What is the reason of this error 'it' was not declared in this scope?

Asked Jun 05 '18 at 21:24

Active Jun 05 '18 at 21:33

Viewed 52 times

What is the reason of this error in this case?

'it' was not declared in this scope

I don't understand why I get that error, I defined it in statement of for loop..

#include <vector>
#include <iostream>
template<class T>
void LoopFunction() {
    std::vector<T> vec;
    for (std::vector<T>::iterator it = vec.begin(); it != vec.end(); it++) { // **error in this line**
        //....
    }
}

edited Jun 05 '18 at 21:33

asked Jun 05 '18 at 21:24

Software_t

1

Please **[edit]** your question with an [mcve] or [SSCCE (Short, Self Contained, Correct Example)](http://sscce.org) – NathanOliver Jun 05 '18 at 21:24
@NathanOliver What is not good with my question? I aksed exactly what is the problem.. – Software_t Jun 05 '18 at 21:26
5

`vector::iterator` Maybe you forgot to prefix it with `std::`? – Killzone Kid Jun 05 '18 at 21:27
4

@Software_t Your question is missing information. For instance, do you have a `using namespace std;` before this code? – NathanOliver Jun 05 '18 at 21:30
4

I'm wondering if it also requires `typename`, i.e. `for (typename std::vector::iterator it = vec.begin(); ...` – Fred Larson Jun 05 '18 at 21:31
@FredLarson it's working now! can you explain why please? – Software_t Jun 05 '18 at 21:32
1

[Dependent names](http://en.cppreference.com/w/cpp/language/dependent_name). – Fred Larson Jun 05 '18 at 21:33
3

Since you are using C++11, just write `for (auto it = vec.begin(); it != vec.end(); ++it) { ... }` or even better: `for (auto const& element : vec) { ... }` – Justin Jun 05 '18 at 21:36

What is the reason of this error 'it' was not declared in this scope?

0 Answers0