acquireN

import arrow.fx.*
import arrow.fx.extensions.io.async.async
import arrow.fx.extensions.io.monad.flatMap

fun main(args: Array<String>) {
  //sampleStart
  val semaphore = Semaphore.uncancellable<ForIO>(5, IO.async())

  semaphore.flatMap { s ->
    s.acquireN(6)
  } //Never ends since is uncancellable

  semaphore.flatMap { s ->
    s.acquireN(5).flatMap {
      s.available()
    }
  }.unsafeRunSync() == 0L
  //sampleEnd
}