Is there a C++ iterator that can iterate over a file line by line?

EDIT: This same trick was already posted by someone else in a previous thread.

It is easy to have std::istream_iterator do what you want:

namespace detail 
{
    class Line : std::string 
    { 
        friend std::istream & operator>>(std::istream & is, Line & line)
        {   
            return std::getline(is, line);
        }
    };
}

template<class OutIt>
void read_lines(std::istream& is, OutIt dest)
{
    typedef std::istream_iterator<detail::Line> InIt;
    std::copy(InIt(is), InIt(), dest);
}

int main()
{
    std::vector<std::string> v;
    read_lines(std::cin, std::back_inserter(v));

    return 0;
}

Here is a solution. The exemple print the input file with @@ at the end of each line.

#include <iostream>
#include <iterator>
#include <fstream>
#include <string>

using namespace std;

class line : public string {};

std::istream &operator>>(std::istream &is, line &l)
{
    std::getline(is, l);
    return is;
}

int main()
{
    std::ifstream inputFile("input.txt");

    istream_iterator<line> begin(inputFile);
    istream_iterator<line> end;

    for(istream_iterator<line> it = begin; it != end; ++it)
    {
        cout << *it << "@@\n";
    }

    getchar();
}

Edit : Manuel has been faster.

The standard library does not provide iterators to do this (although you can implement something like that on your own), but you can simply use the getline function (not the istream method) to read a whole line from an input stream to a C++ string.

Example:

#include <iostream>
#include <fstream>
#include <string>
#include <algorithm>

using namespace std;

int main()
{
    ifstream is("test.txt");
    string str;
    while(getline(is, str))
    {
        cout<<str<<endl;
    }
    return 0;
}