pub fn lang<N: DomNavigator>(
context: &mut DynamicContext<'_, N>,
args: Vec<XPathValue<N>>,
) -> Result<XPathValue<N>, XPathError>Expand description
Implements fn:lang - tests whether a node’s language matches.
Walks up ancestors to find xml:lang attribute. Matching is case-insensitive with subtag support (“en” matches “en-US”).