Question

I’m tring to search a text file and extract the data after a heading. However, I’ve got some issues with iterators that I don’t know how to overcome.

This is a sample text file:

Relay States
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0

Ideally, I’d like to call LoadData<bool> something.LoadData("Relay States"); and have it return an std::vector with {0,0,0,0,0,0,0,0,…}.

template<typename T> std::vector<T> CProfile::LoadData(const std::string& name)
{
    std::ifstream ifs(FILE_NAME);
    std::vector<T> data;
    std::istreambuf_iterator<char> iit = std::istreambuf_iterator<char>(ifs);

    std::search(iit, ifs.eof(), name.begin(), name.end());
    std::advance(iit, name.size() + 1);

    T buffer = 0;
    for(ifs.seekg(iit); ifs.peek() != '\n' && !ifs.eof(); data.push_back(ifs))
    {
        ifs >> buffer;
        data.push_back(buffer);
    }

    return data;
}

From what I understand, the main problems with my code are:

• std::search is an ambiguous call, how would I go about fixing this?
• ifs.seekg(iit) is not legal, how would I go about making iit a valid argument?

Thanks.

Answer 1

Well I think your args to std::search is problem

std::search(iit, ifs.eof(), name.begin(), name.end());

should be

std::search(iit, std::istreambuf_iterator<char>(), name.begin(), name.end());

as for line : ifs.seekg(iit) in for loop isn’t good , since seekg expects some offset of type streampos not an iterator. so it should be ifs.seekg(0)