AbstractListIterator.kt
/*
* Copyright 2016-2019 JetBrains s.r.o.
* Use of this source code is governed by the Apache 2.0 License that can be found in the LICENSE.txt file.
*/
package androidx.compose.runtime.external.kotlinx.collections.immutable.implementations.immutableList
internal abstract class AbstractListIterator<out E>(var index: Int, var size: Int) : ListIterator<E> {
override fun hasNext(): Boolean {
return index < size
}
override fun hasPrevious(): Boolean {
return index > 0
}
override fun nextIndex(): Int {
return index
}
override fun previousIndex(): Int {
return index - 1
}
internal fun checkHasNext() {
if (!hasNext())
throw NoSuchElementException()
}
internal fun checkHasPrevious() {
if (!hasPrevious())
throw NoSuchElementException()
}
}
internal class SingleElementListIterator<E>(private val element: E, index: Int): AbstractListIterator<E>(index, 1) {
override fun next(): E {
checkHasNext()
index++
return element
}
override fun previous(): E {
checkHasPrevious()
index--
return element
}
}