on aa7311b help sign in
11 files changed+464−69
since splitsnapshots
unifiedsplit
ChangeLog.md+4 patch.cabal+2 src/Data/Patch.hs+7−5 src/Data/Patch/Class.hs+84−6 src/Data/Patch/DMap.hs+3−1 src/Data/Patch/DMapWithMove.hs+185−52 src/Data/Patch/DMapWithReset.hs+120 src/Data/Patch/IntMap.hs+3−1 src/Data/Patch/Map.hs+3−1 src/Data/Patch/MapWithMove.hs+8−3 src/Data/Patch/Patchable.hs+45
ChangeLog.md+4
@@ -4,6 +4,10 @@
44
55* `PatchMapWithMove` supports moves with a patch.
66
7+* Add `PatchDMapWithReset`
8+
9+* Add `Patchable`
10+
711## 0.0.1.0
812
913* Support older GHCs with `split-these` flag.
patch.cabal+2
@@ -44,9 +44,11 @@ library
4444 , Data.Patch.Class
4545 , Data.Patch.DMap
4646 , Data.Patch.DMapWithMove
47+ , Data.Patch.DMapWithReset
4748 , Data.Patch.IntMap
4849 , Data.Patch.Map
4950 , Data.Patch.MapWithMove
51+ , Data.Patch.Patchable
5052
5153 ghc-options: -Wall -fwarn-redundant-constraints -fwarn-tabs
5254
src/Data/Patch.hs+7−5
@@ -51,8 +51,10 @@ class Semigroup q => Additive q where
5151-- | The elements of an 'Additive' 'Semigroup' can be considered as patches of their own type.
5252newtype AdditivePatch p = AdditivePatch { unAdditivePatch :: p }
5353
54−instance Additive p => Patch (AdditivePatch p) where
54+instance Additive p => PatchHet (AdditivePatch p) where
55+ type PatchSource (AdditivePatch p) = p
5556 type PatchTarget (AdditivePatch p) = p
57+instance Additive p => Patch (AdditivePatch p) where
5658 apply (AdditivePatch p) q = Just $ p <> q
5759
5860instance (Ord k, Group q) => Group (MonoidalMap k q) where
@@ -62,8 +64,8 @@ instance (Ord k, Additive q) => Additive (MonoidalMap k q)
6264
6365-- | Trivial group.
6466instance Group () where
65− negateG _ = ()
66− _ ~~ _ = ()
67+ negateG ~() = ()
68+ ~() ~~ ~() = ()
6769instance Additive ()
6870
6971-- | Product group. A Pair of groups gives rise to a group
@@ -88,8 +90,8 @@ instance (Additive (f a), Additive (g a)) => Additive ((f :*: g) a)
8890
8991-- | Trivial group, Functor style
9092instance Group (Proxy x) where
91− negateG _ = Proxy
92− _ ~~ _ = Proxy
93+ negateG ~Proxy = Proxy
94+ ~Proxy ~~ ~Proxy = Proxy
9395instance Additive (Proxy x)
9496
9597-- | Const lifts groups into a functor.
src/Data/Patch/Class.hs+84−6
@@ -1,4 +1,10 @@
1+{-# LANGUAGE DefaultSignatures #-}
2+{-# LANGUAGE DeriveTraversable #-}
3+{-# LANGUAGE FlexibleInstances #-}
4+{-# LANGUAGE PolyKinds #-}
5+{-# LANGUAGE QuantifiedConstraints #-}
16{-# LANGUAGE TypeFamilies #-}
7+{-# LANGUAGE TypeOperators #-}
28-- | The interface for types which represent changes made to other types
39module Data.Patch.Class where
410
@@ -6,13 +12,39 @@ import Data.Functor.Identity
612import Data.Maybe
713import Data.Semigroup (Semigroup(..))
814import Data.Proxy
15+import Data.Type.Equality ((:~:) (..))
16+
17+class PatchHet p where
18+ type PatchSource p :: *
19+ type PatchTarget p :: *
20+ -- | Apply the patch @p a@ to the value @a@. If no change is needed, return
21+ -- 'Nothing'.
22+ applyHet
23+ :: p
24+ -> PatchSource p
25+ -> Either (PatchSource p :~: PatchTarget p) (PatchTarget p)
26+ default applyHet
27+ :: Patch p
28+ => p
29+ -> PatchSource p
30+ -> Either (PatchSource p :~: PatchTarget p) (PatchTarget p)
31+ applyHet p a = case apply p a of
32+ Nothing -> Left Refl
33+ Just a' -> Right a'
34+
35+-- | Apply a 'PatchHet'; if it does nothing, return the original value
36+applyAlwaysHet :: PatchHet p => p -> PatchSource p -> PatchTarget p
37+applyAlwaysHet p t = case applyHet p t of
38+ Left Refl -> t
39+ Right t' -> t'
940
1041-- | A 'Patch' type represents a kind of change made to a datastructure.
1142--
1243-- If an instance of 'Patch' is also an instance of 'Semigroup', it should obey
1344-- the law that @applyAlways (f <> g) == applyAlways f . applyAlways g@.
14−class Patch p where
15− type PatchTarget p :: *
45+class ( PatchHet p
46+ , PatchSource p ~ PatchTarget p
47+ ) => Patch p where
1648 -- | Apply the patch @p a@ to the value @a@. If no change is needed, return
1749 -- 'Nothing'.
1850 apply :: p -> PatchTarget p -> Maybe (PatchTarget p)
@@ -22,19 +54,65 @@ applyAlways :: Patch p => p -> PatchTarget p -> PatchTarget p
2254applyAlways p t = fromMaybe t $ apply p t
2355
2456-- | 'Identity' can be used as a 'Patch' that always fully replaces the value
25−instance Patch (Identity a) where
57+instance PatchHet (Identity a) where
58+ type PatchSource (Identity a) = a
2659 type PatchTarget (Identity a) = a
60+instance Patch (Identity a) where
2761 apply (Identity a) _ = Just a
2862
29−-- | 'Identity' can be used as a 'Patch' that always fully replaces the value
30−instance Patch (Proxy a) where
63+-- | 'Proxy' can be used as a 'Patch' that always fully replaces the value
64+instance PatchHet (Proxy (a :: *)) where
65+ type PatchSource (Proxy a) = a
3166 type PatchTarget (Proxy a) = a
67+instance Patch (Proxy (a :: *)) where
3268 apply ~Proxy _ = Nothing
3369
3470-- | Like '(.)', but composes functions that return patches rather than
3571-- functions that return new values. The Semigroup instance for patches must
3672-- apply patches right-to-left, like '(.)'.
37−composePatchFunctions :: (Patch p, Semigroup p) => (PatchTarget p -> p) -> (PatchTarget p -> p) -> PatchTarget p -> p
73+composePatchFunctions
74+ :: (Patch p, Semigroup p)
75+ => (PatchTarget p -> p)
76+ -> (PatchTarget p -> p)
77+ -> PatchTarget p -> p
3878composePatchFunctions g f a =
3979 let fp = f a
4080 in g (applyAlways fp a) <> fp
81+
82+class (forall x y
83+ . ( PatchHet (p x y)
84+ , PatchSource1 p x ~ PatchSource (p x y)
85+ , PatchTarget1 p y ~ PatchTarget (p x y)
86+ )
87+ ) => PatchHet2 (p :: k -> k -> *) where
88+ type PatchSource1 p :: k -> *
89+ type PatchTarget1 p :: k -> *
90+
91+class ( PatchHet2 p
92+ , PatchSource1 p ~ PatchTarget1 p
93+ ) => Patch2 p
94+instance ( PatchHet2 p
95+ , PatchSource1 p ~ PatchTarget1 p
96+ ) => Patch2 p
97+
98+newtype Replace2 (t :: k -> *) (a :: k) (b :: k) = Replace2 (t b)
99+ deriving ( Show, Read, Eq, Ord
100+ , Functor, Foldable, Traversable
101+ )
102+
103+data Proxy2 t a b = Proxy2
104+ deriving ( Show, Read, Eq, Ord
105+ , Functor, Foldable, Traversable
106+ )
107+
108+-- | 'Replace2' can be used as a 'Patch' that always fully replaces the value
109+instance PatchHet (Replace2 (t :: k -> *) (a :: k) (b :: k)) where
110+ type PatchSource (Replace2 t a b) = t a
111+ type PatchTarget (Replace2 t a b) = t b
112+ applyHet (Replace2 val) _ = Right val
113+
114+-- | 'Proxy2' can be used as a 'Patch' that always fully replaces the value
115+instance PatchHet (Proxy2 (t :: k -> *) (a :: k) (a :: k)) where
116+ type PatchSource (Proxy2 t a a) = t a
117+ type PatchTarget (Proxy2 t a a) = t a
118+ applyHet ~Proxy2 _ = Left Refl
src/Data/Patch/DMap.hs+3−1
@@ -31,8 +31,10 @@ deriving instance GCompare k => Semigroup (PatchDMap k v)
3131deriving instance GCompare k => Monoid (PatchDMap k v)
3232
3333-- | Apply the insertions or deletions to a given 'DMap'.
34−instance GCompare k => Patch (PatchDMap k v) where
34+instance GCompare k => PatchHet (PatchDMap k v) where
35+ type PatchSource (PatchDMap k v) = DMap k v
3536 type PatchTarget (PatchDMap k v) = DMap k v
37+instance GCompare k => Patch (PatchDMap k v) where
3638 apply (PatchDMap diff) old = Just $! insertions `DMap.union` (old `DMap.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?
3739 where insertions = DMap.mapMaybeWithKey (const $ getComposeMaybe) diff
3840 deletions = DMap.mapMaybeWithKey (const $ nothingToJust . getComposeMaybe) diff
src/Data/Patch/DMapWithMove.hs+185−52
@@ -1,4 +1,5 @@
11{-# LANGUAGE CPP #-}
2+{-# LANGUAGE ConstraintKinds #-}
23{-# LANGUAGE FlexibleContexts #-}
34{-# LANGUAGE FlexibleInstances #-}
45{-# LANGUAGE GADTs #-}
@@ -8,8 +9,11 @@
89{-# LANGUAGE PolyKinds #-}
910{-# LANGUAGE Rank2Types #-}
1011{-# LANGUAGE ScopedTypeVariables #-}
12+{-# LANGUAGE StandaloneDeriving #-}
13+{-# LANGUAGE TypeApplications #-}
1114{-# LANGUAGE TypeFamilies #-}
1215{-# LANGUAGE UndecidableInstances #-}
16+{-# LANGUAGE UndecidableSuperClasses #-}
1317
1418-- |Module containing @'PatchDMapWithMove' k v@ and associated functions, which represents a 'Patch' to a @'DMap' k v@ which can insert, update, delete, and
1519-- move values between keys.
@@ -20,19 +24,34 @@ import Data.Patch.MapWithMove (PatchMapWithMove (..))
2024import qualified Data.Patch.MapWithMove as MapWithMove
2125
2226import Data.Constraint.Extras
27+import Data.Constraint.Compose
2328import Data.Dependent.Map (DMap, DSum (..), GCompare (..))
2429import qualified Data.Dependent.Map as DMap
2530import Data.Functor.Constant
2631import Data.Functor.Misc
2732import Data.Functor.Product
28−import Data.GADT.Compare (GEq (..))
29−import Data.GADT.Show (GShow, gshow)
33+import Data.GADT.Compare (GEq (..), GCompare)
34+import Data.GADT.Show (GRead, GShow, gshow)
3035import qualified Data.Map as Map
3136import Data.Maybe
37+import Data.Monoid.DecidablyEmpty
3238import Data.Semigroup (Semigroup (..), (<>))
3339import Data.Some (Some(Some))
3440import Data.Proxy
3541import Data.These
42+import Data.Type.Equality ((:~:) (..))
43+import Data.Kind (Constraint)
44+
45+
46+-- | Composition for constraints.
47+class p (f a a) => DupC (p :: k2 -> Constraint) (f :: k1 -> k1 -> k2) (a :: k1)
48+instance p (f a a) => DupC p f a
49+
50+type ConstraintsForZip f (c :: k -> Constraint) (g :: k' -> k' -> k) =
51+ ConstraintsFor f (DupC c g)
52+
53+type HasZip (c :: k -> Constraint) f (g :: k' -> k' -> k) =
54+ (ArgDict (DupC c g) f, ConstraintsForZip f c g)
3655
3756-- | Like 'PatchMapWithMove', but for 'DMap'. Each key carries a 'NodeInfo' which describes how it will be changed by the patch and connects move sources and
3857-- destinations.
@@ -43,47 +62,119 @@ import Data.These
4362-- * A move should always be represented with both the destination key (as a 'From_Move') and the source key (as a @'ComposeMaybe' ('Just' destination)@)
4463newtype PatchDMapWithMove k v = PatchDMapWithMove (DMap k (NodeInfo k v))
4564
65+deriving instance ( GShow k
66+ , HasZip Show k p
67+ , Has' Show k (PatchTarget1 p)
68+ ) => Show (PatchDMapWithMove k p)
69+deriving instance ( GRead k
70+ , HasZip Read k p
71+ , Has' Read k (PatchTarget1 p)
72+ ) => Read (PatchDMapWithMove k p)
73+deriving instance ( GEq k
74+ , HasZip Eq k p
75+ , Has' Eq k (PatchTarget1 p)
76+ ) => Eq (PatchDMapWithMove k p)
77+deriving instance ( GCompare k
78+ , HasZip Ord k p
79+ , Has' Ord k (PatchTarget1 p)
80+ ) => Ord (PatchDMapWithMove k p)
81+
4682-- |Structure which represents what changes apply to a particular key. @_nodeInfo_from@ specifies what happens to this key, and in particular what other key
4783-- the current key is moving from, while @_nodeInfo_to@ specifies what key the current key is moving to if involved in a move.
48−data NodeInfo k v a = NodeInfo
49− { _nodeInfo_from :: !(From k v a)
84+data NodeInfo k p a = NodeInfo
85+ { _nodeInfo_from :: !(From k p a)
5086 -- ^Change applying to the current key, be it an insert, move, or delete.
5187 , _nodeInfo_to :: !(To k a)
5288 -- ^Where this key is moving to, if involved in a move. Should only be @ComposeMaybe (Just k)@ when there is a corresponding 'From_Move'.
5389 }
54− deriving (Show)
90+
91+deriving instance ( Show (k a)
92+ , Show (p a a)
93+ , Show (PatchTarget1 p a)
94+ ) => Show (NodeInfo k p a)
95+deriving instance ( Read (k a)
96+ , Read (p a a)
97+ , Read (PatchTarget1 p a)
98+ ) => Read (NodeInfo k p a)
99+deriving instance ( Eq (k a)
100+ , Eq (p a a)
101+ , Eq (PatchTarget1 p a)
102+ ) => Eq (NodeInfo k p a)
103+deriving instance ( Ord (k a)
104+ , Ord (p a a)
105+ , Ord (PatchTarget1 p a)
106+ ) => Ord (NodeInfo k p a)
55107
56108-- |Structure describing a particular change to a key, be it inserting a new key (@From_Insert@), updating an existing key (@From_Insert@ again), deleting a
57109-- key (@From_Delete@), or moving a key (@From_Move@).
58−data From (k :: a -> *) (v :: a -> *) :: a -> * where
59− -- |Insert a new or update an existing key with the given value @v a@
60− From_Insert :: v a -> From k v a
110+data From (k :: a -> *) (p :: a -> a -> *) :: a -> * where
111+ -- |Insert a new or update an existing key with the given value @PatchTarget1 p a@
112+ From_Insert :: PatchTarget1 p a -> From k p a
61113 -- |Delete the existing key
62− From_Delete :: From k v a
114+ From_Delete :: From k p a
63115 -- |Move the value from the given key @k a@ to this key. The source key should also have an entry in the patch giving the current key as @_nodeInfo_to@,
64116 -- usually but not necessarily with @From_Delete@.
65− From_Move :: !(k a) -> From k v a
66− deriving (Show, Read, Eq, Ord)
117+ From_Move :: !(k a0) -> p a0 a1 -> From k p a1
118+
119+deriving instance ( Show (k a)
120+ , Show (p a a)
121+ , Show (PatchTarget1 p a)
122+ ) => Show (From k p a)
123+deriving instance ( Read (k a)
124+ , Read (p a a)
125+ , Read (PatchTarget1 p a)
126+ ) => Read (From k p a)
127+
128+instance ( GEq k
129+ , HasZip Eq k p
130+ , Eq (PatchTarget1 p a)
131+ ) => Eq (From k p a) where
132+ From_Insert p0 == From_Insert p1 = p0 == p1
133+ From_Delete == From_Delete = True
134+ From_Move k0 p0 == From_Move k1 p1 = case geq k0 k1 of
135+ Nothing -> False
136+ Just Refl -> has @(DupC Eq p) k0 $ p0 == p1
137+
138+instance ( GCompare k
139+ , HasZip Ord k p
140+ , Ord (PatchTarget1 p a)
141+ ) => Ord (From k p a) where
142+ From_Insert p0 `compare` From_Insert p1 = p0 `compare` p1
143+ From_Delete `compare` From_Delete = EQ
144+ From_Move k0 p0 `compare` From_Move k1 p1 = case gcompare k0 k1 of
145+ DMap.GGT -> GT
146+ DMap.GEQ -> has @(DupC Ord p) k0 $ p0 `compare` p1
147+ DMap.GLT -> LT
67148
68149-- |Type alias for the "to" part of a 'NodeInfo'. @'ComposeMaybe' ('Just' k)@ means the key is moving to another key, @ComposeMaybe Nothing@ for any other
69150-- operation.
70151type To = ComposeMaybe
71152
72153-- |Test whether a 'PatchDMapWithMove' satisfies its invariants.
73−validPatchDMapWithMove :: forall k v. (GCompare k, GShow k) => DMap k (NodeInfo k v) -> Bool
154+validPatchDMapWithMove
155+ :: forall k v
156+ . (GCompare k, GShow k)
157+ => DMap k (NodeInfo k v)
158+ -> Bool
74159validPatchDMapWithMove = not . null . validationErrorsForPatchDMapWithMove
75160
76161-- |Enumerate what reasons a 'PatchDMapWithMove' doesn't satisfy its invariants, returning @[]@ if it's valid.
77−validationErrorsForPatchDMapWithMove :: forall k v. (GCompare k, GShow k) => DMap k (NodeInfo k v) -> [String]
162+validationErrorsForPatchDMapWithMove
163+ :: forall k v
164+ . (GCompare k, GShow k)
165+ => DMap k (NodeInfo k v)
166+ -> [String]
78167validationErrorsForPatchDMapWithMove m =
79168 noSelfMoves <> movesBalanced
80169 where
81170 noSelfMoves = mapMaybe selfMove . DMap.toAscList $ m
82− selfMove (dst :=> NodeInfo (From_Move src) _) | Just _ <- dst `geq` src = Just $ "self move of key " <> gshow src <> " at destination side"
83− selfMove (src :=> NodeInfo _ (ComposeMaybe (Just dst))) | Just _ <- src `geq` dst = Just $ "self move of key " <> gshow dst <> " at source side"
171+ selfMove (dst :=> NodeInfo (From_Move src _) _)
172+ | Just _ <- dst `geq` src = Just $ "self move of key " <> gshow src <> " at destination side"
173+ selfMove (src :=> NodeInfo _ (ComposeMaybe (Just dst)))
174+ | Just _ <- src `geq` dst = Just $ "self move of key " <> gshow dst <> " at source side"
84175 selfMove _ = Nothing
85176 movesBalanced = mapMaybe unbalancedMove . DMap.toAscList $ m
86− unbalancedMove (dst :=> NodeInfo (From_Move src) _) =
177+ unbalancedMove (dst :=> NodeInfo (From_Move src _) _) =
87178 case DMap.lookup src m of
88179 Nothing -> Just $ "unbalanced move at destination key " <> gshow dst <> " supposedly from " <> gshow src <> " but source key is not in the patch"
89180 Just (NodeInfo _ (ComposeMaybe (Just dst'))) ->
@@ -95,7 +186,7 @@ validationErrorsForPatchDMapWithMove m =
95186 unbalancedMove (src :=> NodeInfo _ (ComposeMaybe (Just dst))) =
96187 case DMap.lookup dst m of
97188 Nothing -> Just $ " unbalanced move at source key " <> gshow src <> " supposedly going to " <> gshow dst <> " but destination key is not in the patch"
98− Just (NodeInfo (From_Move src') _) ->
189+ Just (NodeInfo (From_Move src' _) _) ->
99190 if isNothing (src' `geq` src)
100191 then Just $ "unbalanced move at source key " <> gshow src <> " to " <> gshow dst <> " is coming from " <> gshow src' <> " instead"
101192 else Nothing
@@ -104,10 +195,6 @@ validationErrorsForPatchDMapWithMove m =
104195 Just $ "unbalanced move at source key " <> gshow src <> " supposedly going to " <> gshow dst <> " but destination key is not moving"
105196 unbalancedMove _ = Nothing
106197
107−-- |Test whether two @'PatchDMapWithMove' k v@ contain the same patch operations.
108−instance (GEq k, Has' Eq k (NodeInfo k v)) => Eq (PatchDMapWithMove k v) where
109− PatchDMapWithMove a == PatchDMapWithMove b = a == b
110−
111198-- |Higher kinded 2-tuple, identical to @Data.Functor.Product@ from base ≥ 4.9
112199data Pair1 f g a = Pair1 (f a) (g a)
113200
@@ -117,20 +204,25 @@ data Fixup k v a
117204 | Fixup_Update (These (From k v a) (To k a))
118205
119206-- |Compose patches having the same effect as applying the patches in turn: @'applyAlways' (p <> q) == 'applyAlways' p . 'applyAlways' q@
120−instance GCompare k => Semigroup (PatchDMapWithMove k v) where
207+instance ( GCompare k
208+ -- , DecidablyEmpty p
209+ , PatchHet2 p
210+ ) => Semigroup (PatchDMapWithMove k p) where
121211 PatchDMapWithMove ma <> PatchDMapWithMove mb = PatchDMapWithMove m
122212 where
123213 connections = DMap.toList $ DMap.intersectionWithKey (\_ a b -> Pair1 (_nodeInfo_to a) (_nodeInfo_from b)) ma mb
124214 h :: DSum k (Pair1 (ComposeMaybe k) (From k v)) -> [DSum k (Fixup k v)]
125215 h (_ :=> Pair1 (ComposeMaybe mToAfter) editBefore) = case (mToAfter, editBefore) of
126− (Just toAfter, From_Move fromBefore)
127− | isJust $ fromBefore `geq` toAfter
216+ (Just toAfter, From_Move fromBefore p)
217+ | case fromBefore `geq` toAfter of
218+ Nothing -> False
219+ Just Refl -> isNull p
128220 -> [toAfter :=> Fixup_Delete]
129221 | otherwise
130222 -> [ toAfter :=> Fixup_Update (This editBefore)
131223 , fromBefore :=> Fixup_Update (That (ComposeMaybe mToAfter))
132224 ]
133− (Nothing, From_Move fromBefore) -> [fromBefore :=> Fixup_Update (That (ComposeMaybe mToAfter))] -- The item is destroyed in the second patch, so indicate that it is destroyed in the source map
225+ (Nothing, From_Move fromBefore _) -> [fromBefore :=> Fixup_Update (That (ComposeMaybe mToAfter))] -- The item is destroyed in the second patch, so indicate that it is destroyed in the source map
134226 (Just toAfter, _) -> [toAfter :=> Fixup_Update (This editBefore)]
135227 (Nothing, _) -> []
136228 mergeFixups _ Fixup_Delete Fixup_Delete = Fixup_Delete
@@ -148,7 +240,13 @@ instance GCompare k => Semigroup (PatchDMapWithMove k v) where
148240 applyFixup _ ni = \case
149241 Fixup_Delete -> Nothing
150242 Fixup_Update u -> Just $ NodeInfo
151− { _nodeInfo_from = fromMaybe (_nodeInfo_from ni) $ getHere u
243+ { _nodeInfo_from = case _nodeInfo_from ni of
244+ f@(From_Move _ p') -> case getHere u of -- The `from` fixup comes from the "old" patch
245+ Nothing -> f -- If there's no `from` fixup, just use the "new" `from`
246+ Just (From_Insert v) -> From_Insert $ applyAlways p' v
247+ Just From_Delete -> From_Delete
248+ Just (From_Move oldKey p) -> From_Move oldKey $ p' <> p
249+ _ -> error "DPatchMapWithMove: fixup for non-move From"
152250 , _nodeInfo_to = fromMaybe (_nodeInfo_to ni) $ getThere u
153251 }
154252 m = DMap.differenceWithKey applyFixup (DMap.unionWithKey combineNodeInfos ma mb) fixups
@@ -169,7 +267,7 @@ instance GCompare k => Monoid (PatchDMapWithMove k v) where
169267 mappend = (<>)
170268
171269{-
172−mappendPatchDMapWithMoveSlow :: forall k v. (ShowTag k v, GCompare k) => PatchDMapWithMove k v -> PatchDMapWithMove k v -> PatchDMapWithMove k v
270+mappendPatchDMapWithMoveSlow :: forall k v. (ShowTag k v, GCompare k) => PatchDMapWithMove k v -> PatchDMapWithMove k v -> PatchDMapWithMove k v
173271PatchDMapWithMove dstAfter srcAfter `mappendPatchDMapWithMoveSlow` PatchDMapWithMove dstBefore srcBefore = PatchDMapWithMove dst src
174272 where
175273 getDstAction k m = fromMaybe (From_Move k) $ DMap.lookup k m -- Any key that isn't present is treated as that key moving to itself
@@ -190,8 +288,8 @@ PatchDMapWithMove dstAfter srcAfter `mappendPatchDMapWithMoveSlow` PatchDMapWith
190288 src = DMap.mapMaybeWithKey g $ DMap.union srcAfter srcBefore
191289-}
192290
193−-- |Make a @'PatchDMapWithMove' k v@ which has the effect of inserting or updating a value @v a@ to the given key @k a@, like 'DMap.insert'.
194−insertDMapKey :: k a -> v a -> PatchDMapWithMove k v
291+-- |Make a @'PatchDMapWithMove' k v@ which has the effect of inserting or updating a value @PatchTarget1 p a@ to the given key @k a@, like 'DMap.insert'.
292+insertDMapKey :: k a -> PatchTarget1 p a -> PatchDMapWithMove k p
195293insertDMapKey k v =
196294 PatchDMapWithMove . DMap.singleton k $ NodeInfo (From_Insert v) (ComposeMaybe Nothing)
197295
@@ -272,41 +370,67 @@ patchDMapWithMove dm =
272370 errs -> Left errs
273371
274372-- |Map a natural transform @v -> v'@ over the given patch, transforming @'PatchDMapWithMove' k v@ into @'PatchDMapWithMove' k v'@.
275−mapPatchDMapWithMove :: forall k v v'. (forall a. v a -> v' a) -> PatchDMapWithMove k v -> PatchDMapWithMove k v'
373+mapPatchDMapWithMove
374+ :: forall k p p'
375+ . (forall a. PatchTarget1 p a -> PatchTarget1 p' a)
376+ -> PatchDMapWithMove k p
377+ -> PatchDMapWithMove k p'
276378mapPatchDMapWithMove f (PatchDMapWithMove p) = PatchDMapWithMove $
277379 DMap.map (\ni -> ni { _nodeInfo_from = g $ _nodeInfo_from ni }) p
278− where g :: forall a. From k v a -> From k v' a
380+ where g :: forall a. From k PatchTarget1 p a -> From k PatchTarget1 p' a
279381 g = \case
280382 From_Insert v -> From_Insert $ f v
281383 From_Delete -> From_Delete
282384 From_Move k -> From_Move k
283385
284−-- |Traverse an effectful function @forall a. v a -> m (v ' a)@ over the given patch, transforming @'PatchDMapWithMove' k v@ into @m ('PatchDMapWithMove' k v')@.
285−traversePatchDMapWithMove :: forall m k v v'. Applicative m => (forall a. v a -> m (v' a)) -> PatchDMapWithMove k v -> m (PatchDMapWithMove k v')
386+-- |Traverse an effectful function @forall a. PatchTarget1 p a -> m (v ' a)@ over the given patch, transforming @'PatchDMapWithMove' k v@ into @m ('PatchDMapWithMove' k v')@.
387+traversePatchDMapWithMove
388+ :: forall m k p p'
389+ . Applicative m
390+ => (forall a. PatchTarget1 p a -> m (PatchTarget1 p' a))
391+ -> PatchDMapWithMove k p
392+ -> m (PatchDMapWithMove k p')
286393traversePatchDMapWithMove f = traversePatchDMapWithMoveWithKey $ const f
287394
288−-- |Map an effectful function @forall a. k a -> v a -> m (v ' a)@ over the given patch, transforming @'PatchDMapWithMove' k v@ into @m ('PatchDMapWithMove' k v')@.
289−traversePatchDMapWithMoveWithKey :: forall m k v v'. Applicative m => (forall a. k a -> v a -> m (v' a)) -> PatchDMapWithMove k v -> m (PatchDMapWithMove k v')
290−traversePatchDMapWithMoveWithKey f (PatchDMapWithMove p) = PatchDMapWithMove <$> DMap.traverseWithKey (nodeInfoMapFromM . g) p
291− where g :: forall a. k a -> From k v a -> m (From k v' a)
395+-- |Map an effectful function @forall a. k a -> PatchTarget1 p a -> m (v ' a)@ over the given patch, transforming @'PatchDMapWithMove' k v@ into @m ('PatchDMapWithMove' k v')@.
396+traversePatchDMapWithMoveWithKey
397+ :: forall m k p p'
398+ . Applicative m
399+ => (forall a. k a -> PatchTarget1 p a -> m (PatchTarget1 p' a))
400+ -> PatchDMapWithMove k p
401+ -> m (PatchDMapWithMove k p')
402+traversePatchDMapWithMoveWithKey f (PatchDMapWithMove p) =
403+ PatchDMapWithMove <$> DMap.traverseWithKey (nodeInfoMapFromM . g) p
404+ where g :: forall a. k a -> From k PatchTarget1 p a -> m (From k PatchTarget1 p' a)
292405 g k = \case
293406 From_Insert v -> From_Insert <$> f k v
294407 From_Delete -> pure From_Delete
295408 From_Move fromKey -> pure $ From_Move fromKey
296409
297−-- |Map a function which transforms @'From' k v a@ into a @'From' k v' a@ over a @'NodeInfo' k v a@.
298−nodeInfoMapFrom :: (From k v a -> From k v' a) -> NodeInfo k v a -> NodeInfo k v' a
410+-- |Map a function which transforms @'From' k PatchTarget1 p a@ into a @'From' k PatchTarget1 p' a@ over a @'NodeInfo' k PatchTarget1 p a@.
411+nodeInfoMapFrom
412+ :: (From k p a -> From k p' a)
413+ -> NodeInfo k p a
414+ -> NodeInfo k p' a
299415nodeInfoMapFrom f ni = ni { _nodeInfo_from = f $ _nodeInfo_from ni }
300416
301−-- |Map an effectful function which transforms @'From' k v a@ into a @f ('From' k v' a)@ over a @'NodeInfo' k v a@.
302−nodeInfoMapFromM :: Functor f => (From k v a -> f (From k v' a)) -> NodeInfo k v a -> f (NodeInfo k v' a)
417+-- |Map an effectful function which transforms @'From' k PatchTarget1 p a@ into a @f ('From' k PatchTarget1 p' a)@ over a @'NodeInfo' k PatchTarget1 p a@.
418+nodeInfoMapFromM
419+ :: Functor f
420+ => (From k p a -> f (From k p' a))
421+ -> NodeInfo k p a
422+ -> f (NodeInfo k p' a)
303423nodeInfoMapFromM f ni = fmap (\result -> ni { _nodeInfo_from = result }) $ f $ _nodeInfo_from ni
304424
305−-- |Weaken a 'PatchDMapWithMove' to a 'PatchMapWithMove' by weakening the keys from @k a@ to @'Some' k@ and applying a given weakening function @v a -> v'@ to
425+-- |Weaken a 'PatchDMapWithMove' to a 'PatchMapWithMove' by weakening the keys from @k a@ to @'Some' k@ and applying a given weakening function @PatchTarget1 p a -> v'@ to
306426-- values.
307−weakenPatchDMapWithMoveWith :: forall k v v'. (forall a. v a -> v') -> PatchDMapWithMove k v -> PatchMapWithMove (Some k) (Proxy v')
427+weakenPatchDMapWithMoveWith
428+ :: forall k p v'
429+ . (forall a. PatchTarget1 p a -> v')
430+ -> PatchDMapWithMove k p
431+ -> PatchMapWithMove (Some k) (Proxy v')
308432weakenPatchDMapWithMoveWith f (PatchDMapWithMove p) = PatchMapWithMove $ weakenDMapWith g p
309− where g :: forall a. NodeInfo k v a -> MapWithMove.NodeInfo (Some k) (Proxy v')
433+ where g :: forall a. NodeInfo k PatchTarget1 p a -> MapWithMove.NodeInfo (Some k) (Proxy v')
310434 g ni = MapWithMove.NodeInfo
311435 { MapWithMove._nodeInfo_from = case _nodeInfo_from ni of
312436 From_Insert v -> MapWithMove.From_Insert $ f v
@@ -317,9 +441,12 @@ weakenPatchDMapWithMoveWith f (PatchDMapWithMove p) = PatchMapWithMove $ weakenD
317441
318442-- |"Weaken" a @'PatchDMapWithMove' (Const2 k a) v@ to a @'PatchMapWithMove' k v'@. Weaken is in scare quotes because the 'Const2' has already disabled any
319443-- dependency in the typing and all points are already @a@, hence the function to map each value to @v'@ is not higher rank.
320−patchDMapWithMoveToPatchMapWithMoveWith :: forall k v v' a. (v a -> v') -> PatchDMapWithMove (Const2 k a) v -> PatchMapWithMove k (Proxy v')
444+patchDMapWithMoveToPatchMapWithMoveWith
445+ :: forall k p v' a. (PatchTarget1 p a -> v')
446+ -> PatchDMapWithMove (Const2 k a) p
447+ -> PatchMapWithMove k (Proxy v')
321448patchDMapWithMoveToPatchMapWithMoveWith f (PatchDMapWithMove p) = PatchMapWithMove $ dmapToMapWith g p
322− where g :: NodeInfo (Const2 k a) v a -> MapWithMove.NodeInfo k (Proxy v')
449+ where g :: NodeInfo (Const2 k a) PatchTarget1 p a -> MapWithMove.NodeInfo k (Proxy v')
323450 g ni = MapWithMove.NodeInfo
324451 { MapWithMove._nodeInfo_from = case _nodeInfo_from ni of
325452 From_Insert v -> MapWithMove.From_Insert $ f v
@@ -329,9 +456,13 @@ patchDMapWithMoveToPatchMapWithMoveWith f (PatchDMapWithMove p) = PatchMapWithMo
329456 }
330457
331458-- |"Strengthen" a @'PatchMapWithMove' k v@ into a @'PatchDMapWithMove ('Const2' k a)@; that is, turn a non-dependently-typed patch into a dependently typed
332−-- one but which always has a constant key type represented by 'Const2'. Apply the given function to each @v@ to produce a @v' a@.
459+-- one but which always has a constant key type represented by 'Const2'. Apply the given function to each @v@ to produce a @PatchTarget1 p' a@.
333460-- Completemented by 'patchDMapWithMoveToPatchMapWithMoveWith'
334−const2PatchDMapWithMoveWith :: forall k v v' a. (v -> v' a) -> PatchMapWithMove k (Proxy v) -> PatchDMapWithMove (Const2 k a) v'
461+const2PatchDMapWithMoveWith
462+ :: forall k v p' a
463+ . (v -> PatchTarget1 p' a)
464+ -> PatchMapWithMove k (Proxy v)
465+ -> PatchDMapWithMove (Const2 k a) p'
335466const2PatchDMapWithMoveWith f (PatchMapWithMove p) = PatchDMapWithMove $ DMap.fromDistinctAscList $ g <$> Map.toAscList p
336467 where g :: (k, MapWithMove.NodeInfo k (Proxy v)) -> DSum (Const2 k a) (NodeInfo (Const2 k a) v')
337468 g (k, ni) = Const2 k :=> NodeInfo
@@ -343,17 +474,19 @@ const2PatchDMapWithMoveWith f (PatchMapWithMove p) = PatchDMapWithMove $ DMap.fr
343474 }
344475
345476-- | Apply the insertions, deletions, and moves to a given 'DMap'.
346−instance GCompare k => Patch (PatchDMapWithMove k v) where
347− type PatchTarget (PatchDMapWithMove k v) = DMap k v
477+instance GCompare k => PatchHet (PatchDMapWithMove k p) where
478+ type PatchSource (PatchDMapWithMove k p) = DMap k (PatchSource1 p)
479+ type PatchTarget (PatchDMapWithMove k p) = DMap k (PatchTarget1 p)
480+instance GCompare k => Patch (PatchDMapWithMove k p) where
348481 apply (PatchDMapWithMove p) old = Just $! insertions `DMap.union` (old `DMap.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?
349482 where insertions = DMap.mapMaybeWithKey insertFunc p
350− insertFunc :: forall a. k a -> NodeInfo k v a -> Maybe (v a)
483+ insertFunc :: forall a. k a -> NodeInfo k p a -> Maybe (PatchTarget1 p a)
351484 insertFunc _ ni = case _nodeInfo_from ni of
352485 From_Insert v -> Just v
353486 From_Move k -> DMap.lookup k old
354487 From_Delete -> Nothing
355488 deletions = DMap.mapMaybeWithKey deleteFunc p
356− deleteFunc :: forall a. k a -> NodeInfo k v a -> Maybe (Constant () a)
489+ deleteFunc :: forall a. k a -> NodeInfo k p a -> Maybe (Constant () a)
357490 deleteFunc _ ni = case _nodeInfo_from ni of
358491 From_Delete -> Just $ Constant ()
359492 _ -> Nothing
src/Data/Patch/DMapWithReset.hsnew file+120
@@ -0,0 +1,120 @@
1+{-# LANGUAGE FlexibleContexts #-}
2+{-# LANGUAGE FlexibleInstances #-}
3+{-# LANGUAGE LambdaCase #-}
4+{-# LANGUAGE MultiParamTypeClasses #-}
5+{-# LANGUAGE PolyKinds #-}
6+{-# LANGUAGE Rank2Types #-}
7+{-# LANGUAGE ScopedTypeVariables #-}
8+{-# LANGUAGE StandaloneDeriving #-}
9+{-# LANGUAGE TypeApplications #-}
10+{-# LANGUAGE TypeFamilies #-}
11+{-# LANGUAGE UndecidableInstances #-}
12+
13+{-# OPTIONS_GHC -Wall #-}
14+
15+-- | 'Patch'es on 'DMap' that consist only of insertions (or overwrites) and deletions.
16+module Data.Patch.DMapWithReset where
17+
18+import Data.Patch.Class
19+
20+import Data.Dependent.Map (DMap, GCompare (..))
21+import qualified Data.Dependent.Map as DMap
22+import Data.Semigroup (Semigroup (..))
23+import Data.Constraint.Extras
24+
25+-- | A set of changes to a 'DMap'. Any element may be inserted/updated or deleted.
26+-- Insertions are represented as @'ComposeMaybe' (Just value)@,
27+-- while deletions are represented as @'ComposeMaybe' Nothing@.
28+newtype PatchDMapWithReset k p = PatchDMapWithReset { unPatchDMapWithReset :: DMap k (By p) }
29+
30+-- | Holds the information about each key: where its new value should come from,
31+-- and where its old value should go to
32+data By p a
33+ = By_Insert (PatchTarget (p a)) -- ^ Insert the given value here
34+ | By_Delete -- ^ Delete the existing value, if any, from here
35+ | By_Patch (p a) -- ^ Patch the value here with the given patch
36+
37+instance (Semigroup (p a), Patch (p a)) => Semigroup (By p a) where
38+ x@(By_Insert _) <> _ = x
39+ By_Delete <> _ = By_Delete
40+ By_Patch x <> By_Insert y = By_Insert (applyAlways x y)
41+ By_Patch x <> By_Patch y = By_Patch (x <> y)
42+ By_Patch _ <> By_Delete = By_Delete
43+
44+instance (Monoid (p a), Patch (p a)) => Monoid (By p a) where
45+ mappend = (<>)
46+ mempty = By_Patch mempty
47+
48+instance
49+ ( GCompare k
50+ , Has' Semigroup k p
51+ , Has' Patch k p
52+ )
53+ => Semigroup (PatchDMapWithReset k p) where
54+ PatchDMapWithReset xs <> PatchDMapWithReset ys = PatchDMapWithReset $ DMap.unionWithKey
55+ (\k -> has' @Patch @p k
56+ $ has' @Semigroup @p k
57+ $ (<>)) xs ys
58+
59+instance
60+ ( GCompare k
61+ , Has' Semigroup k p
62+ , Has' Patch k p
63+ )
64+ => Monoid (PatchDMapWithReset k p) where
65+ mappend = (<>)
66+ mempty = PatchDMapWithReset DMap.empty
67+
68+class (Patch (p a), PatchTarget (p a) ~ Patches1LocallyTarget p a) => Patches1Locally p a where
69+ type Patches1LocallyTarget p :: k -> *
70+
71+data These1 f g x
72+ = This1 (f x)
73+ | That1 (g x)
74+ | These1 (f x) (g x)
75+
76+mergeWithKey
77+ :: forall k v1 v2 v.
78+ (GCompare k)
79+ => (forall x. k x -> v1 x -> Maybe (v x))
80+ -> (forall x. k x -> v2 x -> Maybe (v x))
81+ -> (forall x. k x -> v1 x -> v2 x -> Maybe (v x))
82+ -> DMap k v1 -> DMap k v2 -> DMap k v
83+mergeWithKey f g fg = \xs ys -> DMap.mapMaybeWithKey onlyThat $ DMap.unionWithKey doIt (DMap.map This1 xs) (DMap.map That1 ys)
84+ where
85+ doIt _ (This1 xs) (That1 ys) = These1 xs ys
86+ doIt _ _ _ = error "mergeWithKey misalligned keys"
87+
88+ onlyThat :: forall x. k x -> These1 v1 v2 x -> Maybe (v x)
89+ onlyThat k = \case
90+ This1 xs -> f k xs
91+ That1 ys -> g k ys
92+ These1 xs ys -> fg k xs ys
93+{-# INLINE mergeWithKey #-}
94+
95+-- | Apply the insertions or deletions to a given 'DMap'.
96+instance (GCompare k, Has (Patches1Locally p) k) => Patch (PatchDMapWithReset k p) where
97+
98+ type PatchTarget (PatchDMapWithReset k p) = DMap k (Patches1LocallyTarget p)
99+
100+ apply = go
101+ where
102+ go :: PatchDMapWithReset k p -> DMap k (Patches1LocallyTarget p) -> Maybe (DMap k (Patches1LocallyTarget p))
103+ go (PatchDMapWithReset diff) old = Just $! mergeWithKey (\_ -> Just) inserts updates old diff
104+ where
105+ updates :: forall x. k x -> Patches1LocallyTarget p x -> By p x -> Maybe (Patches1LocallyTarget p x)
106+ updates k ys = has @(Patches1Locally p) k $ \case
107+ By_Insert x -> Just x
108+ By_Delete -> Nothing
109+ By_Patch x -> Just $ applyAlways x ys
110+
111+ inserts :: forall x. k x -> By p x -> Maybe (Patches1LocallyTarget p x)
112+ inserts k = has @(Patches1Locally p) k $ \case
113+ By_Insert x -> Just x
114+ By_Delete -> Nothing
115+ By_Patch _ -> Nothing
116+
117+deriving instance (Patch (p a), Eq (p a), Eq (PatchTarget (p a))) => Eq (By p a)
118+deriving instance (Patch (p a), Show (p a), Show (PatchTarget (p a))) => Show (By p a)
119+deriving instance (Eq (DMap k (By p))) => Eq (PatchDMapWithReset k p)
120+deriving instance (Show (DMap k (By p))) => Show (PatchDMapWithReset k p)
src/Data/Patch/IntMap.hs+3−1
@@ -19,8 +19,10 @@ import Data.Patch.Class
1919newtype PatchIntMap a = PatchIntMap (IntMap (Maybe a)) deriving (Functor, Foldable, Traversable, Monoid)
2020
2121-- | Apply the insertions or deletions to a given 'IntMap'.
22−instance Patch (PatchIntMap a) where
22+instance PatchHet (PatchIntMap a) where
23+ type PatchSource (PatchIntMap a) = IntMap a
2324 type PatchTarget (PatchIntMap a) = IntMap a
25+instance Patch (PatchIntMap a) where
2426 apply (PatchIntMap p) v = if IntMap.null p then Nothing else Just $
2527 let removes = IntMap.filter isNothing p
2628 adds = IntMap.mapMaybe id p
src/Data/Patch/Map.hs+3−1
@@ -18,8 +18,10 @@ newtype PatchMap k v = PatchMap { unPatchMap :: Map k (Maybe v) }
1818 deriving (Show, Read, Eq, Ord)
1919
2020-- | Apply the insertions or deletions to a given 'Map'.
21−instance Ord k => Patch (PatchMap k v) where
21+instance Ord k => PatchHet (PatchMap k v) where
22+ type PatchSource (PatchMap k v) = Map k v
2223 type PatchTarget (PatchMap k v) = Map k v
24+instance Ord k => Patch (PatchMap k v) where
2325 {-# INLINABLE apply #-}
2426 apply (PatchMap 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?
2527 where insertions = Map.mapMaybeWithKey (const id) p
src/Data/Patch/MapWithMove.hs+8−3
@@ -142,9 +142,15 @@ unsafePatchMapWithMove
142142unsafePatchMapWithMove = PatchMapWithMove
143143
144144-- | Apply the insertions, deletions, and moves to a given 'Map'
145−instance (Ord k, Patch p) => Patch (PatchMapWithMove k p) where
145+instance (Ord k, Patch p) => PatchHet (PatchMapWithMove k p) where
146+ type PatchSource (PatchMapWithMove k p) = Map k (PatchSource p)
146147 type PatchTarget (PatchMapWithMove k p) = Map k (PatchTarget p)
147− apply (PatchMapWithMove m) 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?
148+instance (Ord k, Patch p) => Patch (PatchMapWithMove k p) where
149+ -- TODO: return Nothing sometimes
150+ -- Note: the strict application here is critical to ensuring that incremental
151+ -- merges don't hold onto all their prerequisite events forever; can we make
152+ -- this more robust?
153+ apply (PatchMapWithMove m) old = Just $! insertions `Map.union` (old `Map.difference` deletions)
148154 where insertions = flip Map.mapMaybeWithKey m $ \_ ni -> case _nodeInfo_from ni of
149155 From_Insert v -> Just v
150156 From_Move k p -> applyAlways p <$> Map.lookup k old
@@ -252,7 +258,6 @@ data Fixup k v
252258
253259-- |Compose patches having the same effect as applying the patches in turn: @'applyAlways' (p <> q) == 'applyAlways' p . 'applyAlways' q@
254260instance ( Ord k
255− , Monoid p
256261 , DecidablyEmpty p
257262 , Patch p
258263 ) => Semigroup (PatchMapWithMove k p) where
src/Data/Patch/Patchable.hsnew file+45
@@ -0,0 +1,45 @@
1+{-# LANGUAGE DeriveGeneric #-}
2+{-# LANGUAGE FlexibleContexts #-}
3+{-# LANGUAGE LambdaCase #-}
4+{-# LANGUAGE StandaloneDeriving #-}
5+{-# LANGUAGE TypeFamilies #-}
6+
7+-- The derived instances are undecidable in the case of a pathological instance like
8+-- instance Patch x where
9+-- type PatchTarget x = Patchable x
10+{-# LANGUAGE UndecidableInstances #-}
11+
12+module Data.Patch.Patchable where
13+
14+-- import Data.Aeson
15+import GHC.Generics
16+
17+import Data.Patch
18+
19+-- | Like SemiMap/PartialMap but for anything patchable
20+data Patchable p
21+ = Patchable_Patch p
22+ | Patchable_Complete (PatchTarget p)
23+ deriving (Generic)
24+
25+completePatchable :: Patchable p -> Maybe (PatchTarget p)
26+completePatchable = \case
27+ Patchable_Complete t -> Just t
28+ Patchable_Patch _ -> Nothing
29+
30+deriving instance (Eq p, Eq (PatchTarget p)) => Eq (Patchable p)
31+deriving instance (Ord p, Ord (PatchTarget p)) => Ord (Patchable p)
32+deriving instance (Show p, Show (PatchTarget p)) => Show (Patchable p)
33+deriving instance (Read p, Read (PatchTarget p)) => Read (Patchable p)
34+-- instance (ToJSON p, ToJSON (PatchTarget p)) => ToJSON (Patchable p)
35+-- instance (FromJSON p, FromJSON (PatchTarget p)) => FromJSON (Patchable p)
36+
37+instance (Monoid p, Patch p) => Monoid (Patchable p) where
38+ mempty = Patchable_Patch mempty
39+ mappend = (<>)
40+
41+instance (Semigroup p, Patch p) => Semigroup (Patchable p) where
42+ (<>) = curry $ \case
43+ (Patchable_Patch a, Patchable_Patch b) -> Patchable_Patch $ a <> b
44+ (Patchable_Patch a, Patchable_Complete b) -> Patchable_Complete $ applyAlways a b
45+ (Patchable_Complete a, _) -> Patchable_Complete a