@file:Suppress("UNCHECKED_CAST")

data class Element<T>(
    val key: String,
    val valueOne: T,
    val valueTwo: T,
    val comparator: Comparator<T>,
    val comparatorValue: CompareResult
)

enum class CompareResult(
    val value: Int
) {
    LESS(-1),
    EQUAL(0),
    GREATER_THAN(1)
}

fun <T> matchesComparison(list:Collection<Element<T>>): Pair<Boolean, List<String>> {
    val failedComparisons = mutableListOf<String>()
    for (element in list) {
        val compareValue = element.comparator.compare(element.valueOne, element.valueTwo)
        if (element.comparatorValue.value != compareValue) {
            failedComparisons.add(element.key)
        }
    }
    return Pair(failedComparisons.isEmpty(), failedComparisons)
}

val stringComparator = Comparator.comparing(String::toString)
val intComparator = Comparator.comparing(Int::toInt)

val elementsToCompare = listOf(
    Element("number", 1, 2, intComparator, CompareResult.LESS),
    Element("first name", "a", "a", stringComparator, CompareResult.EQUAL),
    Element("last name", "a", "b", stringComparator, CompareResult.EQUAL)
)

matchesComparison(elementsToCompare).second.joinToString(", ","Failed elements: \"","\"")

我经常面临比较两个具有相同值的不同对象属性的问题。例如，对象A具有props number，firstname，lastname.我想做的是创建一个列表have和have函数来遍历这些元素并返回哪些 prop 没有通过比较，我已经设法为对象和matchesComparison函数使用了泛型，matchesComparison函数返回失败的比较。当我想把这个类型为Collection〈Element〈out Any〉〉的列表传递给这个函数时，问题就开始了，我得到了一个类型missmatch。与其使用未检查的强制转换来强制比较器为Any类型，我宁愿这样做

val stringComparator = Comparator.comparing(String::toString) 
val intComparator = Comparator.comparing(Int::toInt)

上述脚本的结果值应为Failed elements: "last name"
我尝试将函数的签名改为out any，但是comparator.compare方法的两个参数都是Nothing类型。我真的希望避免取消未检查的强制转换。