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Re: Be careful writing XPath expressions when the XML couldhav

• From: Benito van der Zander <benito@benibela.de>
• To: "Costello, Roger L." <costello@mitre.org>, xml-dev@l...
• Date: Wed, 30 Jul 2014 22:29:37 +0200

Hi Folks,

Are you writing XPath expressions?

XPath is embedded in a lot of things: XQuery, Schematron, XSLT, XML Schema. If you are using XML, there is a good chance you are writing XPath expressions.

Heads up!

Failure to take into account the following rule will result in countless headaches and hard-to-detect bugs.

	Rule: The result of evaluating an XPath expression
	that compares a non-existent element against
	anything is always false.

More ... http://xfront.com/Be-Careful-Writing-XPath-Expressions-Against-XML-Documents-that-may-have-Non-Existent-Elements.pdf

/Roger

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• References:
  • Be careful writing XPath expressions when the XML could havenon-existent elements
    • From: "Costello, Roger L." <costello@mitre.org>