std::filesystem::begin(directory_iterator), std::filesystem::end(directory_iterator)

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std::filesystem::directory_iterator
Member functions
Non-member functions
begin(std::filesystem::directory_iterator)end(std::filesystem::directory_iterator)
 
Defined in header <filesystem>
directory_iterator begin( directory_iterator iter ) noexcept;
(1) (since C++17)
directory_iterator end( directory_iterator ) noexcept;
(2) (since C++17)
1) Returns iter unchanged.
2) Returns a default-constructed directory_iterator, which serves as the end iterator. The argument is ignored.

These non-member functions enable the use of directory_iterators with range-based for loops and make directory_iterator a range type(since C++20).

Parameters

iter - a directory_iterator

Return value

1) iter unchanged.
2) End iterator (default-constructed directory_iterator).

Example

#include <filesystem>
#include <fstream>
#include <iostream>
namespace fs = std::filesystem;
 
int main()
{
    fs::create_directories("sandbox/a/b");
    std::ofstream("sandbox/file1.txt");
    std::ofstream("sandbox/file2.txt");
    for (auto& p : fs::directory_iterator("sandbox"))
        std::cout << p << '\n';
    fs::remove_all("sandbox");
}

Possible output:

"sandbox/a"
"sandbox/file1.txt"
"sandbox/file2.txt"

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR Applied to Behavior as published Correct behavior
LWG 3480 C++17 end took the argument by reference takes the argument by value

See also

range-based for loop support
(function)