Data.Thrist

Types

data Thrist :: (k -> k -> *) -> k -> k -> * where

A type-threaded list of binary polymorphic types.

Constructors

Nil :: Thrist arr a a

Cons :: (a `arr` b) -> Thrist arr b c -> Thrist arr a c

Instances

Category (Thrist arr :: k -> k -> Type)

Defined in Data.Thrist

Methods

id :: Thrist arr a a

(.) :: Thrist arr b c -> Thrist arr a b -> Thrist arr a c

Arrow arr => Arrow (Thrist arr)

Defined in Data.Thrist

Methods

arr :: (b -> c) -> Thrist arr b c

first :: Thrist arr b c -> Thrist arr (b, d) (c, d)

second :: Thrist arr b c -> Thrist arr (d, b) (d, c)

(***) :: Thrist arr b c -> Thrist arr b' c' -> Thrist arr (b, b') (c, c')

(&&&) :: Thrist arr b c -> Thrist arr b c' -> Thrist arr b (c, c')

Semigroup (Thrist arr a a)

Defined in Data.Thrist

Methods

(<>) :: Thrist arr a a -> Thrist arr a a -> Thrist arr a a

sconcat :: NonEmpty (Thrist arr a a) -> Thrist arr a a

stimes :: Integral b => b -> Thrist arr a a -> Thrist arr a a

Monoid (Thrist arr a a)

Defined in Data.Thrist

Methods

mempty :: Thrist arr a a

mappend :: Thrist arr a a -> Thrist arr a a -> Thrist arr a a

mconcat :: [Thrist arr a a] -> Thrist arr a a

newtype Flipped m a b

A newtype wrapper, defined for convenience, that "swaps" the two type variables of a binary type. Can be used to reverse a Thrist using foldlThrist. See examples.

Constructors

Flipped

Fields

• unflip :: m b a

Fold and map functions

mapThrist :: (forall i j. (i `brr` j) -> i `arr` j) -> Thrist brr a b -> Thrist arr a b

Equivalent to map for thrists. Takes a function from one binary type to another and applies it to each thrist element. For example this could convert a thrist of (a,b) into a thrist of Either a b:

foldrThrist :: (forall i j. (i `arr` j) -> (j `brr` c) -> i `brr` c) -> (b `brr` c) -> Thrist arr a b -> a `brr` c

Equivalent to foldr for thrists. Takes a combining function, a value to replace Nil, and a thrist, returning some new binary type.

foldlThrist :: (forall j k. (a `brr` j) -> (j `arr` k) -> a `brr` k) -> (a `brr` b) -> Thrist arr b c -> a `brr` c

Equivalent to foldl for Thrists.

foldr1Thrist :: (forall i j k. (i `arr` j) -> (j `arr` k) -> i `arr` k) -> Thrist arr a b -> a `arr` b

Equivalent to foldr1 for Thrists.

foldl1Thrist :: (forall i j k. (i `arr` j) -> (j `arr` k) -> i `arr` k) -> Thrist arr a b -> a `arr` b

Equivalent to foldl1 for Thrists.

Monadic functions

mapMThrist :: Monad m => (forall i j. (i `brr` j) -> m (i `arr` j)) -> Thrist brr a b -> m (Thrist arr a b)

Equivalent to mapM on Thrists.

foldMThrist :: Monad m => (forall j k. (a `brr` j) -> (j `arr` k) -> m (a `brr` k)) -> (a `brr` b) -> Thrist arr b c -> m (a `brr` c)

Equivalent to foldM on Thrists.

Other list-like functions

appendThrist :: Thrist arr a b -> Thrist arr b c -> Thrist arr a c

Equivalent to (++) for thrists.

nullThrist :: Thrist arr a b -> Bool

Returns True when the Thrist is Nil.

lengthThrist :: Thrist arr a b -> Int

Returns the length of the Thrist.