Range-v3 Range algorithms, views, and actions for the Standard Library |

Public Types | Public Member Functions | List of all members
ranges::optional< T > Struct Template Reference
Inheritance diagram for ranges::optional< T >:

## Public Types
using | value_type = meta::_t< std::remove_cv< T > >

## Public Member Functions
template<typename... Args> requires constructible_from<T, Args...>
T & | emplace (Args &&... args) noexcept(std::is_nothrow_constructible< T, Args... >::value)
template<typename E , typename... Args> requires constructible_from<T, std::initializer_list<E> &, Args...>
T & | emplace (std::initializer_list< E > il, Args &&... args) noexcept(std::is_nothrow_constructible< T, std::initializer_list< E > &, Args... >::value)
template<typename I > requires constructible_from<T, decltype(*std::declval<const I &>())>
T & | emplace_deref (const I &it)
constexpr | operator bool () const noexcept
constexpr optional & | operator= (nullopt_t) noexcept
optional & | operator= (optional &&)=default
optional & | operator= (optional const &)=default
template<typename U > requires optional_should_convert_assign<U, T> && constructible_from<T, U> && assignable_from<T &, U>
constexpr optional & | operator= (optional< U > &&that)
template<typename U > requires optional_should_convert_assign<U, T> && constructible_from<T, const U &> && assignable_from<T &, const U &>
constexpr optional & | operator= (optional< U > const &that)
template<typename U = T> requires (!same_as<optional, detail::decay_t<U>>) && (!(satisfies<T, std::is_scalar> && same_as<T, detail::decay_t<U>>)) && constructible_from<T, U> && assignable_from<T &, U>
constexpr optional & | operator= (U &&u) noexcept(std::is_nothrow_constructible< T, U >::value &&std::is_nothrow_assignable< T &, U >::value)
template<typename E , typename... Args> requires constructible_from<T, std::initializer_list<E> &, Args...>
constexpr | optional (in_place_t, std::initializer_list< E > il, Args &&... args) noexcept(std::is_nothrow_constructible< T, std::initializer_list< E > &, Args... >::value)
constexpr | optional (nullopt_t) noexcept
| optional (optional &&)=default
| optional (optional const &)=default
template<typename U > requires optional_should_convert<U, T> && constructible_from<T, U> && convertible_to<U, T>
| optional (optional< U > &&that)
template<typename U > requires optional_should_convert<U, T> && constructible_from<T, U> && (!convertible_to<U, T>)
| optional (optional< U > &&that)
template<typename U > requires optional_should_convert<U, T> && constructible_from<T, U const &> && convertible_to<U const &, T>
| optional (optional< U > const &that)
template<typename U > requires optional_should_convert<U, T> && constructible_from<T, U const &> && (!convertible_to<U const &, T>)
| optional (optional< U > const &that)
template<typename U = T> requires (!same_as<detail::decay_t<U>, in_place_t>) && (!same_as<detail::decay_t<U>, optional>) && constructible_from<T, U> && convertible_to<U, T>
constexpr | optional (U &&v)
template<typename U = T> requires (!same_as<detail::decay_t<U>, in_place_t>) && (!same_as<detail::decay_t<U>, optional>) && constructible_from<T, U> && (!convertible_to<U, T>)
constexpr | optional (U &&v)
constexpr T & | value () &
constexpr T && | value () &&
constexpr T const & | value () const &
constexpr T const && | value () const &&
template<typename U > requires move_constructible<T> && convertible_to<U, T>
constexpr T | value_or (U &&u) &&
template<typename U > requires copy_constructible<T> && convertible_to<U, T>
constexpr T | value_or (U &&u) const &