ElementParser.onXI

// Call this function whenever an XML instruction is encountered
// (Note: XML instructions may only occur preceding the root tag of a
// document).
onPI = (string s)
{
    // Your code here

    // The passed parameter s does not include the opening <! nor
    // closing >
    //
    // This is a a closure, so code here may reference
    // variables which are outside of this scope
};