Pavel Kunyavskiy
64 lines
1.4 KiB
Kotlin
Vendored
64 lines
1.4 KiB
Kotlin
Vendored
interface Monoid<T : Any?> : Semigroup<T> {
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abstract val unit: T
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abstract get
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}
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interface Semigroup<T : Any?> {
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abstract infix fun T.combine(other: T): T
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}
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object IntMonoid : Monoid<Int> {
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override val unit: Int
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field = 0
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override get
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private constructor() /* primary */ {
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super/*Any*/()
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/* <init>() */
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}
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override infix fun Int.combine(other: Int): Int {
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return <this>.plus(other = other)
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}
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}
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object StringMonoid : Monoid<String> {
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override val unit: String
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field = ""
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override get
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private constructor() /* primary */ {
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super/*Any*/()
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/* <init>() */
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}
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override infix fun String.combine(other: String): String {
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return <this>.plus(other = other)
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}
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}
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fun box(): String {
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with<IntMonoid, Int>(receiver = IntMonoid, block = local fun IntMonoid.<anonymous>(): Int {
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return listOf<Int>(elements = [1, 2, 3]).sum<Int>($context_receiver_0 = $this$with)
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}
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) /*~> Unit */
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return with<StringMonoid, String>(receiver = StringMonoid, block = local fun StringMonoid.<anonymous>(): String {
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return listOf<String>(elements = ["O", "K"]).sum<String>($context_receiver_0 = $this$with)
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}
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)
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}
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fun <T : Any?> List<T>.sum($context_receiver_0: Monoid<T>): T {
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return <this>.fold<T, T>(initial = $context_receiver_0.<get-unit>(), operation = local fun <anonymous>(acc: @ParameterName(name = "acc") T, e: T): T {
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return ($context_receiver_0, acc).combine(other = e)
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}
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)
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}
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