lens-4.19.2: Lenses, Folds and Traversals
Copyright(C) 2012-2016 Edward Kmett
LicenseBSD-style (see the file LICENSE)
MaintainerEdward Kmett <ekmett@gmail.com>
Stabilityexperimental
Portabilitynon-portable
Safe HaskellSafe-Inferred
LanguageHaskell2010

Control.Lens.Internal.Indexed

Description

Internal implementation details for Indexed lens-likes

Synopsis

An Indexed Profunctor

newtype Indexed i a b #

A function with access to a index. This constructor may be useful when you need to store an Indexable in a container to avoid ImpredicativeTypes.

index :: Indexed i a b -> i -> a -> b

Constructors

Indexed 

Fields

Instances

Instances details
i ~ j => Indexable i (Indexed j) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

indexed :: Indexed j a b -> i -> a -> b #

Arrow (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

arr :: (b -> c) -> Indexed i b c #

first :: Indexed i b c -> Indexed i (b, d) (c, d) #

second :: Indexed i b c -> Indexed i (d, b) (d, c) #

(***) :: Indexed i b c -> Indexed i b' c' -> Indexed i (b, b') (c, c') #

(&&&) :: Indexed i b c -> Indexed i b c' -> Indexed i b (c, c') #

ArrowChoice (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

left :: Indexed i b c -> Indexed i (Either b d) (Either c d) #

right :: Indexed i b c -> Indexed i (Either d b) (Either d c) #

(+++) :: Indexed i b c -> Indexed i b' c' -> Indexed i (Either b b') (Either c c') #

(|||) :: Indexed i b d -> Indexed i c d -> Indexed i (Either b c) d #

ArrowApply (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

app :: Indexed i (Indexed i b c, b) c #

ArrowLoop (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

loop :: Indexed i (b, d) (c, d) -> Indexed i b c #

Profunctor (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

dimap :: (a -> b) -> (c -> d) -> Indexed i b c -> Indexed i a d #

lmap :: (a -> b) -> Indexed i b c -> Indexed i a c #

rmap :: (b -> c) -> Indexed i a b -> Indexed i a c #

(#.) :: forall a b c q. Coercible c b => q b c -> Indexed i a b -> Indexed i a c #

(.#) :: forall a b c q. Coercible b a => Indexed i b c -> q a b -> Indexed i a c #

Representable (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Associated Types

type Rep (Indexed i) :: Type -> Type #

Methods

tabulate :: (d -> Rep (Indexed i) c) -> Indexed i d c #

Corepresentable (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Associated Types

type Corep (Indexed i) :: Type -> Type #

Methods

cotabulate :: (Corep (Indexed i) d -> c) -> Indexed i d c #

Choice (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

left' :: Indexed i a b -> Indexed i (Either a c) (Either b c) #

right' :: Indexed i a b -> Indexed i (Either c a) (Either c b) #

Closed (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

closed :: Indexed i a b -> Indexed i (x -> a) (x -> b) #

Strong (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

first' :: Indexed i a b -> Indexed i (a, c) (b, c) #

second' :: Indexed i a b -> Indexed i (c, a) (c, b) #

Costrong (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

unfirst :: Indexed i (a, d) (b, d) -> Indexed i a b #

unsecond :: Indexed i (d, a) (d, b) -> Indexed i a b #

Conjoined (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

distrib :: Functor f => Indexed i a b -> Indexed i (f a) (f b) #

conjoined :: (Indexed i ~ (->) => q (a -> b) r) -> q (Indexed i a b) r -> q (Indexed i a b) r #

Bizarre (Indexed Int) Mafic # 
Instance details

Defined in Control.Lens.Internal.Magma

Methods

bazaar :: Applicative f => Indexed Int a (f b) -> Mafic a b t -> f t #

Category (Indexed i :: Type -> Type -> Type) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

id :: forall (a :: k). Indexed i a a #

(.) :: forall (b :: k) (c :: k) (a :: k). Indexed i b c -> Indexed i a b -> Indexed i a c #

Cosieve (Indexed i) ((,) i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

cosieve :: Indexed i a b -> (i, a) -> b #

Sellable (Indexed i) (Molten i) # 
Instance details

Defined in Control.Lens.Internal.Magma

Methods

sell :: Indexed i a (Molten i a b b) #

Bizarre (Indexed i) (Molten i) # 
Instance details

Defined in Control.Lens.Internal.Magma

Methods

bazaar :: Applicative f => Indexed i a (f b) -> Molten i a b t -> f t #

Sieve (Indexed i) ((->) i :: Type -> Type) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

sieve :: Indexed i a b -> a -> i -> b #

Monad (Indexed i a) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

(>>=) :: Indexed i a a0 -> (a0 -> Indexed i a b) -> Indexed i a b #

(>>) :: Indexed i a a0 -> Indexed i a b -> Indexed i a b #

return :: a0 -> Indexed i a a0 #

Functor (Indexed i a) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

fmap :: (a0 -> b) -> Indexed i a a0 -> Indexed i a b #

(<$) :: a0 -> Indexed i a b -> Indexed i a a0 #

MonadFix (Indexed i a) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

mfix :: (a0 -> Indexed i a a0) -> Indexed i a a0 #

Applicative (Indexed i a) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

pure :: a0 -> Indexed i a a0 #

(<*>) :: Indexed i a (a0 -> b) -> Indexed i a a0 -> Indexed i a b #

liftA2 :: (a0 -> b -> c) -> Indexed i a a0 -> Indexed i a b -> Indexed i a c #

(*>) :: Indexed i a a0 -> Indexed i a b -> Indexed i a b #

(<*) :: Indexed i a a0 -> Indexed i a b -> Indexed i a a0 #

Apply (Indexed i a) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

(<.>) :: Indexed i a (a0 -> b) -> Indexed i a a0 -> Indexed i a b #

(.>) :: Indexed i a a0 -> Indexed i a b -> Indexed i a b #

(<.) :: Indexed i a a0 -> Indexed i a b -> Indexed i a a0 #

liftF2 :: (a0 -> b -> c) -> Indexed i a a0 -> Indexed i a b -> Indexed i a c #

Bind (Indexed i a) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

(>>-) :: Indexed i a a0 -> (a0 -> Indexed i a b) -> Indexed i a b #

join :: Indexed i a (Indexed i a a0) -> Indexed i a a0 #

type Rep (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

type Rep (Indexed i) = (->) i :: Type -> Type
type Corep (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

type Corep (Indexed i) = (,) i

Classes

class (Choice p, Corepresentable p, Comonad (Corep p), Traversable (Corep p), Strong p, Representable p, Monad (Rep p), MonadFix (Rep p), Distributive (Rep p), Costrong p, ArrowLoop p, ArrowApply p, ArrowChoice p, Closed p) => Conjoined p where #

This is a Profunctor that is both Corepresentable by f and Representable by g such that f is left adjoint to g. From this you can derive a lot of structure due to the preservation of limits and colimits.

Minimal complete definition

Nothing

Methods

distrib :: Functor f => p a b -> p (f a) (f b) #

Conjoined is strong enough to let us distribute every Conjoined Profunctor over every Haskell Functor. This is effectively a generalization of fmap.

conjoined :: (p ~ (->) => q (a -> b) r) -> q (p a b) r -> q (p a b) r #

This permits us to make a decision at an outermost point about whether or not we use an index.

Ideally any use of this function should be done in such a way so that you compute the same answer, but this cannot be enforced at the type level.

Instances

Instances details
Conjoined ReifiedGetter # 
Instance details

Defined in Control.Lens.Reified

Methods

distrib :: Functor f => ReifiedGetter a b -> ReifiedGetter (f a) (f b) #

conjoined :: (ReifiedGetter ~ (->) => q (a -> b) r) -> q (ReifiedGetter a b) r -> q (ReifiedGetter a b) r #

Conjoined (Indexed i) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

distrib :: Functor f => Indexed i a b -> Indexed i (f a) (f b) #

conjoined :: (Indexed i ~ (->) => q (a -> b) r) -> q (Indexed i a b) r -> q (Indexed i a b) r #

Conjoined ((->) :: Type -> Type -> Type) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

distrib :: Functor f => (a -> b) -> f a -> f b #

conjoined :: ((->) ~ (->) => q (a -> b) r) -> q (a -> b) r -> q (a -> b) r #

class Conjoined p => Indexable i p where #

This class permits overloading of function application for things that also admit a notion of a key or index.

Methods

indexed :: p a b -> i -> a -> b #

Build a function from an indexed function.

Instances

Instances details
i ~ j => Indexable i (Indexed j) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

indexed :: Indexed j a b -> i -> a -> b #

Indexable i ((->) :: Type -> Type -> Type) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

indexed :: (a -> b) -> i -> a -> b #

Indexing

newtype Indexing f a #

Applicative composition of State Int with a Functor, used by indexed.

Constructors

Indexing 

Fields

Instances

Instances details
Functor f => Functor (Indexing f) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

fmap :: (a -> b) -> Indexing f a -> Indexing f b #

(<$) :: a -> Indexing f b -> Indexing f a #

Applicative f => Applicative (Indexing f) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

pure :: a -> Indexing f a #

(<*>) :: Indexing f (a -> b) -> Indexing f a -> Indexing f b #

liftA2 :: (a -> b -> c) -> Indexing f a -> Indexing f b -> Indexing f c #

(*>) :: Indexing f a -> Indexing f b -> Indexing f b #

(<*) :: Indexing f a -> Indexing f b -> Indexing f a #

Contravariant f => Contravariant (Indexing f) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

contramap :: (a -> b) -> Indexing f b -> Indexing f a #

(>$) :: b -> Indexing f b -> Indexing f a #

Apply f => Apply (Indexing f) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

(<.>) :: Indexing f (a -> b) -> Indexing f a -> Indexing f b #

(.>) :: Indexing f a -> Indexing f b -> Indexing f b #

(<.) :: Indexing f a -> Indexing f b -> Indexing f a #

liftF2 :: (a -> b -> c) -> Indexing f a -> Indexing f b -> Indexing f c #

Semigroup (f a) => Semigroup (Indexing f a) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

(<>) :: Indexing f a -> Indexing f a -> Indexing f a #

sconcat :: NonEmpty (Indexing f a) -> Indexing f a #

stimes :: Integral b => b -> Indexing f a -> Indexing f a #

Monoid (f a) => Monoid (Indexing f a) #
>>> "cat" ^@.. (folded <> folded)
[(0,'c'),(1,'a'),(2,'t'),(0,'c'),(1,'a'),(2,'t')]
>>> "cat" ^@.. indexing (folded <> folded)
[(0,'c'),(1,'a'),(2,'t'),(3,'c'),(4,'a'),(5,'t')]
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

mempty :: Indexing f a #

mappend :: Indexing f a -> Indexing f a -> Indexing f a #

mconcat :: [Indexing f a] -> Indexing f a #

indexing :: Indexable Int p => ((a -> Indexing f b) -> s -> Indexing f t) -> p a (f b) -> s -> f t #

Transform a Traversal into an IndexedTraversal or a Fold into an IndexedFold, etc.

indexing :: Traversal s t a b -> IndexedTraversal Int s t a b
indexing :: Prism s t a b     -> IndexedTraversal Int s t a b
indexing :: Lens s t a b      -> IndexedLens Int  s t a b
indexing :: Iso s t a b       -> IndexedLens Int s t a b
indexing :: Fold s a          -> IndexedFold Int s a
indexing :: Getter s a        -> IndexedGetter Int s a
indexing :: Indexable Int p => LensLike (Indexing f) s t a b -> Over p f s t a b

64-bit Indexing

newtype Indexing64 f a #

Applicative composition of State Int64 with a Functor, used by indexed64.

Constructors

Indexing64 

Fields

Instances

Instances details
Functor f => Functor (Indexing64 f) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

fmap :: (a -> b) -> Indexing64 f a -> Indexing64 f b #

(<$) :: a -> Indexing64 f b -> Indexing64 f a #

Applicative f => Applicative (Indexing64 f) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

pure :: a -> Indexing64 f a #

(<*>) :: Indexing64 f (a -> b) -> Indexing64 f a -> Indexing64 f b #

liftA2 :: (a -> b -> c) -> Indexing64 f a -> Indexing64 f b -> Indexing64 f c #

(*>) :: Indexing64 f a -> Indexing64 f b -> Indexing64 f b #

(<*) :: Indexing64 f a -> Indexing64 f b -> Indexing64 f a #

Contravariant f => Contravariant (Indexing64 f) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

contramap :: (a -> b) -> Indexing64 f b -> Indexing64 f a #

(>$) :: b -> Indexing64 f b -> Indexing64 f a #

Apply f => Apply (Indexing64 f) # 
Instance details

Defined in Control.Lens.Internal.Indexed

Methods

(<.>) :: Indexing64 f (a -> b) -> Indexing64 f a -> Indexing64 f b #

(.>) :: Indexing64 f a -> Indexing64 f b -> Indexing64 f b #

(<.) :: Indexing64 f a -> Indexing64 f b -> Indexing64 f a #

liftF2 :: (a -> b -> c) -> Indexing64 f a -> Indexing64 f b -> Indexing64 f c #

indexing64 :: Indexable Int64 p => ((a -> Indexing64 f b) -> s -> Indexing64 f t) -> p a (f b) -> s -> f t #

Transform a Traversal into an IndexedTraversal or a Fold into an IndexedFold, etc.

This combinator is like indexing except that it handles large traversals and folds gracefully.

indexing64 :: Traversal s t a b -> IndexedTraversal Int64 s t a b
indexing64 :: Prism s t a b     -> IndexedTraversal Int64 s t a b
indexing64 :: Lens s t a b      -> IndexedLens Int64 s t a b
indexing64 :: Iso s t a b       -> IndexedLens Int64 s t a b
indexing64 :: Fold s a          -> IndexedFold Int64 s a
indexing64 :: Getter s a        -> IndexedGetter Int64 s a
indexing64 :: Indexable Int64 p => LensLike (Indexing64 f) s t a b -> Over p f s t a b

Converting to Folds

withIndex :: (Indexable i p, Functor f) => p (i, s) (f (j, t)) -> Indexed i s (f t) #

Fold a container with indices returning both the indices and the values.

The result is only valid to compose in a Traversal, if you don't edit the index as edits to the index have no effect.

>>> [10, 20, 30] ^.. ifolded . withIndex
[(0,10),(1,20),(2,30)]
>>> [10, 20, 30] ^.. ifolded . withIndex . alongside negated (re _Show)
[(0,"10"),(-1,"20"),(-2,"30")]

asIndex :: (Indexable i p, Contravariant f, Functor f) => p i (f i) -> Indexed i s (f s) #

When composed with an IndexedFold or IndexedTraversal this yields an (Indexed) Fold of the indices.