Alg
Attributes
- Source
- Helpers.scala
- Graph
-
- Supertypes
-
trait CommutativeMonoid[CMono]trait CommutativeSemigroup[CMono]trait Serializableclass Objecttrait Matchableclass AnyShow all
- Self type
-
Alg.type
Members list
Value members
Concrete methods
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)
Attributes
- Source
- Helpers.scala
Return the identity element for this monoid.
Return the identity element for this monoid.
Example:
scala> import cats.kernel.instances.int._
scala> import cats.kernel.instances.string._
scala> Monoid[String].empty
res0: String = ""
scala> Monoid[Int].empty
res1: Int = 0
Attributes
- Source
- Helpers.scala
Inherited methods
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 = ""
Attributes
- Inherited from:
- Monoid
- Source
- Monoid.scala
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
Attributes
- Definition Classes
- Inherited from:
- Monoid
- Source
- Monoid.scala
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 = ""
Attributes
- Definition Classes
- Inherited from:
- =0")elseif(n.==(0))Monoid.this.emptyelseMonoid.this.repeatedCombineN(a,n)">Monoid
- Source
- Monoid.scala
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.
Attributes
- Definition Classes
- Inherited from:
- CommutativeSemigroup
- Source
- CommutativeSemigroup.scala
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
Attributes
- Inherited from:
- Monoid
- Source
- Monoid.scala
return a semigroup that reverses the order so combine(a, b) == reverse.combine(b, a)
return a semigroup that reverses the order so combine(a, b) == reverse.combine(b, a)
Attributes
- Definition Classes
- Inherited from:
- CommutativeMonoid
- Source
- CommutativeMonoid.scala