@@ -22,11 +22,14 @@ import Control.Applicative
22import Data.Coerce
22import Data.Coerce
23import Data.Functor.Identity
23import Data.Functor.Identity
24import Data.Kind
24import Data.Kind
25−import Data.List as List
26import Data.Tagged
25import Data.Tagged
27−import Data.Traversable
28import GHC.Exts (Constraint)
26import GHC.Exts (Constraint)
29−import qualified Language.Haskell.TH as TH
27+
28+import Ether.Internal.HasLens
29+import Ether.Internal.Tags
30+import Ether.Internal.TupleInstances_Tags ()
31+import Ether.Internal.TupleInstances_TagsK ()
32+import Ether.Internal.TupleInstances_HasLens ()
31data TAGGED e t
34data TAGGED e t
@@ -54,120 +57,12 @@ class
55 handling :: Monad m => (HandleConstraint eff p trans m => r) -> r
58 handling :: Monad m => (HandleConstraint eff p trans m => r) -> r
57−type LensLike f s t a b = (a -> f b) -> s -> f t
59−type Lens s t a b = forall f. Functor f => LensLike f s t a b
61−type Lens' s a = Lens s s a a
63newtype ReifiedLens s t a b = Lens (Lens s t a b)
60newtype ReifiedLens s t a b = Lens (Lens s t a b)
65type ReifiedLens' s a = ReifiedLens s s a a
62type ReifiedLens' s a = ReifiedLens s s a a
67−class HasLens tag outer inner | tag outer -> inner where
68− lensOf :: Lens' outer inner
70−instance HasLens a a a where
73−instance HasLens t (Tagged t a) a where
74− lensOf = \f -> fmap coerce . f . coerce
76view :: LensLike (Const a) s t a b -> s -> a
64view :: LensLike (Const a) s t a b -> s -> a
77view l = coerce (l Const)
65view l = coerce (l Const)
79over :: LensLike Identity s t a b -> (a -> b) -> s -> t
67over :: LensLike Identity s t a b -> (a -> b) -> s -> t
80over = coerce
68over = coerce
84− HCons :: x -> HList xs -> HList (x ': xs)
86−type KindOf (a :: k) = k
88−type family TagsK (p :: Type) :: [Type]
89−type family Tags (p :: Type) :: HList (TagsK p)
93−type instance TagsK () = '[]
94−type instance TagsK (Tagged t a) = '[KindOf t]
99− varName k = TH.mkName ('a' : show k)
100− tagName k = TH.mkName ('t' : show k)
101− for [2..tupCount] $ \n -> do
103− tupTy = List.foldl' TH.AppT (TH.ConT (TH.tupleTypeName n)) $
104− (\k -> TH.ConT ''Tagged `TH.AppT`
105− TH.VarT (tagName k) `TH.AppT`
106− TH.VarT (varName k)) <$> [0..n-1]
107− tagsList = List.foldr
108− (\a b -> TH.PromotedConsT `TH.AppT` a `TH.AppT` b)
110− (TH.AppT (TH.ConT ''KindOf) . TH.VarT . tagName <$> [0..n-1])
112− TH.TySynInstD ''TagsK (TH.TySynEqn [tupTy] tagsList)
116−type instance Tags () = 'HNil
117−type instance Tags (Tagged t a) = 'HCons t 'HNil
122− varName k = TH.mkName ('a' : show k)
123− tagName k = TH.mkName ('t' : show k)
124− for [2..tupCount] $ \n -> do
126− tupTy = List.foldl' TH.AppT (TH.ConT (TH.tupleTypeName n)) $
127− (\k -> TH.ConT ''Tagged `TH.AppT`
128− TH.VarT (tagName k) `TH.AppT`
129− TH.VarT (varName k)) <$> [0..n-1]
130− tagsList = List.foldr
131− (\a b -> TH.PromotedT 'HCons `TH.AppT` a `TH.AppT` b)
132− (TH.PromotedT 'HNil)
133− (TH.VarT . tagName <$> [0..n-1])
135− TH.TySynInstD ''Tags (TH.TySynEqn [tupTy] tagsList)
140− varName k = TH.mkName ('a' : show k)
142− for [2..tupCount] $ \n ->
143− for [0..n-1] $ \k -> do
145− tag = TH.mkName "tag"
146− prev = varName <$> [0..k-1]
148− next = varName <$> [k+1..n-1]
149− tupTy = foldl TH.AppT (TH.ConT (TH.tupleTypeName n))
150− ( map TH.VarT prev ++
151− [TH.ConT ''Tagged `TH.AppT` TH.VarT tag `TH.AppT` TH.VarT cur] ++
154− cur' = TH.mkName "x"
157− TH.InstanceD Nothing []
158− (TH.ConT ''HasLens `TH.AppT` TH.VarT tag `TH.AppT` tupTy `TH.AppT` TH.VarT cur)
162− ( map TH.VarP prev ++
163− [TH.ConP 'Tagged [TH.VarP cur]] ++
166− TH.VarE 'fmap `TH.AppE`
167− (TH.LamE [TH.VarP cur']
169− ( map TH.VarE prev ++
170− [TH.ConE 'Tagged `TH.AppE` TH.VarE cur'] ++
171− map TH.VarE next ))) `TH.AppE`
172− (TH.VarE f `TH.AppE` TH.VarE cur) )