Singleton.h

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*/

#pragma once

namespace prtx {


template<typename S>
class Singleton {
public:
    static S* instance() {
        if (!mInstance)
            mInstance = S::createInstance();
        return mInstance;
    }

protected:
    Singleton() = default;
    Singleton(const Singleton&) = delete;
    Singleton& operator=(const Singleton&) = delete;
    ~Singleton() = default;

private:
    static S* mInstance;
};

template<typename S> S* Singleton<S>::mInstance = nullptr;


} // namespace prtx