blob: 13d55e79f778382d52721b7f34799dabdde74d39 [file] [log] [blame]
// !OPT_IN: kotlin.contracts.ExperimentalContracts
// WITH_STDLIB
import kotlin.contracts.ExperimentalContracts
import kotlin.contracts.InvocationKind
import kotlin.contracts.contract
data class Content<out T>(val value: T)
fun <T> content(value: T) = Content(value)
@ExperimentalContracts
inline fun <R, T : R> Content<T>.getOrElse(
onException: (exception: Exception) -> R,
): R = fold({ it }, onException)
@ExperimentalContracts
inline fun <R, T> Content<T>.fold(
onContent: (value: T) -> R,
onException: (exception: Exception) -> R,
): R {
contract {
callsInPlace(onContent, InvocationKind.AT_MOST_ONCE)
callsInPlace(onException, InvocationKind.AT_MOST_ONCE)
}
return onContent(value)
}
@ExperimentalContracts
fun box(): String {
val t = content(1).getOrElse { 2 }
if (t != 1) return "Failed: $t"
return "OK"
}