sequence benchmarking

benchmark.kt

fun main(args: Array<String>) {
    val result = mutableListOf<Pair<Long, Long>>()
    repeat(100) {
        result.add(task())
    }
    println("====================")
    println("LIST TIME (ns)   ||    SEQUENCE TIME (ns)")
    result.forEach {
        println("  ${it.first}       ||    ${it.second}      || delta ${it.first - it.second}  ")
    }
}

fun task(): Pair<Long, Long> {
    val list = "The quick brown fox jumps over the lazy dog".repeat(100).split(" ")
    val sequence = list.asSequence()

    val listTime = measureNanoTime {
        normalList(list)
    }
    val seqTime = measureNanoTime {
        sequence(sequence)
    }
    return listTime to seqTime
}


fun normalList(list: List<String>) {
    list.filter {
        println("filter: $it");
        it.length > 3
    }
        .map { it + it }
        .map { it.length }
        .take(4)
}

fun sequence(seq: Sequence<String>) {
    seq.filter {
        println("filter: $it");
        it.length > 3
    }
        .map { it + it }
        .map { it.length }
        .take(4)
}