new CompositeArcsInOutEnumeratorImpl(this, aSource, CompositeArcsInOutEnumeratorImpl::eArcsOut);
new CompositeArcsInOutEnumeratorImpl(this, aSource, CompositeArcsInOutEnumeratorImpl::eArcsOut, mAllowNegativeAssertions, mCoalesceDuplicateArcs);
CompositeDataSourceImpl::ArcLabelsOut(nsIRDFResource* aSource,                                      nsISimpleEnumerator** aResult){    NS_PRECONDITION(aSource != nsnull, "null ptr");    if (! aSource)        return NS_ERROR_NULL_POINTER;    NS_PRECONDITION(aResult != nsnull, "null ptr");    if (! aResult)        return NS_ERROR_NULL_POINTER;    nsISimpleEnumerator* result =        new CompositeArcsInOutEnumeratorImpl(this, aSource, CompositeArcsInOutEnumeratorImpl::eArcsOut);    if (! result)        return NS_ERROR_OUT_OF_MEMORY;    NS_ADDREF(result);    *aResult = result;    return NS_OK;}