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There will be many occasions while programming in XSLT where you have a long xpath, or you're inside a template and have a relative set of elements that you want to test for a specific condition. The idea of doing an xsl:for-each in order to find a specific element is an overkill (since you cannot break out of a loop in xslt) and in this article we will see how we can avoid that using the double negation trick.
I've recently been asked by a friend to explain the difference between include and import and how it would affect the templates being matched in these files. The answer is very simple, but you also must understand that there are other ways to foce which template will be called in the case that were are identical matchings.
There is a common problem in XSLT where you have two XML of the same xPath (whether it be absolute or relative) that end up taking the same template. In many scenarios you do not have the ability to modify the XML so that it suits your XSLT and you must therefore turn to the mode trick to create seperate templates.