mirror of
https://github.com/hasura/graphql-engine.git
synced 2024-12-16 18:42:30 +03:00
05b3a64e8f
- Remove `onJust` in favor of the more general `for_` - Remove `withJust` which was used only once - Remove `hashNub` in favor of `Ord`-based `uniques` - Simplify some of the implementations in `Hasura.Prelude` - Add `hlint` hint from `maybe True` to `all`, and `maybe False` to `any` PR-URL: https://github.com/hasura/graphql-engine-mono/pull/6173 GitOrigin-RevId: 2c6ebbe2d04f60071d2a53a2d43c6d62dbc4b84e
61 lines
1.8 KiB
Haskell
61 lines
1.8 KiB
Haskell
module Data.List.Extended
|
|
( duplicates,
|
|
uniques,
|
|
getDifference,
|
|
getDifferenceOn,
|
|
getOverlapWith,
|
|
longestCommonPrefix,
|
|
appendToNonEmpty,
|
|
module L,
|
|
)
|
|
where
|
|
|
|
import Data.Containers.ListUtils (nubOrd)
|
|
import Data.Function (on)
|
|
import Data.HashMap.Strict.Extended qualified as Map
|
|
import Data.HashSet qualified as Set
|
|
import Data.Hashable (Hashable)
|
|
import Data.List qualified as L
|
|
import Data.List.NonEmpty qualified as NE
|
|
import Prelude
|
|
|
|
duplicates :: (Eq a, Hashable a) => [a] -> Set.HashSet a
|
|
duplicates =
|
|
Set.fromList . Map.keys . Map.filter (> 1) . Map.fromListWith (+) . map (,1 :: Int)
|
|
|
|
-- | Remove duplicates from a list. Like 'nub' but runs in @O(n * log(n))@
|
|
-- time and requires 'Ord' instances.
|
|
-- >>> uniques [1,3,2,9,4,1,5,7,3,3,1,2,5,4,3,2,1,0]
|
|
-- [0,1,2,3,4,5,7,9]
|
|
uniques :: (Ord a) => [a] -> [a]
|
|
uniques = nubOrd
|
|
|
|
getDifference :: (Eq a, Hashable a) => [a] -> [a] -> Set.HashSet a
|
|
getDifference = Set.difference `on` Set.fromList
|
|
|
|
getDifferenceOn :: (Eq k, Hashable k) => (v -> k) -> [v] -> [v] -> [v]
|
|
getDifferenceOn f l = Map.elems . Map.differenceOn f l
|
|
|
|
getOverlapWith :: (Eq k, Hashable k) => (v -> k) -> [v] -> [v] -> [(v, v)]
|
|
getOverlapWith getKey left right =
|
|
Map.elems $ Map.intersectionWith (,) (mkMap left) (mkMap right)
|
|
where
|
|
mkMap = Map.fromList . map (\v -> (getKey v, v))
|
|
|
|
-- | Returns the longest prefix common to all given lists. Returns an empty list on an empty list.
|
|
--
|
|
-- >>> longestCommonPrefix ["abcd", "abce", "abgh"]
|
|
-- "ab"
|
|
--
|
|
-- >>> longestCommonPrefix []
|
|
-- []
|
|
longestCommonPrefix :: Eq a => [[a]] -> [a]
|
|
longestCommonPrefix [] = []
|
|
longestCommonPrefix (x : xs) = foldr prefix x xs
|
|
where
|
|
prefix l1 l2 = map fst $ takeWhile (uncurry (==)) $ zip l1 l2
|
|
|
|
appendToNonEmpty :: NE.NonEmpty a -> [a] -> NE.NonEmpty a
|
|
appendToNonEmpty (neHead NE.:| neList) list =
|
|
neHead NE.:| (neList <> list)
|