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liftA1 :: forall f a b. Applicative f => (a -> b) -> f a -> f b

liftA1 provides a default implementation of (<$>) for any Applicative functor, without using (<$>) as provided by the Functor-Applicative superclass relationship.

liftA1 can therefore be used to write Functor instances as follows:

instance functorF :: Functor F where
  map = liftA1

liftM1 :: forall m a b. Monad m => (a -> b) -> m a -> m b

liftM1 provides a default implementation of (<$>) for any Monad, without using (<$>) as provided by the Functor-Monad superclass relationship.

liftM1 can therefore be used to write Functor instances as follows:

instance functorF :: Functor F where
  map = liftM1

map :: forall f a b. Functor f => (a -> b) -> f a -> f b

mapDefault :: forall i f a b. FunctorWithIndex i f => (a -> b) -> f a -> f b

A default implementation of Functor's map in terms of mapWithIndex

cmap :: forall f a b. Contravariant f => (b -> a) -> f a -> f b

censor :: forall w m a. MonadWriter w m => (w -> w) -> m a -> m a

Modify the final accumulator value by applying a function.

local :: forall e w a. ComonadEnv e w => (e -> e) -> w a -> w a

local :: forall m r a. MonadReader r m => (r -> r) -> m a -> m a

seeks :: forall s a w. ComonadStore s w => (s -> s) -> w a -> w a

Reposition the focus at the specified position, which depends on the current position.

applyFirst :: forall a b f. Apply f => f a -> f b -> f a

Combine two effectful actions, keeping only the result of the first.

all :: forall a b f. Foldable f => HeytingAlgebra b => (a -> b) -> f a -> b

all f is the same as and <<< map f; map a function over the structure, and then get the conjunction of the results.

any :: forall a b f. Foldable f => HeytingAlgebra b => (a -> b) -> f a -> b

any f is the same as or <<< map f; map a function over the structure, and then get the disjunction of the results.

foldMap :: forall f a m. Foldable f => Monoid m => (a -> m) -> f a -> m

foldMap1 :: forall t a m. Foldable1 t => Semigroup m => (a -> m) -> t a -> m

foldMap1Default :: forall t m a. Warn (Text "\'foldMap1Default\' is deprecated, use \'foldMap1DefaultL\' instead") => Foldable1 t => Functor t => Semigroup m => (a -> m) -> t a -> m

Deprecated previous name of foldMap1DefaultL.

foldMap1DefaultL :: forall t m a. Foldable1 t => Functor t => Semigroup m => (a -> m) -> t a -> m

A default implementation of foldMap1 using foldl1.

Note: when defining a Foldable1 instance, this function is unsafe to use in combination with foldl1Default.

foldMap1DefaultR :: forall t m a. Foldable1 t => Functor t => Semigroup m => (a -> m) -> t a -> m

A default implementation of foldMap1 using foldr1.

Note: when defining a Foldable1 instance, this function is unsafe to use in combination with foldr1Default.

foldMapDefault :: forall i f a m. FoldableWithIndex i f => Monoid m => (a -> m) -> f a -> m

A default implementation of foldMap using foldMapWithIndex

foldMapDefaultL :: forall f a m. Foldable f => Monoid m => (a -> m) -> f a -> m

A default implementation of foldMap using foldl.

Note: when defining a Foldable instance, this function is unsafe to use in combination with foldlDefault.

foldMapDefaultR :: forall f a m. Foldable f => Monoid m => (a -> m) -> f a -> m

A default implementation of foldMap using foldr.

Note: when defining a Foldable instance, this function is unsafe to use in combination with foldrDefault.

tracks :: forall w a t. ComonadTraced t w => (a -> t) -> w a -> a

Extracts a value at a relative position which depends on the current value.

asks :: forall e1 e2 w a. ComonadAsk e1 w => (e1 -> e2) -> w a -> e2

Get a value which depends on the environment.

alt :: forall f a. Alt f => f a -> f a -> f a

choose :: forall m a. MonadGen m => m a -> m a -> m a

Creates a generator that outputs a value chosen from one of two existing existing generators with even probability.

applySecond :: forall a b f. Apply f => f a -> f b -> f b

Combine two effectful actions, keeping only the result of the second.

peeks :: forall s a w. ComonadStore s w => (s -> s) -> w a -> a

Extract a value from a position which depends on the current position.

voidRight :: forall f a b. Functor f => a -> f b -> f a

Ignore the return value of a computation, using the specified return value instead.

seek :: forall s a w. ComonadStore s w => s -> w a -> w a

Reposition the focus at the specified position.

apply :: forall a b. (a -> b) -> a -> b

Applies a function to an argument. This is primarily used as the operator ($) which allows parentheses to be omitted in some cases, or as a natural way to apply a chain of composed functions to a value.

un :: forall t a. Newtype t a => (a -> t) -> t -> a

Given a constructor for a Newtype, this returns the appropriate unwrap function.

voidLeft :: forall f a b. Functor f => f a -> b -> f b

A version of voidRight with its arguments flipped.

duplicate :: forall a w. Extend w => w a -> w (w a)

Duplicate a comonadic context.

duplicate is dual to Control.Bind.join.

intercalate :: forall f m. Foldable f => Monoid m => m -> f m -> m

Fold a data structure, accumulating values in some Monoid, combining adjacent elements using the specified separator.

For example:

> intercalate ", " ["Lorem", "ipsum", "dolor"]
= "Lorem, ipsum, dolor"

> intercalate "*" ["a", "b", "c"]
= "a*b*c"

> intercalate [1] [[2, 3], [4, 5], [6, 7]]
= [2, 3, 1, 4, 5, 1, 6, 7]

intercalate :: forall f m. Foldable1 f => Semigroup m => m -> f m -> m

Fold a data structure using a Semigroup instance, combining adjacent elements using the specified separator.

surround :: forall f m. Foldable f => Semigroup m => m -> f m -> m

fold but with each element surrounded by some fixed value.

For example:

> surround "*" []
= "*"

> surround "*" ["1"]
= "*1*"

> surround "*" ["1", "2"]
= "*1*2*"

> surround "*" ["1", "2", "3"]
= "*1*2*3*"

unfoldable :: forall m f a. MonadRec m => MonadGen m => Unfoldable f => m a -> m (f a)

Creates a generator that produces unfoldable structures based on an existing generator for the elements.

The size of the unfoldable will be determined by the current size state for the generator. To generate an unfoldable structure of a particular size, use the resize function from the MonadGen class first.

enumFromTo :: forall a u. Enum a => Unfoldable1 u => a -> a -> u a

Returns a contiguous sequence of elements from the first value to the second value (inclusive).

enumFromTo 0 3 = [0, 1, 2, 3]
enumFromTo 'c' 'a' = ['c', 'b', 'a']

The example shows Array return values, but the result can be any type with an Unfoldable1 instance.

asks :: forall r m a. MonadAsk r m => (r -> a) -> m a

Projects a value from the global context in a MonadAsk.

gets :: forall s m a. MonadState s m => (s -> a) -> m a

Get a value which depends on the current state.

peek :: forall s w a. ComonadStore s w => s -> w a -> a

track :: forall t w a. ComonadTraced t w => t -> w a -> a

unwrapCofree :: forall f w a. ComonadCofree f w => w a -> f (w a)

fix :: forall l. Lazy l => (l -> l) -> l

fix defines a value as the fixed point of a function.

The Lazy instance allows us to generate the result lazily.

modify :: forall s m. MonadState s m => (s -> s) -> m s

Modify the state by applying a function to the current state. The returned value is the new state value.

add :: forall a. Semiring a => a -> a -> a

append :: forall a. Semigroup a => a -> a -> a

conj :: forall a. HeytingAlgebra a => a -> a -> a

const :: forall a b. a -> b -> a

Returns its first argument and ignores its second.

const 1 "hello" = 1

It can also be thought of as creating a function that ignores its argument:

const 1 = \_ -> 1

disj :: forall a. HeytingAlgebra a => a -> a -> a

div :: forall a. EuclideanRing a => a -> a -> a