void main() {
    // json: https://github.com/nlohmann/json
    // 所有的对像返回用Valid来判断是否有效
    LogProfitReset();
    LogReset();
    Log(_N(9.12345, 2));
    Log("use _C", _C(exchange.GetTicker), _C(exchange.GetAccount));

    // 测试异步并发
    auto routineTicker = exchange.Go("GetTicker");
    auto routineDepth = exchange.Go("GetDepth");
    Ticker asyncTicker;