Modulesop-extras-0.4.1.1Haskell2010

Data.SOP.Counting

Type-level counting

Intended for unqualified import.

2 types
16 values

Packagesop-extras-0.4.1.1
Exports20
LanguageHaskell2010
LicenceApache-2.0
SourceCounting.hs

datadata AtMost (xs :: [Type]) a where

At most one value for each type level index

Constructors

AtMostNil :: AtMost xs a
AtMostCons :: !a -> !AtMost xs1 a -> AtMost (x ': xs1) a

Instances5Functor, Foldable, Traversable, Eq, Show

Functor (AtMost xs)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting
Foldable (AtMost xs)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting
Traversable (AtMost xs)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting
Eq a => Eq (AtMost xs a)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting
Show a => Show (AtMost xs a)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting

newtypenewtype Exactly (xs :: [Type]) a

Constructors

Exactly
- getExactly :: NP (K a) xs

Instances5Functor, Foldable, Traversable, Eq, Show

Functor (Exactly xs)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting
Foldable (Exactly xs)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting
Traversable (Exactly xs)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting
Eq a => Eq (Exactly xs a)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting
Show a => Show (Exactly xs a)Defined in sop-extras-0.4.1.1 · Data.SOP.Counting

patternpattern ExactlyNil :: () => xs ~ '[] => Exactly xs a

patternpattern ExactlyCons :: () => xs' ~ (x ': xs) => a -> Exactly xs a -> Exactly xs' a

Working with Exactly

9 declarations

valueexactlyHead :: Exactly (x ': xs) a -> a

Analogue of head

valueexactlyOne :: a -> Exactly '[x] a

Singleton

valueexactlyReplicate

:: Word
-> a
-> forall (xs :: [Type]). Exactly xs a -> r
-> r

Analogue of replicate

In CPS style because the xs type parameter is not statically known.

valueexactlyTail :: Exactly (x ': xs) a -> Exactly xs a

Analogue of tail

valueexactlyTwo :: a -> a -> Exactly '[x, y] a

From a pair

valueexactlyWeaken :: Exactly xs a -> AtMost xs a

valueexactlyWeakenNonEmpty :: Exactly (x ': xs) a -> NonEmpty (x ': xs) a

valueexactlyZip :: Exactly xs a -> Exactly xs b -> Exactly xs (a, b)

Analogue of zip

valueexactlyZipFoldable :: Foldable t => Exactly xs a -> t b -> AtMost xs (a, b)

Analogue of zip where the length of second argument is unknown

Working with AtMost

7 declarations

valueatMostFromNonEmpty :: NonEmpty xs a -> AtMost xs a

valueatMostHead :: AtMost xs a -> Maybe a

Analogue of head

valueatMostInit :: AtMost xs a -> Maybe (AtMost xs a, a)

Analogue of init

For simplicity we don't shrink the type-level index.

valueatMostLast :: AtMost xs a -> Maybe a

Analogue of last

valueatMostNonEmpty :: AtMost (x ': xs) a -> Maybe (NonEmpty (x ': xs) a)

valueatMostOne :: a -> AtMost (x ': xs) a

Singleton

valueatMostZipFoldable :: Foldable t => AtMost xs a -> t b -> AtMost xs (a, b)