// relative URI into an absolute URI.
XObject arg2 = arg1Expr.execute(xctxt);
if (XObject.CLASS_NODESET == arg2.getType())
{
int baseNode = arg2.iter().nextNode();
if (baseNode == DTM.NULL)
warn(xctxt, XSLTErrorResources.WG_EMPTY_SECOND_ARG, null);
DTM baseDTM = xctxt.getDTM(baseNode);