Class

com.twitter.algebird

JMapMonoid

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class JMapMonoid[K, V] extends Monoid[Map[K, V]]

Since maps are mutable, this always makes a full copy. Prefer scala immutable maps if you use scala immutable maps, this operation is much faster TODO extend this to Group, Ring

Source: JavaMonoids.scala

Linear Supertypes

Monoid[Map[K, V]], Semigroup[Map[K, V]], Serializable, AnyRef, Any

Type Hierarchy

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JMapMonoid
Monoid
Semigroup
Serializable
AnyRef
Any

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Visibility

Public
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Instance Constructors

new JMapMonoid()(implicit arg0: Semigroup[V])

Value Members

final def !=(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def ##(): Int

Definition Classes
AnyRef → Any
final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any
final def asInstanceOf[T0]: T0

Definition Classes
Any
def assertNotZero(v: Map[K, V]): Unit

Definition Classes
Monoid
def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( ... )
final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef
def equals(arg0: Any): Boolean

Definition Classes
AnyRef → Any
def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
@throws( classOf[java.lang.Throwable] )
final def getClass(): Class[_]

Definition Classes
AnyRef → Any
def hashCode(): Int

Definition Classes
AnyRef → Any
final def isInstanceOf[T0]: Boolean

Definition Classes
Any
def isNonZero(x: Map[K, V]): Boolean

Definition Classes
JMapMonoid → Monoid
final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef
val nonZero: (V) ⇒ Boolean
def nonZeroOption(v: Map[K, V]): Option[Map[K, V]]

Definition Classes
Monoid
final def notify(): Unit

Definition Classes
AnyRef
final def notifyAll(): Unit

Definition Classes
AnyRef
def plus(x: Map[K, V], y: Map[K, V]): HashMap[K, V]

Combines two T instances associatively.
Combines two T instances associatively.
returns
result of combining l and r

Definition Classes
JMapMonoid → Semigroup
def sum(vs: TraversableOnce[Map[K, V]]): Map[K, V]

Definition Classes
Monoid
def sumOption(iter: TraversableOnce[Map[K, V]]): Option[Map[K, V]]

Returns an instance of T calculated by summing all instances in iter in one pass.
Returns an instance of T calculated by summing all instances in iter in one pass. Returns None if iter is empty, else Some[T].
iter
instances of T to be combined
returns
None if iter is empty, else an option value containing the summed T

Definition Classes
Semigroup
Note
Override if there is a faster way to compute this sum than iter.reduceLeftOption using plus.
final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
AnyRef
def toString(): String

Definition Classes
AnyRef → Any
final def wait(): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
@throws( ... )
lazy val zero: HashMap[K, V]

Returns the identity element of T for plus.
Returns the identity element of T for plus.

Definition Classes
JMapMonoid → Monoid

Inherited from Monoid[Map[K, V]]

Inherited from Semigroup[Map[K, V]]

Inherited from Serializable

Inherited from AnyRef

Inherited from Any

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