Safe Haskell	Safe-Inferred
Language	GHC2021

Fold.Nonempty

Contents

Type
Run
Examples
Conversion
Utilities

Synopsis

data NonemptyFold a b = forall x.NonemptyFold {
- initial :: a -> x
- step :: x -> a -> x
- extract :: x -> b
}
run :: NonemptyFold a b -> NonEmpty a -> b
magma :: (a -> a -> a) -> NonemptyFold a a
semigroup :: Semigroup a => NonemptyFold a a
monoid :: Monoid a => NonemptyFold a a
first :: NonemptyFold a a
last :: NonemptyFold a a
maximum :: Ord a => NonemptyFold a a
minimum :: Ord a => NonemptyFold a a
maximumBy :: (a -> a -> Ordering) -> NonemptyFold a a
minimumBy :: (a -> a -> Ordering) -> NonemptyFold a a
length :: NonemptyFold a Natural
and :: NonemptyFold Bool Bool
or :: NonemptyFold Bool Bool
all :: (a -> Bool) -> NonemptyFold a Bool
any :: (a -> Bool) -> NonemptyFold a Bool
sum :: Num a => NonemptyFold a a
product :: Num a => NonemptyFold a a
mean :: Fractional a => NonemptyFold a a
variance :: Fractional a => NonemptyFold a a
standardDeviation :: Floating a => NonemptyFold a a
element :: Eq a => a -> NonemptyFold a Bool
notElement :: Eq a => a -> NonemptyFold a Bool
find :: (a -> Bool) -> NonemptyFold a (Maybe a)
lookup :: Eq a => a -> NonemptyFold (a, b) (Maybe b)
index :: Natural -> NonemptyFold a (Maybe a)
findIndex :: (a -> Bool) -> NonemptyFold a (Maybe Natural)
elementIndex :: Eq a => a -> NonemptyFold a (Maybe Natural)
list :: NonemptyFold a (NonEmpty a)
reverseList :: NonemptyFold a (NonEmpty a)
fold :: Fold a b -> NonemptyFold a b
effectfulFold :: EffectfulFold Identity a b -> NonemptyFold a b
shortcutFold :: ShortcutFold a b -> NonemptyFold a b
shortcutNonemptyFold :: ShortcutNonemptyFold a b -> NonemptyFold a b
duplicate :: NonemptyFold a b -> NonemptyFold a (Fold a b)
repeatedly :: forall x xs result. (forall b. NonemptyFold x b -> xs -> b) -> NonemptyFold x result -> NonemptyFold xs result
premap :: (a -> b) -> NonemptyFold b r -> NonemptyFold a r
nest :: Applicative f => NonemptyFold a b -> NonemptyFold (f a) (f b)

Type

data NonemptyFold a b Source #

Processes at least one input of type a and results in a value of type b

Constructors

forall x. NonemptyFold
Fields initial :: a -> x step :: x -> a -> x extract :: x -> b

Instances

Instances details

Applicative (NonemptyFold a) Source #
Instance details Defined in Fold.Nonempty.Type Methods pure :: a0 -> NonemptyFold a a0 # (<>) :: NonemptyFold a (a0 -> b) -> NonemptyFold a a0 -> NonemptyFold a b # liftA2 :: (a0 -> b -> c) -> NonemptyFold a a0 -> NonemptyFold a b -> NonemptyFold a c # (>) :: NonemptyFold a a0 -> NonemptyFold a b -> NonemptyFold a b # (<*) :: NonemptyFold a a0 -> NonemptyFold a b -> NonemptyFold a a0 #
Functor (NonemptyFold a) Source #
Instance details Defined in Fold.Nonempty.Type Methods fmap :: (a0 -> b) -> NonemptyFold a a0 -> NonemptyFold a b # (<$) :: a0 -> NonemptyFold a b -> NonemptyFold a a0 #
Monoid b => Monoid (NonemptyFold a b) Source #
Instance details Defined in Fold.Nonempty.Type Methods mempty :: NonemptyFold a b # mappend :: NonemptyFold a b -> NonemptyFold a b -> NonemptyFold a b # mconcat :: [NonemptyFold a b] -> NonemptyFold a b #
Semigroup b => Semigroup (NonemptyFold a b) Source #
Instance details Defined in Fold.Nonempty.Type Methods (<>) :: NonemptyFold a b -> NonemptyFold a b -> NonemptyFold a b # sconcat :: NonEmpty (NonemptyFold a b) -> NonemptyFold a b # stimes :: Integral b0 => b0 -> NonemptyFold a b -> NonemptyFold a b #

Run

run :: NonemptyFold a b -> NonEmpty a -> b Source #

Fold a nonempty listlike container to a single summary result

Examples

General

magma :: (a -> a -> a) -> NonemptyFold a a Source #

Start with the first input, append each new input on the right with the given function

semigroup :: Semigroup a => NonemptyFold a a Source #

Append each new input on the right with (<>)

monoid :: Monoid a => NonemptyFold a a Source #

Start with mempty, append each input on the right with (<>)

Endpoints

first :: NonemptyFold a a Source #

The first input

last :: NonemptyFold a a Source #

The last input

Extrema

maximum :: Ord a => NonemptyFold a a Source #

The greatest input

minimum :: Ord a => NonemptyFold a a Source #

The least input

maximumBy :: (a -> a -> Ordering) -> NonemptyFold a a Source #

The greatest input with respect to the given comparison function

minimumBy :: (a -> a -> Ordering) -> NonemptyFold a a Source #

The least input with respect to the given comparison function

Length

length :: NonemptyFold a Natural Source #

The number of inputs

Boolean

and :: NonemptyFold Bool Bool Source #

True if all inputs are True

or :: NonemptyFold Bool Bool Source #

True if any input is True

all :: (a -> Bool) -> NonemptyFold a Bool Source #

True if all inputs satisfy the predicate

any :: (a -> Bool) -> NonemptyFold a Bool Source #

True if any input satisfies the predicate

Numeric

sum :: Num a => NonemptyFold a a Source #

Adds the inputs

product :: Num a => NonemptyFold a a Source #

Multiplies the inputs

mean :: Fractional a => NonemptyFold a a Source #

Numerically stable arithmetic mean of the inputs

variance :: Fractional a => NonemptyFold a a Source #

Numerically stable (population) variance over the inputs

standardDeviation :: Floating a => NonemptyFold a a Source #

Numerically stable (population) standard deviation over the inputs

Search

element :: Eq a => a -> NonemptyFold a Bool Source #

True if any input is equal to the given value

notElement :: Eq a => a -> NonemptyFold a Bool Source #

False if any input is equal to the given value

find :: (a -> Bool) -> NonemptyFold a (Maybe a) Source #

The first input that satisfies the predicate, if any

lookup :: Eq a => a -> NonemptyFold (a, b) (Maybe b) Source #

The b from the first tuple where a equals the given value, if any

Index

index :: Natural -> NonemptyFold a (Maybe a) Source #

The nth input, where n=0 is the first input, if the index is in bounds

findIndex :: (a -> Bool) -> NonemptyFold a (Maybe Natural) Source #

The index of the first input that satisfies the predicate, if any

elementIndex :: Eq a => a -> NonemptyFold a (Maybe Natural) Source #

The index of the first input that matches the given value, if any

List

list :: NonemptyFold a (NonEmpty a) Source #

All the inputs

reverseList :: NonemptyFold a (NonEmpty a) Source #

All the inputs in reverse order

Conversion

fold :: Fold a b -> NonemptyFold a b Source #

Turn a regular fold that allows empty input into a fold that requires at least one input

effectfulFold :: EffectfulFold Identity a b -> NonemptyFold a b Source #

Turn an effectful fold into a pure fold that requires at least one input

shortcutFold :: ShortcutFold a b -> NonemptyFold a b Source #

shortcutNonemptyFold :: ShortcutNonemptyFold a b -> NonemptyFold a b Source #

Utilities

duplicate :: NonemptyFold a b -> NonemptyFold a (Fold a b) Source #

Allows to continue feeding a fold even after passing it to a function that closes it

repeatedly Source #

Arguments

:: forall x xs result. (forall b. NonemptyFold x b -> xs -> b)	A witness to the fact that `xs` is a nonempty list of `x`
-> NonemptyFold x result
-> NonemptyFold xs result

Convert a nonempty fold for a single item (x) into a nonempty fold for nonempty lists of items (xs)

premap :: (a -> b) -> NonemptyFold b r -> NonemptyFold a r Source #

Applies a function to each input before processing

nest :: Applicative f => NonemptyFold a b -> NonemptyFold (f a) (f b) Source #

Nest a fold in an applicative