Function validate_one_node

src/xpath_functions.rs:59–66

make sure that there is only one node in the NodeSet Returns the node or an Error

(nodes: Nodeset<'n>, func_name: &str)

// make sure that there is only one node in the NodeSet
// Returns the node or an Error
pub fn validate_one_node<'n>(nodes: Nodeset<'n>, func_name: &str) -> Result<Node<'n>, Error> {
    if nodes.size() == 0 {
        return Err(Error::Other(format!("Missing argument for {}", func_name)));
    } else if nodes.size() > 1 {
        return Err( Error::Other(format!("{} arguments for {}; expected 1 argument", nodes.size(), func_name)) );
    }
    return Ok( nodes.iter().next().unwrap() );
}

// Return true if the element's name is 'name'
fn is_tag(e: Element, name: &str) -> bool {