Question

Could anybody give an example when xsl:foreach is really useful?

I just made a project and concluded that everywhere I could replace it with appropriate <xsl:apply-templates />. <xsl:if> and <xsl:when/> sometimes make code shorter and i cannot effectively replace it with <apply-templates/> in functional style.

Is <xsl:foreach> considered harmful anyway?

Well, thanks everybody, i really couldn’t choose the answer among the best. i think it would be better to collect different cases.

Sorry for somebody downvoting answers – it’s not me:)

Answer 1

Using <xsl:for-each> is in no way harmful if one knows exactly how an <xsl:for-each> is processed.

The trouble is that a lot of newcomers to XSLT that have experience in imperative programming take <xsl:for-each> as a substitute of a ‘loop’ in their favorite PL and think that it allows them to perform the impossible — like incrementing a counter or any other modification of an already defined <xsl:variable>.

One indispensable use of <xsl:for-each> is to change the current document — this is often needed in order to be able to use the key() function on a document, different from the current source XML document, for example to efficiently access lookup-table that resides in its own xml document.