MeyerSingleton.hpp

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/*
 
  This file is part of OpenFLUID software
  Copyright(c) 2021-2026, INRAE
 
 
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 == Other Usage ==
 
  Other Usage means a use of OpenFLUID that is inconsistent with the GPL
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*/
 
/**
  @file MeyerSingleton.hpp
 
  @author Jean-Christophe FABRE <jean-christophe.fabre@inra.fr>
*/
 
 
#ifndef __OPENFLUID_UTILS_MEYERSINGLETON_HPP__
#define __OPENFLUID_UTILS_MEYERSINGLETON_HPP__
 
 
namespace openfluid { namespace utils {
 
 
/**
  Singleton template class implementing the Meyer's singleton design.
  This implementation is thread safe in C++11.
 
  @warning This template class does not work in a cross-dll context on Windows.
  Due to this restriction, it must not be used in the OpenFLUID framework.
 
  Example of use to design an Example class as a singleton
  @snippet misc/singleton.cpp meyersingleton
*/
template<typename T>
class MeyerSingleton
{
 
  private:
 
    MeyerSingleton<T>(T const&) = delete;
 
    void operator=(T const&) = delete;
 
 
  protected:
 
    MeyerSingleton<T>() = default;
 
 
  public:
 
 
    /**
      Returns a pointer to the singleton object.
      Instantiates the class if it not has not been instantiated before.
      @return A pointer to the singleton object
    */
    static T* instance()
    {
       static T m_Instance;
       return &m_Instance;
    }
};
 
 
} }  // namespaces
 
 
#endif /* __OPENFLUID_UTILS_MEYERSINGLETON_HPP__ */