License	BSD-style (see the file LICENSE)
Maintainer	sjoerd@w3future.com
Stability	experimental
Portability	non-portable
Safe Haskell	Safe
Language	Haskell2010

Data.Category

Contents

Category
Opposite category

Description

Synopsis

class Category k where
- src :: k a b -> Obj k a
- tgt :: k a b -> Obj k b
- (.) :: k b c -> k a b -> k a c
type Obj k a = k a a
newtype Op k a b = Op {
- unOp :: k b a
}

Category

class Category k where Source #

An instance of Category k declares the arrow k as a category.

Methods

src :: k a b -> Obj k a Source #

tgt :: k a b -> Obj k b Source #

(.) :: k b c -> k a b -> k a c infixr 8 Source #

Instances

Category Cat Source #	`Cat` is the category with categories as objects and funtors as arrows.
Instance details Defined in Data.Category.Functor Methods src :: Cat a b -> Obj Cat a Source # tgt :: Cat a b -> Obj Cat b Source # (.) :: Cat b c -> Cat a b -> Cat a c Source #
Category AdjArrow Source #	The category with categories as objects and adjunctions as arrows.
Instance details Defined in Data.Category.Adjunction Methods src :: AdjArrow a b -> Obj AdjArrow a Source # tgt :: AdjArrow a b -> Obj AdjArrow b Source # (.) :: AdjArrow b c -> AdjArrow a b -> AdjArrow a c Source #
Category Unit Source #	`Unit` is the category with one object.
Instance details Defined in Data.Category.Unit Methods src :: Unit a b -> Obj Unit a Source # tgt :: Unit a b -> Obj Unit b Source # (.) :: Unit b c -> Unit a b -> Unit a c Source #
Category Void Source #	`Void` is the category with no objects.
Instance details Defined in Data.Category.Void Methods src :: Void a b -> Obj Void a Source # tgt :: Void a b -> Obj Void b Source # (.) :: Void b c -> Void a b -> Void a c Source #
Category Simplex Source #	The (augmented) simplex category is the category of finite ordinals and order preserving maps.
Instance details Defined in Data.Category.Simplex Methods src :: Simplex a b -> Obj Simplex a Source # tgt :: Simplex a b -> Obj Simplex b Source # (.) :: Simplex b c -> Simplex a b -> Simplex a c Source #
Category Cube Source #
Instance details Defined in Data.Category.Cube Methods src :: Cube a b -> Obj Cube a Source # tgt :: Cube a b -> Obj Cube b Source # (.) :: Cube b c -> Cube a b -> Cube a c Source #
Category Boolean Source #	`Boolean` is the category with true and false as objects, and an arrow from false to true.
Instance details Defined in Data.Category.Boolean Methods src :: Boolean a b -> Obj Boolean a Source # tgt :: Boolean a b -> Obj Boolean b Source # (.) :: Boolean b c -> Boolean a b -> Boolean a c Source #
Category k => Category (Op k) Source #	`Op k` is opposite category of the category `k`.
Instance details Defined in Data.Category Methods src :: Op k a b -> Obj (Op k) a Source # tgt :: Op k a b -> Obj (Op k) b Source # (.) :: Op k b c -> Op k a b -> Op k a c Source #
(Functor f, Dom f ~ (Op c :**: d), Cod f ~ ((->) :: Type -> Type -> Type), Category c, Category d) => Category (Cograph f) Source #	The cograph of the profunctor `f`.
Instance details Defined in Data.Category.Coproduct Methods src :: Cograph f a b -> Obj (Cograph f) a Source # tgt :: Cograph f a b -> Obj (Cograph f) b Source # (.) :: Cograph f b c -> Cograph f a b -> Cograph f a c Source #
Category (Kleisli m) Source #	The category of Kleisli arrows.
Instance details Defined in Data.Category.Kleisli Methods src :: Kleisli m a b -> Obj (Kleisli m) a Source # tgt :: Kleisli m a b -> Obj (Kleisli m) b Source # (.) :: Kleisli m b c -> Kleisli m a b -> Kleisli m a c Source #
Category (f (Fix f)) => Category (Fix f) Source #	`Fix f` is the fixed point category for a category combinator `f`.
Instance details Defined in Data.Category.Fix Methods src :: Fix f a b -> Obj (Fix f) a Source # tgt :: Fix f a b -> Obj (Fix f) b Source # (.) :: Fix f b c -> Fix f a b -> Fix f a c Source #
ECategory k => Category (Underlying k) Source #	The underlying category of an enriched category
Instance details Defined in Data.Category.Enriched Methods src :: Underlying k a b -> Obj (Underlying k) a Source # tgt :: Underlying k a b -> Obj (Underlying k) b Source # (.) :: Underlying k b c -> Underlying k a b -> Underlying k a c Source #
Category ((->) :: Type -> Type -> Type) Source #	The category with Haskell types as objects and Haskell functions as arrows.
Instance details Defined in Data.Category Methods src :: (a -> b) -> Obj (->) a Source # tgt :: (a -> b) -> Obj (->) b Source # (.) :: (b -> c) -> (a -> b) -> a -> c Source #
(Category c1, Category c2) => Category (c1 :**: c2) Source #	The product category of categories `c1` and `c2`.
Instance details Defined in Data.Category.Product Methods src :: (c1 :: c2) a b -> Obj (c1 :: c2) a Source # tgt :: (c1 :: c2) a b -> Obj (c1 :: c2) b Source # (.) :: (c1 :: c2) b c -> (c1 :: c2) a b -> (c1 :**: c2) a c Source #
Category d => Category (Nat c d) Source #	Functor category D^C. Objects of D^C are functors from C to D. Arrows of D^C are natural transformations.
Instance details Defined in Data.Category.NaturalTransformation Methods src :: Nat c d a b -> Obj (Nat c d) a Source # tgt :: Nat c d a b -> Obj (Nat c d) b Source # (.) :: Nat c d b c0 -> Nat c d a b -> Nat c d a c0 Source #
(Category c1, Category c2) => Category (c1 :>>: c2) Source #
Instance details Defined in Data.Category.Coproduct Methods src :: (c1 :>>: c2) a b -> Obj (c1 :>>: c2) a Source # tgt :: (c1 :>>: c2) a b -> Obj (c1 :>>: c2) b Source # (.) :: (c1 :>>: c2) b c -> (c1 :>>: c2) a b -> (c1 :>>: c2) a c Source #
(Category c1, Category c2) => Category (c1 :++: c2) Source #	The coproduct category of categories `c1` and `c2`.
Instance details Defined in Data.Category.Coproduct Methods src :: (c1 :++: c2) a b -> Obj (c1 :++: c2) a Source # tgt :: (c1 :++: c2) a b -> Obj (c1 :++: c2) b Source # (.) :: (c1 :++: c2) b c -> (c1 :++: c2) a b -> (c1 :++: c2) a c Source #
Category (MonoidAsCategory f m) Source #	A monoid as a category with one object.
Instance details Defined in Data.Category.Monoidal Methods src :: MonoidAsCategory f m a b -> Obj (MonoidAsCategory f m) a Source # tgt :: MonoidAsCategory f m a b -> Obj (MonoidAsCategory f m) b Source # (.) :: MonoidAsCategory f m b c -> MonoidAsCategory f m a b -> MonoidAsCategory f m a c Source #
Category (Dialg f g) Source #	The category of (F,G)-dialgebras.
Instance details Defined in Data.Category.Dialg Methods src :: Dialg f g a b -> Obj (Dialg f g) a Source # tgt :: Dialg f g a b -> Obj (Dialg f g) b Source # (.) :: Dialg f g b c -> Dialg f g a b -> Dialg f g a c Source #
(Category (Dom t), Category (Dom s)) => Category (t :/\: s) Source #	The comma category T \downarrow S
Instance details Defined in Data.Category.Comma Methods src :: (t :/\: s) a b -> Obj (t :/\: s) a Source # tgt :: (t :/\: s) a b -> Obj (t :/\: s) b Source # (.) :: (t :/\: s) b c -> (t :/\: s) a b -> (t :/\: s) a c Source #

type Obj k a = k a a Source #

Whenever objects are required at value level, they are represented by their identity arrows.

Opposite category

newtype Op k a b Source #

Constructors

Op
Fields unOp :: k b a

Instances

Category k => Category (Op k) Source #	`Op k` is opposite category of the category `k`.
Instance details Defined in Data.Category Methods src :: Op k a b -> Obj (Op k) a Source # tgt :: Op k a b -> Obj (Op k) b Source # (.) :: Op k b c -> Op k a b -> Op k a c Source #
HasBinaryProducts k => HasBinaryCoproducts (Op k) Source #	Binary products are the dual of binary coproducts.
Instance details Defined in Data.Category.Limit Associated Types type BinaryCoproduct (Op k) x y :: Type Source # Methods inj1 :: Obj (Op k) x -> Obj (Op k) y -> Op k x (BinaryCoproduct (Op k) x y) Source # inj2 :: Obj (Op k) x -> Obj (Op k) y -> Op k y (BinaryCoproduct (Op k) x y) Source # (\|\|\|) :: Op k x a -> Op k y a -> Op k (BinaryCoproduct (Op k) x y) a Source # (+++) :: Op k a1 b1 -> Op k a2 b2 -> Op k (BinaryCoproduct (Op k) a1 a2) (BinaryCoproduct (Op k) b1 b2) Source #
HasBinaryCoproducts k => HasBinaryProducts (Op k) Source #	Binary products are the dual of binary coproducts.
Instance details Defined in Data.Category.Limit Associated Types type BinaryProduct (Op k) x y :: Type Source # Methods proj1 :: Obj (Op k) x -> Obj (Op k) y -> Op k (BinaryProduct (Op k) x y) x Source # proj2 :: Obj (Op k) x -> Obj (Op k) y -> Op k (BinaryProduct (Op k) x y) y Source # (&&&) :: Op k a x -> Op k a y -> Op k a (BinaryProduct (Op k) x y) Source # (***) :: Op k a1 b1 -> Op k a2 b2 -> Op k (BinaryProduct (Op k) a1 a2) (BinaryProduct (Op k) b1 b2) Source #
HasTerminalObject k => HasInitialObject (Op k) Source #	Terminal objects are the dual of initial objects.
Instance details Defined in Data.Category.Limit Associated Types type InitialObject (Op k) :: Type Source # Methods initialObject :: Obj (Op k) (InitialObject (Op k)) Source # initialize :: Obj (Op k) a -> Op k (InitialObject (Op k)) a Source #
HasInitialObject k => HasTerminalObject (Op k) Source #	Terminal objects are the dual of initial objects.
Instance details Defined in Data.Category.Limit Associated Types type TerminalObject (Op k) :: Type Source # Methods terminalObject :: Obj (Op k) (TerminalObject (Op k)) Source # terminate :: Obj (Op k) a -> Op k a (TerminalObject (Op k)) Source #
Category k => CartesianClosed (Presheaves k) Source #	The category of presheaves on a category `C` is cartesian closed for any `C`.
Instance details Defined in Data.Category.CartesianClosed Associated Types type Exponential (Presheaves k) y z :: Type Source # Methods apply :: Obj (Presheaves k) y -> Obj (Presheaves k) z -> Presheaves k (BinaryProduct (Presheaves k) (Exponential (Presheaves k) y z) y) z Source # tuple :: Obj (Presheaves k) y -> Obj (Presheaves k) z -> Presheaves k z (Exponential (Presheaves k) y (BinaryProduct (Presheaves k) z y)) Source # (^^^) :: Presheaves k z1 z2 -> Presheaves k y2 y1 -> Presheaves k (Exponential (Presheaves k) y1 z1) (Exponential (Presheaves k) y2 z2) Source #
type InitialObject (Op k) Source #
Instance details Defined in Data.Category.Limit type InitialObject (Op k) = TerminalObject k
type TerminalObject (Op k) Source #
Instance details Defined in Data.Category.Limit type TerminalObject (Op k) = InitialObject k
type BinaryCoproduct (Op k) x y Source #
Instance details Defined in Data.Category.Limit type BinaryCoproduct (Op k) x y = BinaryProduct k x y
type BinaryProduct (Op k) x y Source #
Instance details Defined in Data.Category.Limit type BinaryProduct (Op k) x y = BinaryCoproduct k x y
type Exponential (Presheaves k) y z Source #
Instance details Defined in Data.Category.CartesianClosed type Exponential (Presheaves k) y z = PShExponential k y z