std::optional<T>::end

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std::optional

Member functions
optional::optional
optional::~optional
optional::operator=
Observers
optional::operator->optional::operator*
optional::operator booloptional::has_value
optional::value
optional::value_or
Iterators
optional::begin (C++26)
optional::end (C++26)
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optional::and_then (C++23)
optional::transform (C++23)
optional::or_else (C++23)
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optional::emplace
optional::swap
optional::reset
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operator==operator!=operator<operator<=operator>operator>=operator<=> (C++20)
make_optional
swap(std::optional)
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hash<std::optional>
nullopt_t
in_place_t
bad_optional_access
Helper objects
nullopt
in_place

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constexpr iterator end()noexcept;		(since C++26)
constexpr const_iterator end()constnoexcept;		(since C++26)

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

[edit]Return value

Past-the-end iterator

[edit]Complexity

Constant.

[edit]Notes

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

[edit]Example

Run this code

#include <optional>#include <print> int main(){constexprstd::optional<int> none{std::nullopt};// optional @1constexprstd::optional<int> some{42};// optional @2     static_assert(none.begin()== none.end());    static_assert(some.begin()!= some.end()); // ranged-for loop supportfor(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);}