XML/XQuery/is

Testing for the last car using the is operator

File: Data.xml

<order>
  <car model="A">
    <name language="en">name 1</name>
  </car>
  <car model="B">
    <name language="en">name 2</name>
  </car>
  <car model="B">
    <name language="en">name 3</name>
  </car>
</order>

File: Query.xquery
<p>{ let $prods := doc("Data.xml")//car
     for $prod in $prods
     return if ($prod is $prods[last()])
            then concat($prod/name,".")
            else concat($prod/name,", ")
}</p>
Output:
<?xml version="1.0" encoding="UTF-8"?>
<p>name 1,  name 2,  name 3.</p>