} // endValueScopeFor(IdentityConstraint)
// a utility method for Identity constraints
private void activateSelectorFor(IdentityConstraint ic) {
Selector selector = ic.getSelector();
FieldActivator activator = this;
if (selector == null)
return;
XPathMatcher matcher = selector.createMatcher(activator, fElementDepth);
fMatcherStack.addMatcher(matcher);
matcher.startDocumentFragment();