Valid xpath from a XSD

Question

Given that one has a XSD A. One can then validate that file X is either valid or not based on that XSD.
What would be required to validate that a given Xpath is valid in terms of the XSD? Such that when used on file X that it is correct.
So given the following pseudo schema
  <xs:element name="Tag">
    <xs:complexType>
      <xs:choice minOccurs="1" maxOccurs="1">
        <xs:element name="InnerTag"/>
      </xs:choice>
    </xs:complexType>
  </xs:element>
A 'valid' xpath would be "//InnerTag". Where all of the following would be invalid:
    //OuterTag
    //innertag
    //InnerTag/Tag

Answer 1

I guess the problem is that there are several ways to write an XPath locating an individual node. For example, you may wish to use last() instead of explicitly specifying the index of the last node. Also, you may wish to include tag names in the XPath instead of using the generic *[3] style indexing.
You could easily write an XPath string generator yourself, custom-made for your particular needs.
Simply follow up the hierarchy working out the index of the current node (in relation to its siblings) as you go. Then you might end up with something like:
/*[2]/*[1]/*[3]