error when parsing numeric field for a specific file open by ifstream

[sangoblin]

test.csv

all the datas under the column "ets" are intergers. However, if I choose to open the file using ifstream (the code is listed as below), the program will complain that the data field is not a number.

#include <csv.hpp>
#include
#include

using namespace std;
using csv::CSVReader, csv::CSVRow;

int main(int argc, const char** argv)
{
ifstream ifs("test.csv");

for (auto&& row : CSVReader{ifs})
{
    const auto ets= row["ets"].get<long>();
    cout << ets << endl;
}

}

However, if I read the csv by file name directly, i.e., CSVReader("test.csv"), the program could run normally.

Could you please kindly investigate this issue? Thanks.