Ilya Kirillov
1bbcae5ed2
We cannot call lazy resolve to STATUS phase from scopes as scopes may be accessed on a STATUS phase or earlier ^KT-54890 ^KTIJ-23587 fixed
36 lines
874 B
Kotlin
Vendored
36 lines
874 B
Kotlin
Vendored
// FIR_IDENTICAL
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// !LANGUAGE: +ContextReceivers
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interface Semigroup<T> {
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infix fun T.combine(other: T): T
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}
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interface Monoid<T> : Semigroup<T> {
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val unit: T
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}
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object IntMonoid : Monoid<Int> {
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override fun Int.combine(other: Int): Int = this + other
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override val unit: Int = 0
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}
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object StringMonoid : Monoid<String> {
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override fun String.combine(other: String): String = this + other
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override val unit: String = ""
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}
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public inline fun <T, R> Iterable<T>.fold(initial: R, operation: (acc: R, T) -> R): R = TODO()
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context(Monoid<T>)
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fun <T> List<T>.sum(): T = fold(unit) { acc, e -> acc.combine(e) }
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fun <T> listOf(vararg items: T): List<T> = null!!
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fun test() {
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with(IntMonoid) {
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listOf(1, 2, 3).sum()
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}
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with(StringMonoid) {
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listOf(1, 2, 3).<!NO_CONTEXT_RECEIVER!>sum<!>()
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listOf("1", "2", "3").sum()
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}
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}
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