{ NS_ENSURE_ARG_POINTER(aCategoryName); NS_ENSURE_ARG_POINTER(_retval);
{ NS_ASSERTION(aCategoryName, "aCategoryName is NULL!"); NS_ASSERTION(_retval,       "_retval is NULL!");
nsCategoryManager::EnumerateCategory( const char *aCategoryName,                                      nsISimpleEnumerator **_retval ){  NS_ENSURE_ARG_POINTER(aCategoryName);  NS_ENSURE_ARG_POINTER(_retval);  PR_Lock(mLock);  CategoryNode* category = get_category(aCategoryName);  PR_Unlock(mLock);    if (!category) {    return NS_NewEmptyEnumerator(_retval);  }  return category->Enumerate(_retval);}