std::optional::end - cppreference.com (original) (raw)

| constexpr iterator end() noexcept; | | (since C++26) | | ----------------------------------------------- | | ------------- | | constexpr const_iterator end() const noexcept; | | (since C++26) |

Returns a past-the-end iterator. Equivalent to return begin() + has_value();.

[edit] Return value

Past-the-end iterator

[edit] Complexity

Constant.

[edit] Notes

[edit] Example

#include #include   int main() { constexpr std::optional none{std::nullopt}; // optional @1 constexpr std::optional some{42}; // optional @2   static_assert(none.begin() == none.end()); static_assert(some.begin() != some.end());   // ranged-for loop support for (int i : none) std::println("Optional @1 has a value of {}", i);   for (int i : some) std::println("Optional @2 has a value of {}", i); }

Output:

Optional @2 has a value of 42

[edit] See also

| | returns an iterator to the beginning (public member function) [edit] | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |