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Re: 3 Common Patterns in XML Processing

• From: Stephen Green <stephengreenubl@gmail.com>
• To: "xml-dev@lists.xml.org" <xml-dev@lists.xml.org>
• Date: Mon, 28 Feb 2011 10:02:00 +0000

One comment on lists:

Often it is not known whether an element can be a list. There might be
a schema associated with it which describes it having multiple
occurrences but sometimes this is either not known to the writer of
the code which handles that element or it is overlooked. e.g. if
<book> had the possibility of multiple <title> elements. It might be
very rare that there is ever a book/title[2] so the usual XPath used
in code might be book/title. This means that there will be rare
occasions when book/title returns a set of nodes rather than a single
node. It is a pain to always remember to write book/title[1] just in
case a list is involved and without a schema who would know to do that
anyway unless they do it for every XPath and cater for it in every bit
of code.

----
Stephen D Green

• References:
  • 3 Common Patterns in XML Processing
    • From: "Costello, Roger L." <costello@mitre.org>