Question

I am wondering how to read in and edit a text file by searching for lines containing foobar and then erasing those lines only. Don’t need a full program, if someone could just point me towards the right fstream functions.

Answer 1

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

class line {
    std::string data;
public:
    friend std::istream &operator>>(std::istream &is, line &l) {
        std::getline(is, l.data);
        return is;
    }
    operator std::string() const { return data; }    
};

int main() {      
    std::remove_copy_if(std::istream_iterator<line>(std::cin),
                        std::istream_iterator<line>(),
                        std::ostream_iterator<std::string>(std::cout, "\n"),
                        [](std::string const &s) { 
                            return s.find("foobar") != std::string::npos;
                        });
    return 0;
}