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

fold

fun <B> fold(initial: B, f: (B, O) -> B): Stream<B>

Folds all inputs using an initial value z and supplied binary operator, and emits a single element stream.

import arrow.fx.coroutines.stream.*

//sampleStart
suspend fun main(): Unit =
  Stream(1, 2, 3, 4, 5)
  .fold(0) { acc, b -> acc + b }
  .toList()
  .let(::println) //[15]
//sampleEnd