@@ -1,95 +1,151 @@
1+{-# LANGUAGE CPP #-}
12{-# LANGUAGE DeriveTraversable #-}
23{-# LANGUAGE FlexibleContexts #-}
34{-# LANGUAGE FlexibleInstances #-}
5+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
46{-# LANGUAGE LambdaCase #-}
57{-# LANGUAGE MultiParamTypeClasses #-}
68{-# LANGUAGE PatternGuards #-}
9+{-# LANGUAGE PatternSynonyms #-}
710{-# LANGUAGE ScopedTypeVariables #-}
11+{-# LANGUAGE StandaloneDeriving #-}
812{-# LANGUAGE TemplateHaskell #-}
913{-# LANGUAGE TypeApplications #-}
1014{-# LANGUAGE TypeFamilies #-}
15+{-# LANGUAGE ViewPatterns #-}
1116
1217-- | 'Patch'es on 'Map' that can insert, delete, and move values from one key to
1318-- another
14−module Data.Patch.MapWithMove where
19+module Data.Patch.MapWithMove
20+ ( PatchMapWithMove
21+ ( PatchMapWithMove
22+ , unPatchMapWithMove
23+ , ..
24+ )
25+ , patchMapWithMove
26+ , patchMapWithMoveInsertAll
27+ , insertMapKey
28+ , moveMapKey
29+ , swapMapKey
30+ , deleteMapKey
31+ , unsafePatchMapWithMove
32+ , patchMapWithMoveNewElements
33+ , patchMapWithMoveNewElementsMap
34+ , patchThatSortsMapWith
35+ , patchThatChangesAndSortsMapWith
36+ , patchThatChangesMap
1537
38+ -- * Node Info
39+ , NodeInfo
40+ ( NodeInfo
41+ , _nodeInfo_to
42+ , _nodeInfo_from
43+ , ..
44+ )
45+ , bitraverseNodeInfo
46+ , nodeInfoMapFrom
47+ , nodeInfoMapMFrom
48+ , nodeInfoSetTo
49+
50+ -- * From
51+ , From
52+ ( From_Insert
53+ , From_Delete
54+ , From_Move
55+ , ..
56+ )
57+ , bitraverseFrom
58+
59+ -- * To
60+ , To
61+ ) where
62+
63+import Data.Coerce
64+import Data.Kind (Type)
1665import Data.Patch.Class
66+import Data.Patch.MapWithPatchingMove (PatchMapWithPatchingMove(..), To)
67+import qualified Data.Patch.MapWithPatchingMove as PM -- already a transparent synonym
1768
18−import Control.Arrow
19−import Control.Lens hiding (from, to)
20−import Control.Monad.Trans.State
21−import Data.Foldable
22−import Data.Function
69+import Control.Lens
2370import Data.List
2471import Data.Map (Map)
2572import qualified Data.Map as Map
26−import Data.Maybe
27−import Data.Semigroup (Semigroup (..), (<>))
28−import qualified Data.Set as Set
29−import Data.These (These(..))
30−import Data.Tuple
73+import Data.Proxy
74+#if !MIN_VERSION_base(4,11,0)
75+import Data.Semigroup (Semigroup (..))
76+#endif
77+import Data.Traversable (foldMapDefault)
3178
3279-- | Patch a Map with additions, deletions, and moves. Invariant: If key @k1@
3380-- is coming from @From_Move k2@, then key @k2@ should be going to @Just k1@,
3481-- and vice versa. There should never be any unpaired From/To keys.
35−newtype PatchMapWithMove k v = PatchMapWithMove
36− { -- | Extract the internal representation of the 'PatchMapWithMove'
37− unPatchMapWithMove :: Map k (NodeInfo k v)
82+newtype PatchMapWithMove k (v :: Type) = PatchMapWithMove'
83+ { -- | Extract the underlying 'PatchMapWithPatchingMove k (Proxy v)'
84+ unPatchMapWithMove' :: PatchMapWithPatchingMove k (Proxy v)
3885 }
3986 deriving ( Show, Read, Eq, Ord
40− , Functor, Foldable, Traversable
87+-- Haddock cannot handle documentation here before GHC 8.6
88+ ,
89+#if __GLASGOW_HASKELL__ >= 806
90+ -- | Compose patches having the same effect as applying the
91+ -- patches in turn: @'applyAlways' (p <> q) == 'applyAlways' p .
92+ -- 'applyAlways' q@
93+#endif
94+ Semigroup
95+ , Monoid
4196 )
4297
43−-- | Holds the information about each key: where its new value should come from,
44−-- and where its old value should go to
45−data NodeInfo k v = NodeInfo
46− { _nodeInfo_from :: !(From k v)
47− -- ^ Where do we get the new value for this key?
48− , _nodeInfo_to :: !(To k)
49− -- ^ If the old value is being kept (i.e. moved rather than deleted or
50− -- replaced), where is it going?
51− }
52− deriving (Show, Read, Eq, Ord, Functor, Foldable, Traversable)
98+pattern Coerce :: Coercible a b => a -> b
99+pattern Coerce x <- (coerce -> x)
100+ where Coerce x = coerce x
53101
54−-- | Describe how a key's new value should be produced
55−data From k v
56− = From_Insert v -- ^ Insert the given value here
57− | From_Delete -- ^ Delete the existing value, if any, from here
58− | From_Move !k -- ^ Move the value here from the given key
59− deriving (Show, Read, Eq, Ord, Functor, Foldable, Traversable)
102+{-# COMPLETE PatchMapWithMove #-}
103+pattern PatchMapWithMove :: Map k (NodeInfo k v) -> PatchMapWithMove k v
104+-- | Extract the representation of the 'PatchMapWithMove' as a map of
105+-- 'NodeInfo'.
106+unPatchMapWithMove :: PatchMapWithMove k v -> Map k (NodeInfo k v)
107+pattern PatchMapWithMove { unPatchMapWithMove } = PatchMapWithMove' (PatchMapWithPatchingMove (Coerce unPatchMapWithMove))
60108
61−-- | Describe where a key's old value will go. If this is 'Just', that means
62−-- the key's old value will be moved to the given other key; if it is 'Nothing',
63−-- that means it will be deleted.
64−type To = Maybe
109+_PatchMapWithMove
110+ :: Iso
111+ (PatchMapWithMove k0 v0)
112+ (PatchMapWithMove k1 v1)
113+ (Map k0 (NodeInfo k0 v0))
114+ (Map k1 (NodeInfo k1 v1))
115+_PatchMapWithMove = iso unPatchMapWithMove PatchMapWithMove
65116
66−makeWrapped ''PatchMapWithMove
117+instance Functor (PatchMapWithMove k) where
118+ fmap f = runIdentity . traverse (Identity . f)
119+
120+instance Foldable (PatchMapWithMove k) where
121+ foldMap = foldMapDefault
122+
123+instance Traversable (PatchMapWithMove k) where
124+ traverse =
125+ _PatchMapWithMove .
126+ traverse .
127+ traverse
67128
68129instance FunctorWithIndex k (PatchMapWithMove k)
69130instance FoldableWithIndex k (PatchMapWithMove k)
70131instance TraversableWithIndex k (PatchMapWithMove k) where
71− itraverse f (PatchMapWithMove x) = PatchMapWithMove <$> itraverse (traverse . f) x
132+ itraverse = itraversed . Indexed
133+ itraversed =
134+ _PatchMapWithMove .>
135+ itraversed <.
136+ traverse
72137
73138-- | Create a 'PatchMapWithMove', validating it
74139patchMapWithMove :: Ord k => Map k (NodeInfo k v) -> Maybe (PatchMapWithMove k v)
75−patchMapWithMove m = if valid then Just $ PatchMapWithMove m else Nothing
76− where valid = forwardLinks == backwardLinks
77− forwardLinks = Map.mapMaybe _nodeInfo_to m
78− backwardLinks = Map.fromList $ catMaybes $ flip fmap (Map.toList m) $ \(to, v) ->
79− case _nodeInfo_from v of
80− From_Move from -> Just (from, to)
81− _ -> Nothing
140+patchMapWithMove = fmap PatchMapWithMove' . PM.patchMapWithPatchingMove . coerce
82141
83142-- | Create a 'PatchMapWithMove' that inserts everything in the given 'Map'
84143patchMapWithMoveInsertAll :: Map k v -> PatchMapWithMove k v
85−patchMapWithMoveInsertAll m = PatchMapWithMove $ flip fmap m $ \v -> NodeInfo
86− { _nodeInfo_from = From_Insert v
87− , _nodeInfo_to = Nothing
88− }
144+patchMapWithMoveInsertAll = PatchMapWithMove' . PM.patchMapWithPatchingMoveInsertAll
89145
90146-- | Make a @'PatchMapWithMove' k v@ which has the effect of inserting or updating a value @v@ to the given key @k@, like 'Map.insert'.
91147insertMapKey :: k -> v -> PatchMapWithMove k v
92−insertMapKey k v = PatchMapWithMove . Map.singleton k $ NodeInfo (From_Insert v) Nothing
148+insertMapKey k v = PatchMapWithMove' $ PM.insertMapKey k v
93149
94150-- |Make a @'PatchMapWithMove' k v@ which has the effect of moving the value from the first key @k@ to the second key @k@, equivalent to:
95151--
@@ -97,84 +153,53 @@ insertMapKey k v = PatchMapWithMove . Map.singleton k $ NodeInfo (From_Insert v)
97153-- 'Map.delete' src (maybe map ('Map.insert' dst) (Map.lookup src map))
98154-- @
99155moveMapKey :: Ord k => k -> k -> PatchMapWithMove k v
100−moveMapKey src dst
101− | src == dst = mempty
102− | otherwise =
103− PatchMapWithMove $ Map.fromList
104− [ (dst, NodeInfo (From_Move src) Nothing)
105− , (src, NodeInfo From_Delete (Just dst))
106− ]
156+moveMapKey src dst = PatchMapWithMove' $ PM.moveMapKey src dst
107157
108158-- |Make a @'PatchMapWithMove' k v@ which has the effect of swapping two keys in the mapping, equivalent to:
109159--
110160-- @
111161-- let aMay = Map.lookup a map
112162-- bMay = Map.lookup b map
113−-- in maybe id (Map.insert a) (bMay `mplus` aMay)
114−-- . maybe id (Map.insert b) (aMay `mplus` bMay)
163+-- in maybe id (Map.insert a) (bMay <> aMay)
164+-- . maybe id (Map.insert b) (aMay <> bMay)
115165-- . Map.delete a . Map.delete b $ map
116166-- @
117167swapMapKey :: Ord k => k -> k -> PatchMapWithMove k v
118−swapMapKey src dst
119− | src == dst = mempty
120− | otherwise =
121− PatchMapWithMove $ Map.fromList
122− [ (dst, NodeInfo (From_Move src) (Just src))
123− , (src, NodeInfo (From_Move dst) (Just dst))
124− ]
168+swapMapKey src dst = PatchMapWithMove' $ PM.swapMapKey src dst
125169
126170-- |Make a @'PatchMapWithMove' k v@ which has the effect of deleting a key in the mapping, equivalent to 'Map.delete'.
127171deleteMapKey :: k -> PatchMapWithMove k v
128−deleteMapKey k = PatchMapWithMove . Map.singleton k $ NodeInfo From_Delete Nothing
172+deleteMapKey = PatchMapWithMove' . PM.deleteMapKey
129173
130174-- | Wrap a @'Map' k (NodeInfo k v)@ representing patch changes into a @'PatchMapWithMove' k v@, without checking any invariants.
131175--
132176-- __Warning:__ when using this function, you must ensure that the invariants of 'PatchMapWithMove' are preserved; they will not be checked.
133177unsafePatchMapWithMove :: Map k (NodeInfo k v) -> PatchMapWithMove k v
134−unsafePatchMapWithMove = PatchMapWithMove
178+unsafePatchMapWithMove = coerce PM.unsafePatchMapWithPatchingMove
135179
136180-- | Apply the insertions, deletions, and moves to a given 'Map'
137181instance Ord k => Patch (PatchMapWithMove k v) where
138182 type PatchTarget (PatchMapWithMove k v) = Map k v
139− apply (PatchMapWithMove p) old = Just $! insertions `Map.union` (old `Map.difference` deletions) --TODO: return Nothing sometimes --Note: the strict application here is critical to ensuring that incremental merges don't hold onto all their prerequisite events forever; can we make this more robust?
140− where insertions = flip Map.mapMaybeWithKey p $ \_ ni -> case _nodeInfo_from ni of
141− From_Insert v -> Just v
142− From_Move k -> Map.lookup k old
143− From_Delete -> Nothing
144− deletions = flip Map.mapMaybeWithKey p $ \_ ni -> case _nodeInfo_from ni of
145− From_Delete -> Just ()
146− _ -> Nothing
183+ apply (PatchMapWithMove' p) = apply p
147184
148185-- | Returns all the new elements that will be added to the 'Map'.
149186patchMapWithMoveNewElements :: PatchMapWithMove k v -> [v]
150−patchMapWithMoveNewElements = Map.elems . patchMapWithMoveNewElementsMap
187+patchMapWithMoveNewElements = PM.patchMapWithPatchingMoveNewElements . unPatchMapWithMove'
151188
152189-- | Return a @'Map' k v@ with all the inserts/updates from the given @'PatchMapWithMove' k v@.
153190patchMapWithMoveNewElementsMap :: PatchMapWithMove k v -> Map k v
154−patchMapWithMoveNewElementsMap (PatchMapWithMove p) = Map.mapMaybe f p
155− where f ni = case _nodeInfo_from ni of
156− From_Insert v -> Just v
157− From_Move _ -> Nothing
158− From_Delete -> Nothing
191+patchMapWithMoveNewElementsMap = PM.patchMapWithPatchingMoveNewElementsMap . unPatchMapWithMove'
159192
160193-- | Create a 'PatchMapWithMove' that, if applied to the given 'Map', will sort
161194-- its values using the given ordering function. The set keys of the 'Map' is
162195-- not changed.
163196patchThatSortsMapWith :: Ord k => (v -> v -> Ordering) -> Map k v -> PatchMapWithMove k v
164−patchThatSortsMapWith cmp m = PatchMapWithMove $ Map.fromList $ catMaybes $ zipWith g unsorted sorted
165− where unsorted = Map.toList m
166− sorted = sortBy (cmp `on` snd) unsorted
167− f (to, _) (from, _) = if to == from then Nothing else
168− Just (from, to)
169− reverseMapping = Map.fromList $ catMaybes $ zipWith f unsorted sorted
170− g (to, _) (from, _) = if to == from then Nothing else
171− let Just movingTo = Map.lookup to reverseMapping
172− in Just (to, NodeInfo (From_Move from) $ Just movingTo)
197+patchThatSortsMapWith cmp = PatchMapWithMove' . PM.patchThatSortsMapWith cmp
173198
174199-- | Create a 'PatchMapWithMove' that, if applied to the first 'Map' provided,
175200-- will produce a 'Map' with the same values as the second 'Map' but with the
176201-- values sorted with the given ordering function.
177−patchThatChangesAndSortsMapWith :: forall k v. (Ord k, Ord v) => (v -> v -> Ordering) -> Map k v -> Map k v -> PatchMapWithMove k v
202+patchThatChangesAndSortsMapWith :: (Ord k, Ord v) => (v -> v -> Ordering) -> Map k v -> Map k v -> PatchMapWithMove k v
178203patchThatChangesAndSortsMapWith cmp oldByIndex newByIndexUnsorted = patchThatChangesMap oldByIndex newByIndex
179204 where newList = Map.toList newByIndexUnsorted
180205 newByIndex = Map.fromList $ zip (fst <$> newList) $ sortBy cmp $ snd <$> newList
@@ -182,102 +207,106 @@ patchThatChangesAndSortsMapWith cmp oldByIndex newByIndexUnsorted = patchThatCha
182207-- | Create a 'PatchMapWithMove' that, if applied to the first 'Map' provided,
183208-- will produce the second 'Map'.
184209patchThatChangesMap :: (Ord k, Ord v) => Map k v -> Map k v -> PatchMapWithMove k v
185−patchThatChangesMap oldByIndex newByIndex = patch
186− where oldByValue = Map.fromListWith Set.union $ swap . first Set.singleton <$> Map.toList oldByIndex
187− (insertsAndMoves, unusedValuesByValue) = flip runState oldByValue $ do
188− let f k v = do
189− remainingValues <- get
190− let putRemainingKeys remainingKeys = put $ if Set.null remainingKeys
191− then Map.delete v remainingValues
192− else Map.insert v remainingKeys remainingValues
193− case Map.lookup v remainingValues of
194− Nothing -> return $ NodeInfo (From_Insert v) $ Just undefined -- There's no existing value we can take
195− Just fromKs ->
196− if k `Set.member` fromKs
197− then do
198− putRemainingKeys $ Set.delete k fromKs
199− return $ NodeInfo (From_Move k) $ Just undefined -- There's an existing value, and it's here, so no patch necessary
200− else do
201− (fromK, remainingKeys) <- return . fromJust $ Set.minView fromKs -- There's an existing value, but it's not here; move it here
202− putRemainingKeys remainingKeys
203− return $ NodeInfo (From_Move fromK) $ Just undefined
204− Map.traverseWithKey f newByIndex
205− unusedOldKeys = fold unusedValuesByValue
206− pointlessMove k = \case
207− From_Move k' | k == k' -> True
208− _ -> False
209− keyWasMoved k = if k `Map.member` oldByIndex && not (k `Set.member` unusedOldKeys)
210− then Just undefined
211− else Nothing
212− patch = unsafePatchMapWithMove $ Map.filterWithKey (\k -> not . pointlessMove k . _nodeInfo_from) $ Map.mergeWithKey (\k a _ -> Just $ nodeInfoSetTo (keyWasMoved k) a) (Map.mapWithKey $ \k -> nodeInfoSetTo $ keyWasMoved k) (Map.mapWithKey $ \k _ -> NodeInfo From_Delete $ keyWasMoved k) insertsAndMoves oldByIndex
210+patchThatChangesMap oldByIndex newByIndex = PatchMapWithMove' $
211+ PM.patchThatChangesMap oldByIndex newByIndex
212+
213+--
214+-- NodeInfo
215+--
216+
217+-- | Holds the information about each key: where its new value should come from,
218+-- and where its old value should go to
219+newtype NodeInfo k (v :: Type) = NodeInfo' { unNodeInfo' :: PM.NodeInfo k (Proxy v) }
220+
221+deriving instance (Show k, Show p) => Show (NodeInfo k p)
222+deriving instance (Read k, Read p) => Read (NodeInfo k p)
223+deriving instance (Eq k, Eq p) => Eq (NodeInfo k p)
224+deriving instance (Ord k, Ord p) => Ord (NodeInfo k p)
225+
226+{-# COMPLETE NodeInfo #-}
227+pattern NodeInfo :: To k -> From k v -> NodeInfo k v
228+_nodeInfo_to :: NodeInfo k v -> To k
229+_nodeInfo_from :: NodeInfo k v -> From k v
230+pattern NodeInfo { _nodeInfo_to, _nodeInfo_from } = NodeInfo'
231+ PM.NodeInfo
232+ { PM._nodeInfo_to = _nodeInfo_to
233+ , PM._nodeInfo_from = Coerce _nodeInfo_from
234+ }
235+
236+_NodeInfo
237+ :: Iso
238+ (NodeInfo k0 v0)
239+ (NodeInfo k1 v1)
240+ (PM.NodeInfo k0 (Proxy v0))
241+ (PM.NodeInfo k1 (Proxy v1))
242+_NodeInfo = iso unNodeInfo' NodeInfo'
243+
244+instance Functor (NodeInfo k) where
245+ fmap f = runIdentity . traverse (Identity . f)
246+
247+instance Foldable (NodeInfo k) where
248+ foldMap = foldMapDefault
249+
250+instance Traversable (NodeInfo k) where
251+ traverse = bitraverseNodeInfo pure
252+
253+bitraverseNodeInfo
254+ :: Applicative f
255+ => (k0 -> f k1)
256+ -> (v0 -> f v1)
257+ -> NodeInfo k0 v0 -> f (NodeInfo k1 v1)
258+bitraverseNodeInfo fk fv = fmap NodeInfo'
259+ . PM.bitraverseNodeInfo fk (\ ~Proxy -> pure Proxy) fv
260+ . coerce
213261
214262-- | Change the 'From' value of a 'NodeInfo'
215263nodeInfoMapFrom :: (From k v -> From k v) -> NodeInfo k v -> NodeInfo k v
216−nodeInfoMapFrom f ni = ni { _nodeInfo_from = f $ _nodeInfo_from ni }
264+nodeInfoMapFrom f = coerce $ PM.nodeInfoMapFrom (unFrom' . f . From')
217265
218266-- | Change the 'From' value of a 'NodeInfo', using a 'Functor' (or
219267-- 'Applicative', 'Monad', etc.) action to get the new value
220−nodeInfoMapMFrom :: Functor f => (From k v -> f (From k v)) -> NodeInfo k v -> f (NodeInfo k v)
221−nodeInfoMapMFrom f ni = fmap (\result -> ni { _nodeInfo_from = result }) $ f $ _nodeInfo_from ni
268+nodeInfoMapMFrom
269+ :: Functor f
270+ => (From k v -> f (From k v))
271+ -> NodeInfo k v -> f (NodeInfo k v)
272+nodeInfoMapMFrom f = fmap NodeInfo'
273+ . PM.nodeInfoMapMFrom (fmap unFrom' . f . From')
274+ . coerce
222275
223276-- | Set the 'To' field of a 'NodeInfo'
224277nodeInfoSetTo :: To k -> NodeInfo k v -> NodeInfo k v
225−nodeInfoSetTo to ni = ni { _nodeInfo_to = to }
226−
227−-- |Helper data structure used for composing patches using the monoid instance.
228−data Fixup k v
229− = Fixup_Delete
230− | Fixup_Update (These (From k v) (To k))
231−
232−-- |Compose patches having the same effect as applying the patches in turn: @'applyAlways' (p <> q) == 'applyAlways' p . 'applyAlways' q@
233−instance Ord k => Semigroup (PatchMapWithMove k v) where
234− PatchMapWithMove ma <> PatchMapWithMove mb = PatchMapWithMove m
235− where
236− connections = Map.toList $ Map.intersectionWithKey (\_ a b -> (_nodeInfo_to a, _nodeInfo_from b)) ma mb
237− h :: (k, (Maybe k, From k v)) -> [(k, Fixup k v)]
238− h (_, (mToAfter, editBefore)) = case (mToAfter, editBefore) of
239− (Just toAfter, From_Move fromBefore)
240− | fromBefore == toAfter
241− -> [(toAfter, Fixup_Delete)]
242− | otherwise
243− -> [ (toAfter, Fixup_Update (This editBefore))
244− , (fromBefore, Fixup_Update (That mToAfter))
245− ]
246− (Nothing, From_Move fromBefore) -> [(fromBefore, Fixup_Update (That mToAfter))] -- The item is destroyed in the second patch, so indicate that it is destroyed in the source map
247− (Just toAfter, _) -> [(toAfter, Fixup_Update (This editBefore))]
248− (Nothing, _) -> []
249− mergeFixups _ Fixup_Delete Fixup_Delete = Fixup_Delete
250− mergeFixups _ (Fixup_Update a) (Fixup_Update b)
251− | This x <- a, That y <- b
252− = Fixup_Update $ These x y
253− | That y <- a, This x <- b
254− = Fixup_Update $ These x y
255− mergeFixups _ _ _ = error "PatchMapWithMove: incompatible fixups"
256− fixups = Map.fromListWithKey mergeFixups $ concatMap h connections
257− combineNodeInfos _ nia nib = NodeInfo
258− { _nodeInfo_from = _nodeInfo_from nia
259− , _nodeInfo_to = _nodeInfo_to nib
260− }
261− applyFixup _ ni = \case
262− Fixup_Delete -> Nothing
263− Fixup_Update u -> Just $ NodeInfo
264− { _nodeInfo_from = fromMaybe (_nodeInfo_from ni) $ getHere u
265− , _nodeInfo_to = fromMaybe (_nodeInfo_to ni) $ getThere u
266− }
267− m = Map.differenceWithKey applyFixup (Map.unionWithKey combineNodeInfos ma mb) fixups
268− getHere :: These a b -> Maybe a
269− getHere = \case
270− This a -> Just a
271− These a _ -> Just a
272− That _ -> Nothing
273− getThere :: These a b -> Maybe b
274− getThere = \case
275− This _ -> Nothing
276− These _ b -> Just b
277− That b -> Just b
278−
279−--TODO: Figure out how to implement this in terms of PatchDMapWithMove rather than duplicating it here
280−-- |Compose patches having the same effect as applying the patches in turn: @'applyAlways' (p <> q) == 'applyAlways' p . 'applyAlways' q@
281−instance Ord k => Monoid (PatchMapWithMove k v) where
282− mempty = PatchMapWithMove mempty
283− mappend = (<>)
278+nodeInfoSetTo = coerce . PM.nodeInfoSetTo
279+
280+--
281+-- From
282+--
283+
284+-- | Describe how a key's new value should be produced
285+newtype From k (v :: Type) = From' { unFrom' :: PM.From k (Proxy v) }
286+
287+{-# COMPLETE From_Insert, From_Delete, From_Move #-}
288+
289+-- | Insert the given value here
290+pattern From_Insert :: v -> From k v
291+pattern From_Insert v = From' (PM.From_Insert v)
292+
293+-- | Delete the existing value, if any, from here
294+pattern From_Delete :: From k v
295+pattern From_Delete = From' PM.From_Delete
296+
297+-- | Move the value here from the given key
298+pattern From_Move :: k -> From k v
299+pattern From_Move k = From' (PM.From_Move k Proxy)
300+
301+bitraverseFrom
302+ :: Applicative f
303+ => (k0 -> f k1)
304+ -> (v0 -> f v1)
305+ -> From k0 v0 -> f (From k1 v1)
306+bitraverseFrom fk fv = fmap From'
307+ . PM.bitraverseFrom fk (\ ~Proxy -> pure Proxy) fv
308+ . coerce
309+
310+makeWrapped ''PatchMapWithMove
311+makeWrapped ''NodeInfo
312+makeWrapped ''From