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#pragma once
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#include <memory>

            

        

            

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namespace Envoy {

            

        

            

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namespace Singleton {

            

        

            

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/**

            

        

            

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 * All singletons must derive from this type.

            

        

            

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 */

            

        

            

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class Instance {

            

        

            

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public:

            

        

            

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  virtual ~Instance() = default;

            

        

            

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};

            

        

            

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using InstanceSharedPtr = std::shared_ptr<Instance>;

            

        

            

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} // namespace Singleton

            

        

            

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} // namespace Envoy