final InvokeResult r = (InvokeResult)elem;
final InvokeResult.ResultType result = r.getResultType();
// don't output "not found" results; only those that
// were invoked and succeeded or failed
if ( result == InvokeResult.SUCCESS ||
result == InvokeResult.FAILURE )
{
buf.append( mElementStringifier.stringify( elem ) );
buf.append( delim );
}