha" verison of XSL.  A number of products
were developed that worked with this "version" of XSL including the XSL
Styler, a free authoring tool from ArborText, and the MSXSL processing
engine, a free "technology preview" from Microsoft that accomplished XML
to HTML transformations.   A java application that runs as a DOS command
line application, msxsl.exe required Internet Explorer 4.0 (or at least
the version of the java virtual engine associated with IE 4).    Many of
the books that you see on the marketplace today that discuss XSL, do so
with respect to the syntax of the 8/27/97 version.   Stylesheet written
in this syntax are, of course, themselves XML documents.    Their syntax
is instantly recognizable as the stylesheet consists of a series of
rules that are embedded in <rule>....</rule> elements.


On August 8, 1998, the W3C issued the first Working Draft of XSL,
"Working Draft" being the next stage in the W3C review process.  Think
of it perhaps as the first Beta release.  The announced timetable was
that there will be three Working Drafts before the final format of
version 1.0 would go for balloting as a formal "Recommendation" in the
summer of 1999.   HTML and XML are W3C "Recommendations."    The Working
Draft made several major changes to the syntax, though not the
underlying intent or structure, of  XSL.   The changes are easy to spot
visually-  the <rule> element has been replaced by the <xsl:template>
element.  The enitre syntax of the elements and pattern matching has
changed, in part it appears, top conform to the xml:namespace
conventions.   Many parts of the specification were not finalized as of
the 8/28/98 release and the document includes notes at locations in the
text where future modifications might be made.   The next relase was
scheduled for November 1998 but obviously has not yet appeared.  (The
August release was scheduled for July so it may be forthcoming shortly).


The only tool of which I am aware that handles transformations using the
syntax of the 8/28/98 is the Koala xsl processo, available at

http://www.inria.fr/koala/XML/xslProcessor/

As the notes at this site indicate, Koala does not support all aspects
of XSL.   The msxsl processor does not work with the 8/28/98 syntax.


Microsoft has embedded a new version of its XSL processor within the 5.0
Beta version of its Internet Explorer browser.   The Microsoft XML site
describes its features and the syntax employed.   It appears that
Microsoft, as a member of the W3C, has already incorporated into this
software changes to XSL that will appear in the forthcoming release.
Someone with IE  5.0 can view an XML file in the browser using an XSL
stylesheet without the creator having to do an XML to HTML
transformation in advance.   The HTML is actually hidden from the user.
When you go to View Source, you see the XML code.   If you are using the
IIS http server to generate active server pages, the html output can be
created on the server side and presumably sent to any browser.
Unfortunately the old msxsl processor does not work if IE 5.0 is loaded
on your machine.

Back to the use part.  The Minnesota Historical Society has been using
the msxsl processor for some time to transform our EAD files, which we
create as XML instances, into HTML encoded files for delivery from our
Web site- principally through links from our MARC records.  The style
sheet is very specific to the format of our particular presentation of
finding aids.   With that caveat and with the understanding that the
code employed is out of date, we would be willing to make it available
through the EAD Roundtable Web site.

We are currently in the process of converting the stylesheet to the most
recent syntax but want to wait until it is formally released.   We have
reverse-engineered a version based on what Microsoft has released to
date that does work in IE 5.0 but I doubt that it is a very elegant
implementation.   Yes, EAD direct to your browser with no plug-ins.

Michael


Michael Fox
Head of Processing
Minnesota Historical Society
345 Kellogg Blvd West
St. Paul MN 55102-1906
phone: 651-296-1014
fax:  651-296-9961
[log in to unmask]
**NOTE NEW AREA CODE EFFECTIVE JULY 12, 1998**

Michael Fox
Head of Processing
Minnesota Historical Society
345 Kellogg Blvd West
St. Paul MN 55102-1906
phone: 651-296-1014
fax:  651-296-9961
[log in to unmask]
**NOTE NEW AREA CODE EFFECTIVE JULY 12, 1998**