{-# LANGUAGE MultiParamTypeClasses, FlexibleInstances, UndecidableInstances #-} {- | /DEPRECATED/: Use "Data.Generics.Uniplate.Typeable" instead. This module supplies a method for writing 'Biplate' instances more easily. To take an example: > data Expr = Var Int | Neg Expr | Add Expr Expr > > instance Typeable Expr where ... > > instance (Typeable a, Uniplate a) => PlateAll Expr a where > plateAll (Var x ) = plate Var |- x > plateAll (Neg x ) = plate Neg |+ x > plateAll (Add x y) = plate Add |+ x |+ y > > instance Uniplate Expr where > uniplate = uniplateAll -} module Data.Generics.PlateTypeable {-# DEPRECATED "Use Data.Generics.Uniplate.Typeable instead" #-} ( module Data.Generics.Biplate, module Data.Typeable, -- * The Class PlateAll(..), uniplateAll, -- * The Combinators plate, (|+), (|-) ) where import Data.Generics.Biplate import Data.Generics.Uniplate.Internal.Utils import Data.Typeable instance (Typeable a, Typeable b, Uniplate b, PlateAll a b) => Biplate a b where biplate = plateMore -- | This function is used to write a 'Uniplate' instance from a 'PlateAll' one uniplateAll :: PlateAll a b => a -> (Str b, Str b -> a) uniplateAll = plateAll type Type from to = (Str to, Str to -> from) plateMore :: (Typeable from, Typeable to, PlateAll from to) => from -> Type from to plateMore x = res where res = case asTypeOf (cast x) (Just $ strType $ fst res) of Nothing -> plateAll x Just y -> (One y, \(One y) -> unsafeCoerce y) -- | This class represents going from the container type to the target. -- -- This class should only be constructed with 'plate', '|+' and '|-' class PlateAll from to where plateAll :: from -> Type from to -- | The main combinator used to start the chain. -- -- The following rule can be used for optimisation: -- -- > plate Ctor |- x == plate (Ctor x) plate :: from -> Type from to plate x = (Zero, \_ -> x) -- | the field to the right may contain the target. (|+) :: (Typeable item, Typeable to, PlateAll item to) => Type (item -> from) to -> item -> Type from to (|+) (xs,x_) y = case plateMore y of (ys,y_) -> (Two xs ys,\(Two xs ys) -> x_ xs (y_ ys)) -- | The field to the right /does not/ contain the target. -- This can be used as either an optimisation, or more commonly for excluding -- primitives such as Int. (|-) :: Type (item -> from) to -> item -> Type from to (|-) (xs,x_) y = (xs,\xs -> x_ xs y) -- * Instances -- ** Primitive Types instance PlateAll Int to where plateAll x = plate x instance Uniplate Int where uniplate = uniplateAll instance PlateAll Bool to where plateAll x = plate x instance Uniplate Bool where uniplate = uniplateAll instance PlateAll Char to where plateAll x = plate x instance Uniplate Char where uniplate = uniplateAll instance PlateAll Integer to where plateAll x = plate x instance Uniplate Integer where uniplate = uniplateAll instance PlateAll Double to where plateAll x = plate x instance Uniplate Double where uniplate = uniplateAll instance PlateAll Float to where plateAll x = plate x instance Uniplate Float where uniplate = uniplateAll instance PlateAll () to where plateAll x = plate x instance Uniplate () where uniplate = uniplateAll -- ** Container Types instance (PlateAll from to, Typeable from, Typeable to, Uniplate to) => PlateAll [from] to where plateAll [] = plate [] plateAll (x:xs) = plate (:) |+ x |+ xs instance (PlateAll from to, Typeable from, Typeable to, Uniplate to) => PlateAll (Maybe from) to where plateAll Nothing = plate Nothing plateAll (Just x) = plate Just |+ x instance (PlateAll a to, Typeable a, PlateAll b to, Typeable b, Typeable to, Uniplate to) => PlateAll (Either a b) to where plateAll (Left x) = plate Left |+ x plateAll (Right x) = plate Right |+ x instance (PlateAll a to, Typeable a ,PlateAll b to, Typeable b ,Typeable to, Uniplate to) => PlateAll (a,b) to where plateAll (a,b) = plate (,) |+ a |+ b instance (PlateAll a to, Typeable a ,PlateAll b to, Typeable b ,PlateAll c to, Typeable c ,Typeable to, Uniplate to) => PlateAll (a,b,c) to where plateAll (a,b,c) = plate (,,) |+ a |+ b |+ c instance (PlateAll a to, Typeable a ,PlateAll b to, Typeable b ,PlateAll c to, Typeable c ,PlateAll d to, Typeable d ,Typeable to, Uniplate to) => PlateAll (a,b,c,d) to where plateAll (a,b,c,d) = plate (,,,) |+ a |+ b |+ c |+ d instance (PlateAll a to, Typeable a ,PlateAll b to, Typeable b ,PlateAll c to, Typeable c ,PlateAll d to, Typeable d ,PlateAll e to, Typeable e ,Typeable to, Uniplate to) => PlateAll (a,b,c,d,e) to where plateAll (a,b,c,d,e) = plate (,,,,) |+ a |+ b |+ c |+ d |+ e