Data.Semigroup

Documentation

class Semigroup a where

Methods

(<>) :: a -> a -> a

sconcat :: NonEmpty a -> a

Instances

Semigroup ()

Semigroup All

Semigroup Any

Semigroup IntSet

Semigroup [a]

Semigroup a => Semigroup (Dual a)

Semigroup (Endo a)

Num a => Semigroup (Sum a)

Num a => Semigroup (Product a)

Semigroup (First a)

Semigroup (Last a)

Semigroup a => Semigroup (Maybe a)

Semigroup (Seq a)

Semigroup (IntMap v)

Ord a => Semigroup (Set a)

Semigroup (NonEmpty a)

Semigroup a => Semigroup (Option a)

Monoid m => Semigroup (WrappedMonoid m)

Semigroup (Last a)

Semigroup (First a)

Ord a => Semigroup (Max a)

Ord a => Semigroup (Min a)

Semigroup b => Semigroup (a -> b)

Semigroup (Either a b)

(Semigroup a, Semigroup b) => Semigroup (a, b)

Ord k => Semigroup (Map k v)

(Semigroup a, Semigroup b, Semigroup c) => Semigroup (a, b, c)

(Semigroup a, Semigroup b, Semigroup c, Semigroup d) => Semigroup (a, b, c, d)

(Semigroup a, Semigroup b, Semigroup c, Semigroup d, Semigroup e) => Semigroup (a, b, c, d, e)

Semigroups

newtype Min a

Constructors

Min

Fields

getMin :: a

Instances

Typeable1 Min

Bounded a => Bounded (Min a)

Eq a => Eq (Min a)

Data a => Data (Min a)

Ord a => Ord (Min a)

Read a => Read (Min a)

Show a => Show (Min a)

(Ord a, Bounded a) => Monoid (Min a)

Ord a => Semigroup (Min a)

newtype Max a

Constructors

Max

Fields

getMax :: a

Instances

Typeable1 Max

Bounded a => Bounded (Max a)

Eq a => Eq (Max a)

Data a => Data (Max a)

Ord a => Ord (Max a)

Read a => Read (Max a)

Show a => Show (Max a)

(Ord a, Bounded a) => Monoid (Max a)

Ord a => Semigroup (Max a)

newtype First a

Use Option (First a) -- to get the behavior of Data.Monoid.First

Constructors

First

Fields

getFirst :: a

Instances

Typeable1 First

Bounded a => Bounded (First a)

Eq a => Eq (First a)

Data a => Data (First a)

Ord a => Ord (First a)

Read a => Read (First a)

Show a => Show (First a)

Semigroup (First a)

newtype Last a

Use Option (Last a) -- to get the behavior of Data.Monoid.Last

Constructors

Last

Fields

getLast :: a

Instances

Typeable1 Last

Bounded a => Bounded (Last a)

Eq a => Eq (Last a)

Data a => Data (Last a)

Ord a => Ord (Last a)

Read a => Read (Last a)

Show a => Show (Last a)

Semigroup (Last a)

newtype WrappedMonoid m

Constructors

WrapMonoid

Fields

unwrapMonoid :: m

Instances

Typeable1 WrappedMonoid

Bounded m => Bounded (WrappedMonoid m)

Eq m => Eq (WrappedMonoid m)

Data m => Data (WrappedMonoid m)

Ord m => Ord (WrappedMonoid m)

Read m => Read (WrappedMonoid m)

Show m => Show (WrappedMonoid m)

Monoid m => Monoid (WrappedMonoid m)

Monoid m => Semigroup (WrappedMonoid m)

Monoids from Data.Monoid

newtype Dual a

The dual of a monoid, obtained by swapping the arguments of mappend.

Constructors

Dual

Fields

getDual :: a

Instances

Bounded a => Bounded (Dual a)

Eq a => Eq (Dual a)

Ord a => Ord (Dual a)

Read a => Read (Dual a)

Show a => Show (Dual a)

Monoid a => Monoid (Dual a)

Semigroup a => Semigroup (Dual a)

newtype Endo a

The monoid of endomorphisms under composition.

Constructors

Endo

Fields

appEndo :: a -> a

Instances

Monoid (Endo a)

Semigroup (Endo a)

newtype All

Boolean monoid under conjunction.

Constructors

All

Fields

getAll :: Bool

Instances

Bounded All

Eq All

Ord All

Read All

Show All

Monoid All

Semigroup All

newtype Any

Boolean monoid under disjunction.

Constructors

Any

Fields

getAny :: Bool

Instances

Bounded Any

Eq Any

Ord Any

Read Any

Show Any

Monoid Any

Semigroup Any

newtype Sum a

Monoid under addition.

Constructors

Sum

Fields

getSum :: a

Instances

Bounded a => Bounded (Sum a)

Eq a => Eq (Sum a)

Ord a => Ord (Sum a)

Read a => Read (Sum a)

Show a => Show (Sum a)

Num a => Monoid (Sum a)

Num a => Semigroup (Sum a)

newtype Product a

Monoid under multiplication.

Constructors

Product

Fields

getProduct :: a

Instances

Bounded a => Bounded (Product a)

Eq a => Eq (Product a)

Ord a => Ord (Product a)

Read a => Read (Product a)

Show a => Show (Product a)

Num a => Monoid (Product a)

Num a => Semigroup (Product a)

A better monoid for Maybe

newtype Option a

Option is effectively Maybe with a better instance of Monoid, built off of an underlying Semigroup instead of an underlying Monoid. Ideally, this type would not exist at all and we would just fix the Monoid intance of Maybe

Constructors

Option

Fields

getOption :: Maybe a

Instances

Monad Option

Functor Option

Typeable1 Option

MonadFix Option

MonadPlus Option

Applicative Option

Foldable Option

Traversable Option

Alternative Option

Eq a => Eq (Option a)

Data a => Data (Option a)

Ord a => Ord (Option a)

Read a => Read (Option a)

Show a => Show (Option a)

Semigroup a => Monoid (Option a)

Semigroup a => Semigroup (Option a)

option :: b -> (a -> b) -> Option a -> b

Difference lists of a semigroup

diff :: Semigroup m => m -> Endo m

This lets you use a difference list of a Semigroup as a Monoid.