diff options
| -rw-r--r-- | src/Storage/Merge.hs | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/src/Storage/Merge.hs b/src/Storage/Merge.hs index e9cb3d7..a6ed3ba 100644 --- a/src/Storage/Merge.hs +++ b/src/Storage/Merge.hs @@ -94,12 +94,17 @@ ancestors :: Storable a => [Stored a] -> Set (Stored a) ancestors = last . (S.empty:) . generations precedes :: Storable a => Stored a -> Stored a -> Bool -precedes x y = x `S.member` ancestors [y] +precedes x y = not $ x `elem` filterAncestors [x, y] filterAncestors :: Storable a => [Stored a] -> [Stored a] filterAncestors [x] = [x] -filterAncestors xs = uniq $ sort $ filter (`S.notMember` ancestors xs) xs - +filterAncestors xs = let xs' = uniq $ sort xs + in helper xs' xs' + where helper remains walk = case generationMax walk of + Just x -> let px = previous x + remains' = filter (\r -> all (/=r) px) remains + in helper remains' $ uniq $ sort (px ++ filter (/=x) walk) + Nothing -> remains findProperty :: forall a b. Storable a => (a -> Maybe b) -> [Stored a] -> [b] findProperty sel = map (fromJust . sel . fromStored) . filterAncestors . (findPropHeads =<<) |