std::optional<T>::end

Since C++26

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

# Declarations

constexpr iterator end() noexcept;

(since C++26)

constexpr const_iterator end() const noexcept;

(since C++26)

# Return value

Past-the-end iterator

# Notes

Feature-test macro Value Std Feature __cpp_lib_optional_range_support 202406L (C++26) Range support for std::optional

# Example

#include <optional>
#include <print>
 
int main()
{
    constexpr std::optional<int> none = std::nullopt; // optional @1
    constexpr std::optional<int> 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);
}

# See also

begin