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// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/types/pass_key.h"
#include <concepts>
#include <utility>
namespace base {
namespace {
class Manager;
// May not be created without a PassKey.
class Restricted {
public:
explicit Restricted(base::PassKey<Manager>) {}
};
Restricted ConstructWithCopiedPassKey(base::PassKey<Manager> key) {
return Restricted(key);
}
Restricted ConstructWithMovedPassKey(base::PassKey<Manager> key) {
return Restricted(std::move(key));
}
class Manager {
public:
enum class ExplicitConstruction { kTag };
enum class UniformInitialization { kTag };
enum class CopiedKey { kTag };
enum class MovedKey { kTag };
explicit Manager(ExplicitConstruction)
: restricted_(base::PassKey<Manager>()) {}
explicit Manager(UniformInitialization) : restricted_({}) {}
explicit Manager(CopiedKey) : restricted_(ConstructWithCopiedPassKey({})) {}
explicit Manager(MovedKey) : restricted_(ConstructWithMovedPassKey({})) {}
private:
Restricted restricted_;
};
static_assert(std::constructible_from<Manager, Manager::ExplicitConstruction>);
static_assert(std::constructible_from<Manager, Manager::UniformInitialization>);
static_assert(std::constructible_from<Manager, Manager::CopiedKey>);
static_assert(std::constructible_from<Manager, Manager::MovedKey>);
} // namespace
} // namespace base
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