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#pragma once
#include <type_traits>
#include <concepts>
namespace floormat::Pack {
template<std::unsigned_integral T, uint8_t N> struct Bits_;
} // namespace floormat::Pack
namespace floormat::detail_Pack {
using namespace floormat::Pack;
template<std::unsigned_integral T, size_t Sum, typename... Xs> struct check_size_overflow;
template<std::unsigned_integral T, std::unsigned_integral U, size_t Sum, uint8_t N, typename... Xs>
struct check_size_overflow<T, Sum, Bits_<U, N>, Xs...>
{
static_assert(std::is_same_v<T, U>);
static constexpr auto acc = Sum + size_t{N};
using next_check = check_size_overflow<T, acc, Xs...>;
static constexpr auto size = next_check::size;
static constexpr bool result = next_check::result;
};
template<std::unsigned_integral T, size_t Sum>
struct check_size_overflow<T, Sum>
{
static constexpr size_t size = Sum;
static constexpr bool result = Sum <= sizeof(T)*8;
};
template<std::unsigned_integral T, size_t CAPACITY>
struct Storage
{
static_assert(CAPACITY <= sizeof(T)*8);
static constexpr size_t Capacity = CAPACITY;
T value;
template<size_t N>
constexpr T get() const
{
static_assert(N <= sizeof(T)*8);
static_assert(N <= Capacity);
return T(value & (T(1) << N) - T(1));
}
template<size_t N>
constexpr T advance() const
{
static_assert(N <= sizeof(T)*8);
static_assert(N <= Capacity);
return T(value >> N);
}
constexpr bool operator==(const Storage&) const noexcept = default;
constexpr bool check_zero() const = delete;
template<size_t N> using next = Storage<T, Capacity - N>;
};
template<std::unsigned_integral T>
struct Storage<T, 0>
{
static constexpr size_t Capacity = 0;
T value;
template<size_t N> [[maybe_unused]] constexpr T get() const = delete;
template<size_t N> [[maybe_unused]] constexpr T advance() const = delete;
constexpr bool operator==(const Storage&) const noexcept = default;
[[nodiscard]] constexpr inline bool check_zero() const
{
return value == T(0);
}
template<size_t N> struct next
{
static_assert(!std::is_same_v<T, void>, "reading past the end");
static_assert( std::is_same_v<T, void>, "reading past the end");
};
};
} // namespace floormat::detail_Pack
namespace floormat::Pack {
template<std::unsigned_integral T, uint8_t N>
struct Bits_ final
{
static_assert(std::is_fundamental_v<T>);
static_assert(N > 0);
static_assert(N < sizeof(T)*8);
using type = T;
static constexpr auto bits = N;
};
} // namespace floormat::Pack
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