arrow-fx-coroutines / arrow.fx.coroutines.stream / Stream / exists

exists

fun exists(f: (O) -> Boolean): Stream<Boolean>

Emits true as soon as a matching element is received, else false if no input matches.

import arrow.fx.coroutines.stream.*

//sampleStart
suspend fun main(): Unit {
  Stream.range(0..10).exists { it == 4 }
    .toList().let(::println) //[true]

  Stream.range(0..10).exists { it == 11 }
    .toList().let(::println) //[false]
}
//sampleEnd

Return Either a singleton stream, or a never stream.