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/*
* Copyright 2019 The Chromium Authors. All rights reserved.
* Copyright (c) 2021 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef RTC_BASE_STRONG_ALIAS_H_
#define RTC_BASE_STRONG_ALIAS_H_
#include <type_traits>
#include <utility>
namespace webrtc {
// This is a copy of
// https://source.chromium.org/chromium/chromium/src/+/main:base/types/strong_alias.h
// as the API (and internals) are using type-safe integral identifiers, but this
// library can't depend on that file. The ostream operator has been removed
// per WebRTC library conventions, and the underlying type is exposed.
template <typename TagType, typename TheUnderlyingType>
class StrongAlias {
public:
using UnderlyingType = TheUnderlyingType;
constexpr StrongAlias() = default;
constexpr explicit StrongAlias(const UnderlyingType& v) : value_(v) {}
constexpr explicit StrongAlias(UnderlyingType&& v) noexcept
: value_(std::move(v)) {}
constexpr UnderlyingType* operator->() { return &value_; }
constexpr const UnderlyingType* operator->() const { return &value_; }
constexpr UnderlyingType& operator*() & { return value_; }
constexpr const UnderlyingType& operator*() const& { return value_; }
constexpr UnderlyingType&& operator*() && { return std::move(value_); }
constexpr const UnderlyingType&& operator*() const&& {
return std::move(value_);
}
constexpr UnderlyingType& value() & { return value_; }
constexpr const UnderlyingType& value() const& { return value_; }
constexpr UnderlyingType&& value() && { return std::move(value_); }
constexpr const UnderlyingType&& value() const&& { return std::move(value_); }
constexpr explicit operator const UnderlyingType&() const& { return value_; }
constexpr bool operator==(const StrongAlias& other) const {
return value_ == other.value_;
}
constexpr bool operator!=(const StrongAlias& other) const {
return value_ != other.value_;
}
constexpr bool operator<(const StrongAlias& other) const {
return value_ < other.value_;
}
constexpr bool operator<=(const StrongAlias& other) const {
return value_ <= other.value_;
}
constexpr bool operator>(const StrongAlias& other) const {
return value_ > other.value_;
}
constexpr bool operator>=(const StrongAlias& other) const {
return value_ >= other.value_;
}
protected:
UnderlyingType value_;
};
} // namespace webrtc
#endif // RTC_BASE_STRONG_ALIAS_H_