@@ -152,11 +152,13 @@ vetTypos potentialTypos =
152152 (leftCounts, rightCounts) =
153153 foldr tallyNames (Map.empty, Map.empty) potentialTypos
154154
155− allUnique :: Map.Map String Int -> Bool
156− allUnique counts =
155+ acceptable :: Map.Map String Int -> Bool
156+ acceptable counts =
157+ not (Map.null counts)
158+ &&
157159 Map.foldr (\n unique -> n < 2 && unique) True counts
158160 in
159− if allUnique leftCounts && allUnique rightCounts then
161+ if acceptable leftCounts && acceptable rightCounts then
160162 Just (Map.keysSet leftCounts, Map.keysSet rightCounts)
161163
162164 else