At the time, I was just pleased to have got the XPath stuff done and wasn't really fussed, so I left it. Since then though, it's niggled and niggled away at the back of my mind and now I've decided to do something about it.
XPathValuePtr will become XPathValue, with the member functions accessed through the . operator. The XPathValuePtr name and -> member access will be retained for the meantime, so that existing code won't be broken. XPathExpressionPtr will be similarly changed.
This commit is the first bit of that work, now I've satisfied myself it's going to be pretty easy so long as I pay proper attention.