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#pragma once
#include "asl/status.hpp"
#include "asl/maybe_uninit.hpp"
#include "asl/hash.hpp"
namespace asl
{
template<is_object T>
class status_or
{
status m_status;
maybe_uninit<T> m_value{};
public:
// @Todo Convert copy
// @Todo Convert move
constexpr status_or(const status_or& other)
requires copy_constructible<T>
: m_status{other.m_status}
{
if (other.ok())
{
m_value.construct_unsafe(other.m_value.as_init_unsafe());
}
}
constexpr status_or(status_or&& other)
requires move_constructible<T>
: m_status{ASL_MOVE(other.m_status)}
{
if (other.ok())
{
m_value.construct_unsafe(ASL_MOVE(other.m_value.as_init_unsafe()));
}
}
constexpr status_or& operator=(const status_or& other)
requires copyable<T>
{
if (&other != this)
{
if (ok())
{
if (other.ok())
{
m_value.assign_unsafe(other.m_value.as_init_unsafe());
}
else
{
m_value.destroy_unsafe();
}
}
else if (other.ok())
{
m_value.construct_unsafe(other.m_value.as_init_unsafe());
}
m_status = other.m_status;
}
return *this;
}
constexpr status_or& operator=(status_or&& other)
requires moveable<T>
{
if (&other != this)
{
if (ok())
{
if (other.ok())
{
m_value.assign_unsafe(ASL_MOVE(other.m_value.as_init_unsafe()));
}
else
{
m_value.destroy_unsafe();
}
}
else if (other.ok())
{
m_value.construct_unsafe(ASL_MOVE(other.m_value.as_init_unsafe()));
}
m_status = ASL_MOVE(other.m_status);
}
return *this;
}
constexpr ~status_or()
{
if (m_status.ok())
{
m_value.destroy_unsafe();
}
}
// NOLINTNEXTLINE(*-explicit-conversions)
constexpr status_or(const status& status) : m_status{status}
{
ASL_ASSERT_RELEASE(!m_status.ok());
}
// NOLINTNEXTLINE(*-explicit-conversions)
constexpr status_or(status&& status) : m_status{ASL_MOVE(status)}
{
ASL_ASSERT_RELEASE(!m_status.ok());
}
status_or& operator=(status status) = delete;
template<typename U = T>
constexpr explicit (!convertible_from<T, U&&>)
status_or(U&& value)
requires (
constructible_from<T, U&&> &&
!same_as<un_cvref_t<U>, status_or> &&
!same_as<un_cvref_t<U>, status>
)
: m_status{status_code::ok}
, m_value{in_place, ASL_FWD(value)}
{}
constexpr bool ok() const { return m_status.ok(); }
constexpr status_code code() const { return m_status.code(); }
constexpr string_view message() const { return m_status.message(); }
constexpr status&& throw_status() && { return ASL_MOVE(m_status); }
// @Todo(C++23) Deducing this
constexpr const T& value() const&
{
ASL_ASSERT_RELEASE(ok());
return m_value.as_init_unsafe();
}
constexpr T& value() &
{
ASL_ASSERT_RELEASE(ok());
return m_value.as_init_unsafe();
}
constexpr T&& value() &&
{
ASL_ASSERT_RELEASE(ok());
return ASL_MOVE(m_value.as_init_unsafe());
}
template<typename U>
constexpr T value_or(U&& other_value) const&
requires copy_constructible<T> && convertible_from<T, U&&>
{
return ok() ? value() : static_cast<T>(ASL_FWD(other_value));
}
template<typename U>
constexpr T value_or(U&& other_value) &&
requires move_constructible<T> && convertible_from<T, U&&>
{
return ok() ? ASL_MOVE(value()) : static_cast<T>(ASL_FWD(other_value));
}
friend void AslFormat(Formatter& f, const status_or& status)
{
AslFormat(f, status.m_status);
}
template<typename H>
requires hashable<T>
friend H AslHashValue(H h, const status_or& s)
{
if (s.ok())
{
return H::combine(ASL_MOVE(h), s.m_status, s.value());
}
return H::combine(ASL_MOVE(h), s.m_status);
}
};
template<typename T>
status_or(T) -> status_or<T>;
} // namespace asl
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