constrained-categories-0.3.0.1: Constrained clones of the category-theory type classes, using ConstraintKinds.

Copyright(c) 2016 Justus Sagemüller
LicenseGPL v3 (see COPYING)
Maintainer(@) sagemueller $ geo.uni-koeln.de
Safe HaskellTrustworthy
LanguageHaskell2010

Control.Category.Constrained.Reified

Contents

Description

GADTs that mirror the class hierarchy from Category to (at the moment) Cartesian, reifying all the available “free” composition operations.

These can be used as a “trivial base case“ for all kinds of categories: it turns out these basic operations are often not so trivial to implement, or only possible with stronger constraints than you'd like. For instance, the category of affine mappings can only be implemented directly as a category on vector spaces, because the identity mapping has zero constant offset.

By leaving the free compositions reified to runtime syntax trees, this problem can be avoided. In other applications, you may not need these cases, but can still benefit from them for optimisation (composition with id is always trivial, and so on).

Synopsis

Reified versions of the category classes

data ReCategory k α β where Source

Constructors

ReCategory :: k α β -> ReCategory k α β 
CategoryId :: Object k α => ReCategory k α α 
CategoryCompo :: Object k β => ReCategory k α β -> ReCategory k β γ -> ReCategory k α γ 

data ReCartesian k α β where Source

Constructors

ReCartesian :: k α β -> ReCartesian k α β 
CartesianId :: Object k α => ReCartesian k α α 
CartesianCompo :: Object k β => ReCartesian k α β -> ReCartesian k β γ -> ReCartesian k α γ 
CartesianSwap :: (ObjectPair k α β, ObjectPair k β α) => ReCartesian k (α, β) (β, α) 
CartesianAttachUnit :: (Object k α, UnitObject k ~ u, ObjectPair k α u) => ReCartesian k α (α, u) 
CartesianDetachUnit :: (Object k α, UnitObject k ~ u, ObjectPair k α u) => ReCartesian k (α, u) α 
CartesianRegroup :: (ObjectPair k α β, ObjectPair k β γ, ObjectPair k α (β, γ), ObjectPair k (α, β) γ) => ReCartesian k (α, (β, γ)) ((α, β), γ) 
CartesianRegroup_ :: (ObjectPair k α β, ObjectPair k β γ, ObjectPair k α (β, γ), ObjectPair k (α, β) γ) => ReCartesian k ((α, β), γ) (α, (β, γ)) 

data ReMorphism k α β where Source

Constructors

ReMorphism :: k α β -> ReMorphism k α β 
MorphismId :: Object k α => ReMorphism k α α 
MorphismCompo :: Object k β => ReMorphism k α β -> ReMorphism k β γ -> ReMorphism k α γ 
MorphismSwap :: (ObjectPair k α β, ObjectPair k β α) => ReMorphism k (α, β) (β, α) 
MorphismAttachUnit :: (Object k α, UnitObject k ~ u, ObjectPair k α u) => ReMorphism k α (α, u) 
MorphismDetachUnit :: (Object k α, UnitObject k ~ u, ObjectPair k α u) => ReMorphism k (α, u) α 
MorphismRegroup :: (ObjectPair k α β, ObjectPair k β γ, ObjectPair k α (β, γ), ObjectPair k (α, β) γ) => ReMorphism k (α, (β, γ)) ((α, β), γ) 
MorphismRegroup_ :: (ObjectPair k α β, ObjectPair k β γ, ObjectPair k α (β, γ), ObjectPair k (α, β) γ) => ReMorphism k ((α, β), γ) (α, (β, γ)) 
MorphismPar :: (ObjectPair k α γ, ObjectPair k β δ) => ReMorphism k α β -> ReMorphism k γ δ -> ReMorphism k (α, γ) (β, δ) 

data RePreArrow k α β where Source

Constructors

RePreArrow :: k α β -> RePreArrow k α β 
PreArrowId :: Object k α => RePreArrow k α α 
PreArrowCompo :: Object k β => RePreArrow k α β -> RePreArrow k β γ -> RePreArrow k α γ 
PreArrowSwap :: (ObjectPair k α β, ObjectPair k β α) => RePreArrow k (α, β) (β, α) 
PreArrowAttachUnit :: (Object k α, UnitObject k ~ u, ObjectPair k α u) => RePreArrow k α (α, u) 
PreArrowDetachUnit :: (Object k α, UnitObject k ~ u, ObjectPair k α u) => RePreArrow k (α, u) α 
PreArrowRegroup :: (ObjectPair k α β, ObjectPair k β γ, ObjectPair k α (β, γ), ObjectPair k (α, β) γ) => RePreArrow k (α, (β, γ)) ((α, β), γ) 
PreArrowRegroup_ :: (ObjectPair k α β, ObjectPair k β γ, ObjectPair k α (β, γ), ObjectPair k (α, β) γ) => RePreArrow k ((α, β), γ) (α, (β, γ)) 
PreArrowPar :: (ObjectPair k α γ, ObjectPair k β δ) => RePreArrow k α β -> RePreArrow k γ δ -> RePreArrow k (α, γ) (β, δ) 
PreArrowFanout :: (Object k α, ObjectPair k β γ) => RePreArrow k α β -> RePreArrow k α γ -> RePreArrow k α (β, γ) 
PreArrowTerminal :: Object k α => RePreArrow k α (UnitObject k) 
PreArrowFst :: ObjectPair k α β => RePreArrow k (α, β) α 
PreArrowSnd :: ObjectPair k α β => RePreArrow k (α, β) β 

data ReWellPointed k α β where Source

Constructors

ReWellPointed :: k α β -> ReWellPointed k α β 
WellPointedId :: Object k α => ReWellPointed k α α 
WellPointedCompo :: Object k β => ReWellPointed k α β -> ReWellPointed k β γ -> ReWellPointed k α γ 
WellPointedSwap :: (ObjectPair k α β, ObjectPair k β α) => ReWellPointed k (α, β) (β, α) 
WellPointedAttachUnit :: (Object k α, UnitObject k ~ u, ObjectPair k α u) => ReWellPointed k α (α, u) 
WellPointedDetachUnit :: (Object k α, UnitObject k ~ u, ObjectPair k α u) => ReWellPointed k (α, u) α 
WellPointedRegroup :: (ObjectPair k α β, ObjectPair k β γ, ObjectPair k α (β, γ), ObjectPair k (α, β) γ) => ReWellPointed k (α, (β, γ)) ((α, β), γ) 
WellPointedRegroup_ :: (ObjectPair k α β, ObjectPair k β γ, ObjectPair k α (β, γ), ObjectPair k (α, β) γ) => ReWellPointed k ((α, β), γ) (α, (β, γ)) 
WellPointedPar :: (ObjectPair k α γ, ObjectPair k β δ) => ReWellPointed k α β -> ReWellPointed k γ δ -> ReWellPointed k (α, γ) (β, δ) 
WellPointedFanout :: (Object k α, ObjectPair k β γ) => ReWellPointed k α β -> ReWellPointed k α γ -> ReWellPointed k α (β, γ) 
WellPointedTerminal :: Object k α => ReWellPointed k α (UnitObject k) 
WellPointedFst :: ObjectPair k α β => ReWellPointed k (α, β) α 
WellPointedSnd :: ObjectPair k α β => ReWellPointed k (α, β) β 
WellPointedConst :: (Object k ν, ObjectPoint k α) => α -> ReWellPointed k ν α