new XPath(testPathToAddition, eventSrcElement.getName());
// If the above path matches our own path for mapping from
// source (in the sense of source/target pair) to TARGET, then
// it's established that the EVENT source is indeed a target
if (testPathToEventSrc.externalFormsEqual(sourceToTargetPath)) {
// Target addition: make sure we don't already have one
if (existingProxyTarget != null) {
throw new IllegalStateException("Double target");
}