dropWhile

Drop elements as long as a predicate function return true for the element

Simple operators

Signature¶

Source.dropWhileSource.dropWhile Flow.dropWhileFlow.dropWhile

Description¶

Drop elements as long as a predicate function return true for the element

Example¶

Given a Source of ordered numbers we can drop all the negative ones with the dropWhile operator. Mind that after the first non negative number is encountered, all the consecutive elements will be emitted despite the predicate provided.

Scala

Java

copysourceval droppedWhileNegative = Source(-3 to 3).dropWhile(_ < 0)

droppedWhileNegative.runForeach(println)
// 0
// 1
// 2
// 3

copysourceSource<Integer, NotUsed> droppedWhileNegative =
    Source.from(Arrays.asList(-3, -2, -1, 0, 1, 2, 3, -1)).dropWhile(integer -> integer < 0);

droppedWhileNegative.runForeach(System.out::println, system);
// 1
// 2
// 3
// -1

Reactive Streams semantics¶