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<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2>The nearest to a map() function is the "for"
expression</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2>count(distinct-values(for $x in //element(*,
xs:date) return timezone-from-date($x), </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff
size=2>
for $x in //element(*, xs:dateTime) return timezone-from-dateTime($x),
</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff
size=2>
for $x in //element(*, xs:time) return timezone-from-time($x))) eq
1</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2>But there is also the "simple mapping operator" "/"
-</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff
size=2>//element(*,xs:date)/timezone-from-date(.)</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2>It's rather tedious that there's no polymorphism (or
support of union types) so that the different date/time types have to be
enumerated like this.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2>Note that if a dateTime has no timezone,
timezone-from-dateTime() will return (), which is ignored in counting the
distinct values.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2>Michael Kay</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=635264111-12122008><FONT face=Arial
color=#0000ff size=2><A
href="http://www.saxonica.com/">http://www.saxonica.com/</A></FONT> </SPAN></DIV><BR>
<BLOCKQUOTE dir=ltr
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
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<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> talk-bounces@x-query.com
[mailto:talk-bounces@x-query.com] <B>On Behalf Of </B>Matthew
Rawlings<BR><B>Sent:</B> 12 December 2008 11:27<BR><B>To:</B>
talk@x-query.com<BR><B>Subject:</B> [xquery-talk] count all the distinct
timezones in an XML documentusing XPath<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV class=Section1>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">How can I count all the distinct
timezones in a single XML document using XPath?<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I have an XML document with many
elements and attributes with the type xs:date or xs:datetime. One of the rules
of the system receiving my document is that all timezones must be the same in
the document. Ideally I would like to express this constraint purely in XPath
2 rather than XQuery so I can put the constraint in a xs:assert
statement.<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">If there was a map function in
XPath I would write something like this:<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">count(distinct-values(map(fn:date-from-timezone(),
//(element(*, xs:date)|attribute(*, xs:date)|element(*,
xs:datetime)|attribute(*, xs:datetime))))) eq 1<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">This XPath would return true if
all timezones were the same, and false otherwise.<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">However there is no map function
in XPath, so how can I achieve the same thing without it? What is the nearest
I could get.<o:p></o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"><o:p> </o:p></SPAN></FONT></P>
<P class=MsoNormal><FONT face=Arial size=2><SPAN
style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">-
Matthew<o:p></o:p></SPAN></FONT></P></DIV></BLOCKQUOTE></BODY></HTML>