This could be a dumb question:
Is there a way we can evaluate a dynamic XPath like:
<xsl:if test="$tagPath = 'actual value'">
The tagPath is something like "//root/tag1/tag2"

Seems we can not do it with XSLT 1.0, right?

No, you can't do that with vanilla XSLT 1.0 (as others have
pointed out).

However, one solution is to cascade your stylesheets.
Have the first stylesheet write another stylesheet where
tagPath has been resolved, and then transform the source document
with the generated stylesheet.

HTHs,
Steve Ball

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