function numberToUint8Array64LE_DataView(num) {

    const buf = new ArrayBuffer(8)

    const view = new DataView(buf)

    view.setUint32(0, num, true)

    view.setUint32(4, num >>> 32, true)

    return new Uint8Array(buf)

}

​

function numberToUint8Array64LE_direct(num) {

    const result = new Uint8Array(8)

    result[0] = num & 0xff

    result[1] = (num >>> 8) & 0xff

    result[2] = (num >>> 16) & 0xff

    result[3] = (num >>> 24) & 0xff

    result[4] = (num >>> 32) & 0xff

    result[5] = (num >>> 40) & 0xff

    result[6] = (num >>> 48) & 0xff

    result[7] = (num >>> 56) & 0xff

    return result

}

​

function numberToUint8Array64LE_bigint(num) {

    const bigIntValue = BigInt.asUintN(64, BigInt(num));

    const buffer = new ArrayBuffer(8);

    const dataView = new DataView(buffer);

    dataView.setBigUint64(0, bigIntValue, true);

    return Uint8Array.from(buffer.slice(0, 8));

}

​

function numberToUint8Array64LE_withLoop(num) {

    const result = new Uint8Array(8)

    for (let i = 0; i < 8; i++) {

        result[i] = num & 0xff

        num = num >>> 8

    }

    return result

}

​

function numberToUint8Array64LE_withLoop_noAssignment(num) {

    const result = new Uint8Array(8)

    result[0] = num & 0xff

    for (let i = 1, j = 8; i < 8; i++, j += 8) {

        result[i] = (num >>> j) & 0xff

    }

    return result

}

​

function numberToUint8Array64LE_withLoop_noAssignment_noSecondCounter(num) {

    const result = new Uint8Array(8)

    result[0] = num & 0xff

    for (let i = 1; i < 8; i++) {

        result[i] = (num >>> (i << 3)) & 0xff

    }

    return result

}

​

function numberToUint8Array64LE_withLoop_bugoutOn0(num) {

    const result = new Uint8Array(8)

    for (let i = 0; num != 0; i++, num = num >>> 8) {

        result[i] = num & 0xff

    }

    return result

}