idris2-profunctors/Data/Profunctor/Strong.idr
2023-03-06 10:51:03 -05:00

133 lines
3.7 KiB
Idris

module Data.Profunctor.Strong
import Data.Tensor
import Data.Profunctor.Functor
import Data.Profunctor.Types
%default total
public export
interface Profunctor p => GenStrong (0 ten : Type -> Type -> Type) p where
strongl : p a b -> p (a `ten` c) (b `ten` c)
strongr : p a b -> p (c `ten` a) (c `ten` b)
public export
Strong : (p : Type -> Type -> Type) -> Type
Strong = GenStrong Pair
public export
first : Strong p => p a b -> p (a, c) (b, c)
first = strongl {ten=Pair}
public export
second : Strong p => p a b -> p (c, a) (c, b)
second = strongr {ten=Pair}
export
uncurry' : Strong p => p a (b -> c) -> p (a, b) c
uncurry' = rmap (uncurry id) . first
-- Tambara
public export
record GenTambara (ten, p : Type -> Type -> Type) a b where
constructor MkTambara
getTambara : {0 c : Type} -> p (a `ten` c) (b `ten` c)
export
Bifunctor ten => Profunctor p => Profunctor (GenTambara ten p) where
dimap f g (MkTambara p) = MkTambara $ dimap (mapFst f) (mapFst g) p
export
ProfunctorFunctor (GenTambara ten) where
promap f (MkTambara p) = MkTambara (f p)
export
Tensor ten i => ProfunctorComonad (GenTambara ten) where
proextract (MkTambara p) = dimap unitr.bwd unitr.fwd p
produplicate (MkTambara p) = MkTambara $ MkTambara $ dimap assoc.bwd assoc.fwd p
export
Associative ten => Symmetric ten => Profunctor p => GenStrong ten (GenTambara ten p) where
strongl (MkTambara p) = MkTambara $ dimap assoc.bwd assoc.fwd p
strongr = dimap swap swap . strongl {ten,p=GenTambara ten p}
export
Bifunctor ten => Profunctor p => Functor (GenTambara ten p a) where
map = rmap
export
gentambara : GenStrong ten p => p :-> q -> p :-> GenTambara ten q
gentambara @{gs} f x = MkTambara $ f $ strongl @{gs} x
export
ungentambara : Tensor ten i => Profunctor q => p :-> GenTambara ten q -> p :-> q
ungentambara f x = dimap unitr.bwd unitr.fwd $ getTambara $ f x
public export
Tambara : (p : Type -> Type -> Type) -> Type
Tambara = GenTambara Pair
-- Pastro
public export
data GenPastro : (ten, p : Type -> Type -> Type) -> Type -> Type -> Type where
MkPastro : (y `ten` z -> b) -> p x y -> (a -> x `ten` z) -> GenPastro ten p a b
export
Profunctor (GenPastro ten p) where
dimap f g (MkPastro l m r) = MkPastro (g . l) m (r . f)
lmap f (MkPastro l m r) = MkPastro l m (r . f)
rmap g (MkPastro l m r) = MkPastro (g . l) m r
export
ProfunctorFunctor (GenPastro ten) where
promap f (MkPastro l m r) = MkPastro l (f m) r
export
(Tensor ten i, Symmetric ten) => ProfunctorMonad (GenPastro ten) where
propure x = MkPastro unitr.fwd x unitr.bwd
projoin (MkPastro {x=x',y=y',z=z'} l' (MkPastro {x,y,z} l m r) r') = MkPastro ll m rr
where
ll : y `ten` (z' `ten` z) -> b
ll = l' . mapFst l . assoc.fwd . mapSnd swap
rr : a -> x `ten` (z' `ten` z)
rr = mapSnd swap . assoc.bwd . mapFst r . r'
export
ProfunctorAdjunction (GenPastro ten) (GenTambara ten) where
prounit x = MkTambara (MkPastro id x id)
procounit (MkPastro l (MkTambara x) r) = dimap r l x
export
(Associative ten, Symmetric ten) => GenStrong ten (GenPastro ten p) where
strongl (MkPastro {x,y,z} l m r) = MkPastro l' m r'
where
l' : y `ten` (z `ten` c) -> b `ten` c
l' = mapFst l . assoc.fwd
r' : a `ten` c -> x `ten` (z `ten` c)
r' = assoc.bwd . mapFst r
strongr (MkPastro {x,y,z} l m r) = MkPastro l' m r'
where
l' : y `ten` (c `ten` z) -> c `ten` b
l' = swap . mapFst l . assoc.fwd . mapSnd swap
r' : c `ten` a -> x `ten` (c `ten` z)
r' = mapSnd swap . assoc.bwd . mapFst r . swap
export
genpastro : GenStrong ten q => p :-> q -> GenPastro ten p :-> q
genpastro @{gs} f (MkPastro l m r) = dimap r l (strongl @{gs} (f m))
export
ungenpastro : Tensor ten i => GenPastro ten p :-> q -> p :-> q
ungenpastro f x = f (MkPastro unitr.fwd x unitr.bwd)