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Diffstat (limited to 'src/Erebos/Storage/Merge.hs')
| -rw-r--r-- | src/Erebos/Storage/Merge.hs | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/Erebos/Storage/Merge.hs b/src/Erebos/Storage/Merge.hs index 7234b87..9d9db13 100644 --- a/src/Erebos/Storage/Merge.hs +++ b/src/Erebos/Storage/Merge.hs @@ -10,6 +10,7 @@ module Erebos.Storage.Merge ( generations, ancestors, precedes, + precedesOrEquals, filterAncestors, storedRoots, walkAncestors, @@ -109,6 +110,9 @@ ancestors = last . (S.empty:) . generations precedes :: Storable a => Stored a -> Stored a -> Bool precedes x y = not $ x `elem` filterAncestors [x, y] +precedesOrEquals :: Storable a => Stored a -> Stored a -> Bool +precedesOrEquals x y = filterAncestors [ x, y ] == [ y ] + filterAncestors :: Storable a => [Stored a] -> [Stored a] filterAncestors [x] = [x] filterAncestors xs = let xs' = uniq $ sort xs |