<br><font size=2 face="sans-serif">Let me start answering my own question
by way of these two definitions found in the XSD spec:</font>
<br>
<br><font size=3>The </font><a href="http://www.w3.org/TR/xmlschema-2/#dt-value-space"><font size=3 color=blue><u>ˇvalue
spaceˇ</u></font></a><font size=3> of <b>hexBinary</b> is the set of finite-length
sequences of binary octets. </font>
<br>
<br><font size=3>The </font><a href="http://www.w3.org/TR/xmlschema-2/#dt-value-space"><font size=3 color=blue><u>ˇvalue
spaceˇ</u></font></a><font size=3> of <b>base64Binary</b> is the set of
finite-length sequences of binary octets. </font>
<br>
<br><font size=2 face="sans-serif">Note that the value of these is not
some sort of encoded string form. I.e., hexBinary values do not involve
characters 0-9A-F, rather. It's the octets that are the value.</font>
<br>
<br><font size=2 face="sans-serif">To me this means that hexBinary and
base64Binary are really identical in DFDL, except if we provide some sort
of expressions for converting them to/from strings in that case the conversions
are different and produce/consume different strings. </font>
<br>
<br><font size=2 face="sans-serif">...mike<br>
<br>
</font>
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<td width=40%><font size=1 face="sans-serif"><b>Mike Beckerle/Worcester/IBM@IBMUS</b>
</font>
<br><font size=1 face="sans-serif">Sent by: dfdl-wg-bounces@ogf.org</font>
<p><font size=1 face="sans-serif">11/16/2007 04:23 PM</font>
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<div align=right><font size=1 face="sans-serif">To</font></div>
<td><font size=1 face="sans-serif">dfdl-wg@ogf.org</font>
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<td>
<div align=right><font size=1 face="sans-serif">cc</font></div>
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<div align=right><font size=1 face="sans-serif">Subject</font></div>
<td><font size=1 face="sans-serif">[DFDL-WG] DFDL infoset and hexBinary</font></table>
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<br><font size=2 face="sans-serif"><br>
What is the DFDL infoset value for a hexBinary type element?</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
Our doc says an element of type hexBinary has a value member in the infoset
whose type is a hexBinary, but what is a hexBinary anyway?</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
Consider this 12 bytes of data, dumped here as hex: 003100320033004100420043</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
If that's a string in UTF-16BE encoding, it looks like "123ABC"</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
It is 12 bytes long. </font><font size=3><br>
</font><font size=2 face="sans-serif"><br>
Suppose we describe this using this DFDL:</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
<element name="a" type="hexBinary" length='12' /></font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
As I understand it, this is correct XSD in that the length of a hexBinary
is always specified as the number of 'octets' of the binary data, not characters.
</font><font size=3><br>
</font><font size=2 face="sans-serif"><br>
Now, the contents of the basic XML infoset for an element matching this
schema are these 24 characters: "003100320033004100420043".
This is because the XML infoset has no idea what this string is because
it is not schema aware. </font><font size=3><br>
</font><font size=2 face="sans-serif"><br>
An XML document corresponding to this might look like:</font><font size=3>
<br>
</font><font size=2 face="sans-serif"><br>
<! xml version='1.0' encoding="UTF-16BE" !></font><font size=3>
</font><font size=2 face="sans-serif"><br>
<a>003100320033004100420043</a></font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
So, the question is......</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
What are the contents of the DFDL Infoset for a hexBinary like this? Same
24 characters? or 12 'octets' of data?</font><font size=3> <br>
</font><font size=2 face="sans-serif"><br>
This is essentially the answer to the question "what IS a hexBinary?"
or maybe "what is a hexBinary in the PSVI other than just a string?"</font><font size=3>
<br>
<br>
</font><font size=2 face="sans-serif"><br>
...mikeb</font><font size=3> </font><tt><font size=2>--<br>
dfdl-wg mailing list<br>
dfdl-wg@ogf.org<br>
http://www.ogf.org/mailman/listinfo/dfdl-wg</font></tt>
<br>