kotlin - test List<Int> is ascending

fun isAscending(list: List<Int>):Boolean {
    return list.let {
        var tempResult = true
        it.forEachIndexed { idx, item ->
            tempResult = if (idx != it.lastIndex) item < it[idx + 1] else true
            if (!tempResult) return@let tempResult
        }
        tempResult
    }
}