Mads Ager
36 lines
540 B
Kotlin
Vendored
36 lines
540 B
Kotlin
Vendored
// !OPT_IN: kotlin.contracts.ExperimentalContracts
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// WITH_STDLIB
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import kotlin.contracts.*
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fun runOnce(action: () -> Unit) {
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contract {
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callsInPlace(action, InvocationKind.EXACTLY_ONCE)
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}
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action()
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}
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fun o(): String {
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var res = "FAIL1 "
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("O" to "").let { (a, _) ->
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runOnce {
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res = a
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}
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}
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return res
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}
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fun k(): String {
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val res: String
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"K".let { b ->
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runOnce {
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res = b
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}
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}
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return res
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}
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fun box(): String {
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return o() + k()
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}
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