Dmitry Petrov
37 lines
826 B
Kotlin
Vendored
37 lines
826 B
Kotlin
Vendored
// WITH_RUNTIME
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import kotlin.contracts.ExperimentalContracts
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import kotlin.contracts.InvocationKind
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import kotlin.contracts.contract
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data class Content<out T>(val value: T)
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fun <T> content(value: T) = Content(value)
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@ExperimentalContracts
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inline fun <R, T : R> Content<T>.getOrElse(
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onException: (exception: Exception) -> R,
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): R = fold({ it }, onException)
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@ExperimentalContracts
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inline fun <R, T> Content<T>.fold(
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onContent: (value: T) -> R,
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onException: (exception: Exception) -> R,
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): R {
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contract {
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callsInPlace(onContent, InvocationKind.AT_MOST_ONCE)
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callsInPlace(onException, InvocationKind.AT_MOST_ONCE)
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}
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return onContent(value)
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}
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@ExperimentalContracts
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fun box(): String {
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val t = content(1).getOrElse { 2 }
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if (t != 1) return "Failed: $t"
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return "OK"
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}
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