Cats kernel/cats.kernel.instances/Function1Monoid

Function1Monoid

trait Function1Monoid[A, B] extends Function1Semigroup[A, B] with Monoid[A => B]
trait Monoid[A => B]
trait Semigroup[A => B]
trait Serializable
class Object
trait Matchable
class Any
trait Function1Group[A, B]

Value members

Inherited methods

override def combine(x: A => B, y: A => B): A => B
Definition Classes
Inherited from
Function1Semigroup
def combineAll(as: IterableOnce[A => B]): A => B

Given a sequence of as, sum them using the monoid and return the total.

Given a sequence of as, sum them using the monoid and return the total.

Example:

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

scala> Monoid[String].combineAll(List("One ", "Two ", "Three"))
res0: String = One Two Three

scala> Monoid[String].combineAll(List.empty)
res1: String = ""
Inherited from
Monoid
override def combineAllOption(as: IterableOnce[A => B]): Option[A => B]
Definition Classes
Inherited from
Monoid
override def combineN(a: A => B, n: Int): A => B

Return a appended to itself n times.

Return a appended to itself n times.

Example:

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

scala> Monoid[String].combineN("ha", 3)
res0: String = hahaha

scala> Monoid[String].combineN("ha", 0)
res1: String = ""
Definition Classes
Inherited from
Monoid
def intercalate(middle: A => B): Semigroup[A => B]

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
def isEmpty(a: A => B)(ev: Eq[A => B]): Boolean

Tests if a is the identity.

Tests if a is the identity.

Example:

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

scala> Monoid[String].isEmpty("")
res0: Boolean = true

scala> Monoid[String].isEmpty("something")
res1: Boolean = false
Inherited from
Monoid
override def reverse: Monoid[A => B]
Definition Classes
Inherited from
Monoid

Concrete fields

val empty: A => B

Implicits

Implicits

implicit def B: Monoid[B]