yuzu/src/common/unique_function.h

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// SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later
2021-04-01 05:03:25 +01:00
#pragma once
#include <memory>
#include <utility>
namespace Common {
/// General purpose function wrapper similar to std::function.
/// Unlike std::function, the captured values don't have to be copyable.
/// This class can be moved but not copied.
template <typename ResultType, typename... Args>
class UniqueFunction {
class CallableBase {
public:
virtual ~CallableBase() = default;
virtual ResultType operator()(Args&&...) = 0;
};
template <typename Functor>
class Callable final : public CallableBase {
public:
Callable(Functor&& functor_) : functor{std::move(functor_)} {}
~Callable() override = default;
ResultType operator()(Args&&... args) override {
return functor(std::forward<Args>(args)...);
}
private:
Functor functor;
};
public:
UniqueFunction() = default;
template <typename Functor>
UniqueFunction(Functor&& functor)
: callable{std::make_unique<Callable<Functor>>(std::move(functor))} {}
UniqueFunction& operator=(UniqueFunction&& rhs) noexcept = default;
UniqueFunction(UniqueFunction&& rhs) noexcept = default;
UniqueFunction& operator=(const UniqueFunction&) = delete;
UniqueFunction(const UniqueFunction&) = delete;
ResultType operator()(Args&&... args) const {
return (*callable)(std::forward<Args>(args)...);
}
explicit operator bool() const noexcept {
return static_cast<bool>(callable);
}
private:
std::unique_ptr<CallableBase> callable;
};
} // namespace Common