如何使用Kotlin将字符串拆分成N个字母的部分？

fun String.splitIntoParts(N: Int): List<String> {
    val parts = mutableListOf<String>()
    var index = 0
    while (index < length) {
        val endIndex = minOf(index + N, length)
        parts.add(substring(index, endIndex))
        index += N
    }
    return parts
}

val str = "HelloWorld"
val parts = str.splitIntoParts(3)
println(parts) // 输出：[Hel, loW, orl, d]