Useful functions: text(), count(), contains(), starts-with(), concat(), string-length().
Going deeper
In production XML work, XPath functions matters when documents, stylesheets, or apps must stay maintainable across teams and releases—not only in isolated demos.
Common pitfalls
Watch for copy-paste configs, skipping validation or tests, and mixing concerns (structure vs presentation vs behavior) in one layer.
Practice
- Apply one technique from this lesson in the playground.
- Write one interview-style sentence explaining when you would use xpath functions on a real project.