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meta.hpp/headers/meta.hpp/meta_uvalue.hpp
2023-01-18 02:58:06 +07:00

135 lines
4.9 KiB
C++

/*******************************************************************************
* This file is part of the "https://github.com/blackmatov/meta.hpp"
* For conditions of distribution and use, see copyright notice in LICENSE.md
* Copyright (C) 2021-2023, by Matvey Cherevko (blackmatov@gmail.com)
******************************************************************************/
#pragma once
#include "meta_base.hpp"
#include "meta_types.hpp"
namespace meta_hpp::detail
{
template < typename T >
concept uvalue_kind
= std::is_same_v<T, uvalue>;
template < typename T >
concept any_uvalue_kind =
std::is_same_v<T, uarg_base> ||
std::is_same_v<T, uarg> ||
std::is_same_v<T, uinst_base> ||
std::is_same_v<T, uinst> ||
std::is_same_v<T, uvalue>;
}
namespace meta_hpp
{
class uvalue final {
public:
uvalue() = default;
~uvalue();
uvalue(uvalue&& other) noexcept;
uvalue(const uvalue& other);
uvalue& operator=(uvalue&& other) noexcept;
uvalue& operator=(const uvalue& other);
template < typename T, typename Tp = std::decay_t<T> >
requires (!detail::any_uvalue_kind<Tp>)
&& (!detail::is_in_place_type_v<Tp>)
&& (std::is_copy_constructible_v<Tp>)
// NOLINTNEXTLINE(*-forwarding-reference-overload)
uvalue(T&& val);
template < typename T, typename Tp = std::decay_t<T> >
requires (!detail::any_uvalue_kind<Tp>)
&& (!detail::is_in_place_type_v<Tp>)
&& (std::is_copy_constructible_v<Tp>)
uvalue& operator=(T&& val);
template < typename T, typename... Args, typename Tp = std::decay_t<T> >
requires std::is_copy_constructible_v<Tp>
&& std::is_constructible_v<Tp, Args...>
explicit uvalue(std::in_place_type_t<T>, Args&&... args);
template < typename T, typename U, typename... Args, typename Tp = std::decay_t<T> >
requires std::is_copy_constructible_v<Tp>
&& std::is_constructible_v<Tp, std::initializer_list<U>&, Args...>
explicit uvalue(std::in_place_type_t<T>, std::initializer_list<U> ilist, Args&&... args);
template < typename T, typename... Args, typename Tp = std::decay_t<T> >
requires std::is_copy_constructible_v<Tp>
&& std::is_constructible_v<Tp, Args...>
std::decay_t<T>& emplace(Args&&... args);
template < typename T, typename U, typename... Args, typename Tp = std::decay_t<T> >
requires std::is_copy_constructible_v<Tp>
&& std::is_constructible_v<Tp, std::initializer_list<U>&, Args...>
std::decay_t<T>& emplace(std::initializer_list<U> ilist, Args&&... args);
[[nodiscard]] bool is_valid() const noexcept;
[[nodiscard]] explicit operator bool() const noexcept;
void reset();
void swap(uvalue& other) noexcept;
[[nodiscard]] const any_type& get_type() const noexcept;
[[nodiscard]] void* get_data() noexcept;
[[nodiscard]] const void* get_data() const noexcept;
[[nodiscard]] const void* get_cdata() const noexcept;
[[nodiscard]] uvalue operator*() const;
[[nodiscard]] bool has_deref_op() const noexcept;
[[nodiscard]] uvalue operator[](std::size_t index) const;
[[nodiscard]] bool has_index_op() const noexcept;
template < typename T >
[[nodiscard]] T get_as() &&;
template < typename T >
[[nodiscard]] auto get_as() &
-> std::conditional_t<detail::pointer_kind<T>, T, T&>;
template < typename T >
[[nodiscard]] auto get_as() const &
-> std::conditional_t<detail::pointer_kind<T>, T, const T&>;
template < typename T >
[[nodiscard]] auto try_get_as() noexcept
-> std::conditional_t<detail::pointer_kind<T>, T, T*>;
template < typename T >
[[nodiscard]] auto try_get_as() const noexcept
-> std::conditional_t<detail::pointer_kind<T>, T, const T*>;
private:
struct vtable_t;
vtable_t* vtable_{};
private:
struct buffer_t final {
// NOLINTNEXTLINE(*-avoid-c-arrays)
alignas(std::max_align_t) std::byte data[sizeof(void*) * 2];
};
using storage_u = std::variant<std::monostate, void*, buffer_t>;
storage_u storage_{};
};
inline void swap(uvalue& l, uvalue& r) noexcept {
l.swap(r);
}
template < typename T, typename... Args >
uvalue make_uvalue(Args&&... args) {
return uvalue(std::in_place_type<T>, std::forward<Args>(args)...);
}
template < typename T, typename U, typename... Args >
uvalue make_uvalue(std::initializer_list<U> ilist, Args&&... args) {
return uvalue(std::in_place_type<T>, ilist, std::forward<Args>(args)...);
}
}