Victor Petukhov
14 lines
314 B
Kotlin
Vendored
14 lines
314 B
Kotlin
Vendored
sealed class Subtype<A1, B1> {
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abstract fun cast(value: A1): B1
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class Trivial<A2 : B2, B2> : Subtype<A2, B2>() {
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override fun cast(value: A2): B2 = value
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}
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}
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fun <A, B> unsafeCast(value: A): B {
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val proof: Subtype<A, B> = Subtype.Trivial()
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return proof.cast(value)
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}
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fun box() = "OK"
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