STD::OPTIONAL(3cxx)

🌸 NAME 🌸

okay so welcome to std::optional< _Tp > bestie — it's a class template for optional values. 💖 And yes, this is the std::optional< _Tp >(3cxx) page, we're here, we're doing it, let's go. 🦋

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✨ SYNOPSIS ✨

#include <optional>

Also important: it inherits std::_Optional_base< _Tp, bool, bool >. Family tree matters, periodt. 👑

🌈 Public Types

• using value_type — that's it, that's the type. iconic.

💅 Public Member Functions

okay this is the long part, grab a snack 🍓 — every single one, no skipping:

• template<typename _Up = _Tp, _Requires< __not_self< _Up >, __not_tag< _Up >, is_constructible< _Tp, _Up >, __not_< is_convertible< _Up, _Tp > > > = false> constexpr optional (_Up &&__t) noexcept(is_nothrow_constructible_v< _Tp, _Up >)
• template<typename _Up = _Tp, _Requires< __not_self< _Up >, __not_tag< _Up >, is_constructible< _Tp, _Up >, is_convertible< _Up, _Tp > > = true> constexpr optional (_Up &&__t) noexcept(is_nothrow_constructible_v< _Tp, _Up >)
• template<typename _Up, _Requires< __not_< is_same< _Tp, _Up > >, is_constructible< _Tp, const _Up & >, __not_< is_convertible< const _Up &, _Tp > >, __not_< __converts_from_optional< _Tp, _Up > > > = false> constexpr optional (const optional< _Up > &__t) noexcept(is_nothrow_constructible_v< _Tp, const _Up & >)
• template<typename _Up, _Requires< __not_< is_same< _Tp, _Up > >, is_constructible< _Tp, const _Up & >, is_convertible< const _Up &, _Tp >, __not_< __converts_from_optional< _Tp, _Up > > > = true> constexpr optional (const optional< _Up > &__t) noexcept(is_nothrow_constructible_v< _Tp, const _Up & >)
• template<typename... _Args, _Requires< is_constructible< _Tp, _Args... > > = false> constexpr optional (in_place_t, _Args &&... __args) noexcept(is_nothrow_constructible_v< _Tp, _Args... >)
• template<typename _Up, typename... _Args, _Requires< is_constructible< _Tp, initializer_list< _Up > &, _Args... > > = false> constexpr optional (in_place_t, initializer_list< _Up > __il, _Args &&... __args) noexcept(is_nothrow_constructible_v< _Tp, initializer_list< _Up > &, _Args... >)
• constexpr optional (nullopt_t) noexcept
• template<typename _Up, _Requires< __not_< is_same< _Tp, _Up > >, is_constructible< _Tp, _Up >, __not_< is_convertible< _Up, _Tp > >, __not_< __converts_from_optional< _Tp, _Up > > > = false> constexpr optional (optional< _Up > &&__t) noexcept(is_nothrow_constructible_v< _Tp, _Up >)
• template<typename _Up, _Requires< __not_< is_same< _Tp, _Up > >, is_constructible< _Tp, _Up >, is_convertible< _Up, _Tp >, __not_< __converts_from_optional< _Tp, _Up > > > = true> constexpr optional (optional< _Up > &&__t) noexcept(is_nothrow_constructible_v< _Tp, _Up >)
• template<typename... _Args> constexpr enable_if_t< is_constructible_v< _Tp, _Args... >, _Tp & > emplace (_Args &&... __args) noexcept(is_nothrow_constructible_v< _Tp, _Args... >)
• template<typename _Up, typename... _Args> constexpr enable_if_t< is_constructible_v< _Tp, initializer_list< _Up > &, _Args... >, _Tp & > emplace (initializer_list< _Up > __il, _Args &&... __args) noexcept(is_nothrow_constructible_v< _Tp, initializer_list< _Up > &, _Args... >)
• constexpr bool has_value () const noexcept
• constexpr operator bool () const noexcept
• constexpr _Tp && operator* () &&noexcept
• constexpr _Tp & operator* () &noexcept
• constexpr const _Tp && operator* () const &&noexcept
• constexpr const _Tp & operator* () const &noexcept
• constexpr const _Tp * operator-> () const noexcept
• constexpr _Tp * operator-> () noexcept
• template<typename _Up = _Tp> constexpr enable_if_t< __and_v< __not_self< _Up >, __not_< __and_< is_scalar< _Tp >, is_same< _Tp, decay_t< _Up > > > >, is_constructible< _Tp, _Up >, is_assignable< _Tp &, _Up > >, optional & > operator= (_Up &&__u) noexcept(__and_v< is_nothrow_constructible< _Tp, _Up >, is_nothrow_assignable< _Tp &, _Up > >)
• template<typename _Up> constexpr enable_if_t< __and_v< __not_< is_same< _Tp, _Up > >, is_constructible< _Tp, const _Up & >, is_assignable< _Tp &, const _Up & >, __not_< __converts_from_optional< _Tp, _Up > >, __not_< __assigns_from_optional< _Tp, _Up > > >, optional & > operator= (const optional< _Up > &__u) noexcept(__and_v< is_nothrow_constructible< _Tp, const _Up & >, is_nothrow_assignable< _Tp &, const _Up & > >)
• constexpr optional & operator= (nullopt_t) noexcept
• template<typename _Up> constexpr enable_if_t< __and_v< __not_< is_same< _Tp, _Up > >, is_constructible< _Tp, _Up >, is_assignable< _Tp &, _Up >, __not_< __converts_from_optional< _Tp, _Up > >, __not_< __assigns_from_optional< _Tp, _Up > > >, optional & > operator= (optional< _Up > &&__u) noexcept(__and_v< is_nothrow_constructible< _Tp, _Up >, is_nothrow_assignable< _Tp &, _Up > >)
• constexpr void reset () noexcept
• constexpr void swap (optional &__other) noexcept(is_nothrow_move_constructible_v< _Tp > &&is_nothrow_swappable_v< _Tp >)
• constexpr _Tp & value () &
• constexpr _Tp && value () &&
• constexpr const _Tp & value () const &
• constexpr const _Tp && value () const &&
• template<typename _Up> constexpr _Tp value_or (_Up &&__u) &&
• template<typename _Up> constexpr _Tp value_or (_Up &&__u) const &

no cap, that's the whole roster. copy them exactly, bestie, do not freestyle the template params. 😭

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💖 Detailed Description 💖

template<typename _Tp>
class std::optional< _Tp >

"Class template for optional values." — literally the whole detailed description, and honestly? it ate. 🌟

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🫶 Author 🫶

Generated automatically by Doxygen for libstdc++ from the source code. so like, no human author to thank, it's a robot doing the most. 🙈

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and that's the page!! 💜 shoutout to libstdc++ for the source and to this lil manpage's home in section 3cxx — that's where you'll find it, iykyk. go forth and emplace responsibly. 💅✨