Iterating on std::map results in segmentation fault

[wangkhem]

void call(function<void ()> f) {
    f();
}
void end() {
    cout << "End..." << endl;
}
void fn(map<string, string> &m, map<string, string>::iterator i) {
    cout << "i->first: " << i->first << endl;
    if (++i == m.end()) {
        end();
    } else {
        call(bind(&fn, m, i));
    }
}
int main() {
    map<string, string> m;
    m["abc"] = "asasd";
    m["bcd"] = "sasas";
    m["cde"] = "jdssd";
 
    call(bind(&fn, m, m.begin()));
}
 

The above code results in segmentation fault. Kindly help me find where im I wrong.

[akdemirc]

in fn function you are trying to access the first element of the iterator without checking its value (when it reaches the end of map, it will cause segmentation if you try to print), try this

if (i != m.end())
{ 
     cout << "i->first: " << i->first << endl; 
}

[wangkhem]

@akdemirc
Thanks for your kind reply. Sorry for not being clear with my question. Im not considering the case when map is empty it ll be handled separately.
The following code will excutes fine.

void fn(map<string, string> &m, map<string, string>::iterator i) {
    cout << "i->first: " << i->first << endl;
    if (++i == m.end()) {
        end();
    } else {
        // call(bind(&fn, m, i));
        fn(m, i);
    }
}
int main() {
    map<string, string> m;
    m["abc"] = "asasd";
    m["bcd"] = "sasas";
    m["cde"] = "jdssd";
 
    // call(bind(&fn, m, m.begin()));
    fn(m, m.begin());
}
 

But with callbacks why am I getting a segmentation fault?