ZeroSemigroup

trait ZeroSemigroup[@specialized(Int, Long, Float, Double) A] extends Semigroup[A]

A zero semigroup is a semigroup with an absorbing element. A zero semigroup is a specialization of a semigroup, so its operation must be associative. Additionally, combine(x, absorbing) == combine(absorbing, x) == absorbing. For example, if we have ZeroSemigroup[Int], with combine as integer multiplication, then absorbing == 0.

A zero semigroup is a semigroup with an absorbing element. A zero semigroup is a specialization of a semigroup, so its operation must be associative. Additionally, combine(x, absorbing) == combine(absorbing, x) == absorbing. For example, if we have ZeroSemigroup[Int], with combine as integer multiplication, then absorbing == 0.

Companion
object
trait Semigroup[A]
trait Serializable
class Any

Value members

Abstract methods

def absorbing: A

Return the absorbing element for this zero semigroup.

Return the absorbing element for this zero semigroup.

Concrete methods

def isAbsorbing(a: A)(ev: Eq[A]): Boolean

Tests if a is the absorbing element.

Tests if a is the absorbing element.

override def reverse: ZeroSemigroup[A]
Definition Classes
Semigroup

Inherited methods

def combine(x: A, y: A): A

Associative operation which combines two values.

Associative operation which combines two values.

Example:

scala> import cats.kernel.instances.string._
scala> import cats.kernel.instances.int._
scala> import cats.kernel.instances.option._

scala> Semigroup[String].combine("Hello ", "World!")
res0: String = Hello World!

scala> Semigroup[Option[Int]].combine(None, Some(1))
res1: Option[Int] = Some(1)
Inherited from
Semigroup
def combineAllOption(as: IterableOnce[A]): Option[A]

Given a sequence of as, combine them and return the total.

Given a sequence of as, combine them and return the total.

If the sequence is empty, returns None. Otherwise, returns Some(total).

Example:

scala> import cats.kernel.instances.string._

scala> Semigroup[String].combineAllOption(List("One ", "Two ", "Three"))
res0: Option[String] = Some(One Two Three)

scala> Semigroup[String].combineAllOption(List.empty)
res1: Option[String] = None
Inherited from
Semigroup
def combineN(a: A, n: Int): A

Return a combined with itself n times.

Return a combined with itself n times.

Example:

scala> import cats.kernel.instances.int._
scala> import cats.kernel.instances.string._

scala> Semigroup[Int].combineN(1, 10)
res0: Int = 10

scala> Semigroup[String].combineN("ha", 3)
res1: String = hahaha
Inherited from
Semigroup
def intercalate(middle: A): Semigroup[A]

Between each pair of elements insert middle This name matches the term used in Foldable and Reducible and a similar Haskell function.

Between each pair of elements insert middle This name matches the term used in Foldable and Reducible and a similar Haskell function.

Inherited from
Semigroup