Package io.atlassian.fugue

Class Monoids

java.lang.Object

io.atlassian.fugue.Monoids

public final class Monoids
extends java.lang.Object

Monoid instances.

Since:

3.0

See Also:

Semigroups

Field Summary

Fields

Modifier and Type	Field	Description
static Monoid<java.math.BigInteger>	bigintAddition	A monoid that adds big integers.
static Monoid<java.math.BigInteger>	bigintMultiplication	A monoid that multiplies big integers.
static Monoid<java.lang.Boolean>	conjunction	A monoid that ANDs booleans.
static Monoid<java.lang.Boolean>	disjunction	A monoid that ORs booleans.
static Monoid<java.lang.Boolean>	exclusiveDisjunction	A monoid that XORs booleans.
static Monoid<java.lang.Integer>	intAddition	A monoid that adds integers.
static Monoid<java.lang.Integer>	intMultiplication	A monoid that multiplies integers.
static Monoid<java.lang.Long>	longAddition	A monoid that adds longs.
static Monoid<java.lang.Long>	longMultiplication	A monoid that multiplies longs.
static Monoid<java.lang.String>	string	A monoid that appends strings.
static Monoid<Unit>	unit	A monoid for the Unit value.

Constructor Summary

Constructors

Modifier	Constructor	Description
private	Monoids()

Method Summary

Modifier and Type	Method	Description
static <L,R> Monoid<Either<L,R>>	either(Semigroup<L> lS, Monoid<R> rM)	A monoid Sums up values inside either Semigroups.either(io.atlassian.fugue.Semigroup<L>, io.atlassian.fugue.Semigroup<R>).
static <A> Monoid<Option<A>>	firstOption()	A monoid for options (that take the first available value).
static <A,B> Monoid<java.util.function.Function<A,B>>	function(Monoid<B> mb)	A monoid for functions.
static <A> Monoid<java.lang.Iterable<A>>	iterable()	A monoid for iterables.
static <A> Monoid<Option<A>>	lastOption()	A monoid for options that take the last available value.
static <A> Monoid<java.util.List<A>>	list()	A monoid for lists.
static <A> Monoid<Option<A>>	option(Semigroup<A> semigroup)	A monoid for options that combine inner value with a semigroup.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

intAddition

public static final Monoid<java.lang.Integer> intAddition

A monoid that adds integers.

intMultiplication

public static final Monoid<java.lang.Integer> intMultiplication

A monoid that multiplies integers.

bigintAddition

public static final Monoid<java.math.BigInteger> bigintAddition

A monoid that adds big integers.

bigintMultiplication

public static final Monoid<java.math.BigInteger> bigintMultiplication

A monoid that multiplies big integers.

longAddition

public static final Monoid<java.lang.Long> longAddition

A monoid that adds longs.

longMultiplication

public static final Monoid<java.lang.Long> longMultiplication

A monoid that multiplies longs.

disjunction

public static final Monoid<java.lang.Boolean> disjunction

A monoid that ORs booleans.

exclusiveDisjunction

public static final Monoid<java.lang.Boolean> exclusiveDisjunction

A monoid that XORs booleans.

conjunction

public static final Monoid<java.lang.Boolean> conjunction

A monoid that ANDs booleans.

string

public static final Monoid<java.lang.String> string

A monoid that appends strings.

unit

public static final Monoid<Unit> unit

A monoid for the Unit value.

Constructor Detail

Monoids

private Monoids()

Method Detail

function

public static <A,B> Monoid<java.util.function.Function<A,B>> function(Monoid<B> mb)

A monoid for functions.

Type Parameters:

A - input type

B - composable output type

Parameters:

mb - The monoid for the function codomain.

Returns:

A monoid for functions.

list

public static <A> Monoid<java.util.List<A>> list()

A monoid for lists.

Type Parameters:

A - internal type

Returns:

A monoid for lists.

iterable

public static <A> Monoid<java.lang.Iterable<A>> iterable()

A monoid for iterables.

Type Parameters:

A - internal type

Returns:

A monoid for iterables.

firstOption

public static <A> Monoid<Option<A>> firstOption()

A monoid for options (that take the first available value).

Type Parameters:

A - internal type

Returns:

A monoid for options (that take the first available value).

lastOption

public static <A> Monoid<Option<A>> lastOption()

A monoid for options that take the last available value.

Type Parameters:

A - internal type

Returns:

A monoid for options that take the last available value.

option

public static <A> Monoid<Option<A>> option(Semigroup<A> semigroup)

A monoid for options that combine inner value with a semigroup.

Type Parameters:

A - internal type

Parameters:

semigroup - a Semigroup object.

Returns:

A monoid for options that combine inner value with a semigroup.

either

public static <L,R> Monoid<Either<L,R>> either(Semigroup<L> lS,
                                                           Monoid<R> rM)

A monoid Sums up values inside either Semigroups.either(io.atlassian.fugue.Semigroup<L>, io.atlassian.fugue.Semigroup<R>). Monoid of right values provide the identity element of the resulting monoid.

Type Parameters:

L - desired left type

R - desired right type

Parameters:

lS - semigroup for left values

rM - monoid for right values.

Returns:

A monoid Sums up values inside either.