RMUL2025/lib/magic_enum/include/magic_enum_fuse.hpp

90 lines
3.7 KiB
C++

// __ __ _ ______ _____
// | \/ | (_) | ____| / ____|_ _
// | \ / | __ _ __ _ _ ___ | |__ _ __ _ _ _ __ ___ | | _| |_ _| |_
// | |\/| |/ _` |/ _` | |/ __| | __| | '_ \| | | | '_ ` _ \ | | |_ _|_ _|
// | | | | (_| | (_| | | (__ | |____| | | | |_| | | | | | | | |____|_| |_|
// |_| |_|\__,_|\__, |_|\___| |______|_| |_|\__,_|_| |_| |_| \_____|
// __/ | https://github.com/Neargye/magic_enum
// |___/ version 0.8.1
//
// Licensed under the MIT License <http://opensource.org/licenses/MIT>.
// SPDX-License-Identifier: MIT
// Copyright (c) 2019 - 2022 Daniil Goncharov <neargye@gmail.com>.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
#ifndef NEARGYE_MAGIC_ENUM_FUSE_HPP
#define NEARGYE_MAGIC_ENUM_FUSE_HPP
#include "magic_enum.hpp"
namespace magic_enum {
namespace detail {
template <typename E>
constexpr optional<std::uintmax_t> fuse_one_enum(optional<std::uintmax_t> hash, E value) noexcept {
if (hash) {
if (const auto index = enum_index(value)) {
return (*hash << log2(enum_count<E>() + 1)) | *index;
}
}
return {};
}
template <typename E>
constexpr optional<std::uintmax_t> fuse_enum(E value) noexcept {
return fuse_one_enum(0, value);
}
template <typename E, typename... Es>
constexpr optional<std::uintmax_t> fuse_enum(E head, Es... tail) noexcept {
return fuse_one_enum(fuse_enum(tail...), head);
}
template <typename... Es>
constexpr auto typesafe_fuse_enum(Es... values) noexcept {
enum class enum_fuse_t : std::uintmax_t;
const auto fuse = fuse_enum(values...);
if (fuse) {
return optional<enum_fuse_t>{static_cast<enum_fuse_t>(*fuse)};
}
return optional<enum_fuse_t>{};
}
} // namespace magic_enum::detail
// Returns a bijective mix of several enum values. This can be used to emulate 2D switch/case statements.
template <typename... Es>
[[nodiscard]] constexpr auto enum_fuse(Es... values) noexcept {
static_assert((std::is_enum_v<std::decay_t<Es>> && ...), "magic_enum::enum_fuse requires enum type.");
static_assert(sizeof...(Es) >= 2, "magic_enum::enum_fuse requires at least 2 values.");
static_assert((detail::log2(enum_count<std::decay_t<Es>>() + 1) + ...) <= (sizeof(std::uintmax_t) * 8), "magic_enum::enum_fuse does not work for large enums");
#if defined(MAGIC_ENUM_NO_TYPESAFE_ENUM_FUSE)
const auto fuse = detail::fuse_enum<std::decay_t<Es>...>(values...);
#else
const auto fuse = detail::typesafe_fuse_enum<std::decay_t<Es>...>(values...);
#endif
return assert(fuse), fuse;
}
} // namespace magic_enum
#endif // NEARGYE_MAGIC_ENUM_FUSE_HPP