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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>This may be a well-worn question. If so, please point me to
the location of the discussion. Otherwise. . .<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m thinking through the XQuery/XPath data model. The last
paragraph in section 3.0 has me puzzling: “</span></font><span lang=EN>The
data model also supports values that are not nodes. Examples of these are
sequences of <a
href="http://www.w3.org/TR/2007/REC-xpath-datamodel-20070123/#dt-atomic-value#dt-atomic-value"
title="atomic value">atomic values</a>, or sequences mixing nodes and atomic
values. These are necessary to be able to represent the results of intermediate
expressions in the data model during expression processing.</span><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>”<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I’m accustomed, from XPath 1.0, to thinking of
trees of nodes, so I’m not quite getting what it means to have items in
sequences that are either nodes or atomic values. Since an atomic value is a
string that conforms to an atomic type, atomic types are schema-defined, and nodes
may or may not have schema-defined datatypes, I don’t understand the case
where an atomic type would not be associated with – and so represented by
-- a node. In other words, I can’t image a XQuery/XPath sequence as
anything other than a node tree, which clearly shows I’m still in XPath 1.0
land.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The last line I quoted above indicates that this whole issue
arises from something that goes on during expression processing, so perhaps
this is an issue that only matters to those who write XQuery/XPath engines. At
any rate, if anyone can clarify this issue for me, I’d appreciate it.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Don Smith</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Information Architect<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>American Airlines<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>817-967-0310</span></font><o:p></o:p></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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