I would like to convert a string into a node. I have a method that is defined to take a node, but the value I have is a string (it is hard coded). How do I turn that string into a node?

So, given an XQuery method:

define function foo($bar as node()*) as node() {
  (: unimportant details :)
}

I have a string that I want to pass to the foo method. How do I convert the string to a node so that the method will accept the string.