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Class WithFilter.WithFilter

Source code

abstract class WithFilter[+A, +CC[_]] extends Serializable

A template trait that contains just the map, flatMap, foreach and withFilter methods of trait Iterable.

Type parameters
A

Element type (e.g. Int)

CC

Collection type constructor (e.g. List)
Supertypes
trait Serializable
class Object
trait Matchable
class Any
Known subtypes
class WithFilter[A, CC]
class WithFilter[K, V, IterableCC, CC]
class WithFilter[K, V, IterableCC, MapCC, CC]
class WithFilter[A, IterableCC, CC]

Abstract methods

Source
def flatMap[B](f: A => IterableOnce[B]): CC[B]

Builds a new collection by applying a function to all elements of the filtered outer collection containing this WithFilter instance that satisfy

Type parameters
B

the element type of the returned collection.
Value parameters
f

the function to apply to each element.
Returns

a new collection resulting from applying the given collection-valued function f to each element of the filtered outer collection and concatenating the results.

Source
def foreach[U](f: A => U): Unit

Applies a function f to all elements of the filtered outer collection.

Type parameters
U

the type parameter describing the result of function f. This result will always be ignored. Typically U is Unit, but this is not necessary.
Value parameters
f

the function that is applied for its side-effect to every element. The result of function f is discarded.

Source
def map[B](f: A => B): CC[B]

Builds a new collection by applying a function to all elements of the filtered outer collection.

Type parameters
B

the element type of the returned collection.
Value parameters
f

the function to apply to each element.
Returns

a new collection resulting from applying the given function f to each element of the filtered outer collection and collecting the results.

Source
def withFilter(q: A => Boolean): WithFilter[A, CC]

Further refines the filter for this filtered collection.

Value parameters
q

the predicate used to test elements.
Returns

an object of class WithFilter, which supports map, flatMap, foreach, and withFilter operations. All these operations apply to those elements of this collection which also satisfy both p and q predicates.

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Licensed under the Apache License, Version 2.0.
https://scala-lang.org/api/3.2.0/scala/collection/WithFilter.html