DART  6.7.3
Singleton-impl.hpp
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32 
33 #ifndef DART_COMMON_DETAIL_SINGLETON_HPP_
34 #define DART_COMMON_DETAIL_SINGLETON_HPP_
35 
37 
38 #include <utility>
39 
40 namespace dart {
41 namespace common {
42 
43 //==============================================================================
44 template <typename T> T* Singleton<T>::mInstance = nullptr;
45 
46 //==============================================================================
47 template <typename T>
48 template <typename... Args>
49 T& Singleton<T>::getSingleton(Args... _args)
50 {
51  // http://stackoverflow.com/questions/1008019/c-singleton-design-pattern
52 
53  // Guaranteed to be destroyed and instantiated on first use.
54  if (mInstance == nullptr)
55  {
56  static T instance(std::forward<Args>(_args)...);
57  mInstance = &instance;
58  }
59 
60  return *mInstance;
61 }
62 
63 //==============================================================================
64 template <typename T>
65 template <typename ... Args>
67 {
68  return &getSingleton(std::forward<Args>(_args)...);
69 }
70 
71 } // namespace common
72 } // namespace dart
73 
74 #endif // DART_COMMON_DETAIL_SINGLETON_HPP_
static T * mInstance
Singleton instance.
Definition: Singleton.hpp:77
static T * getSingletonPtr(Args... _args)
Returns pointer of the singleton.
Definition: Singleton-impl.hpp:66
static T & getSingleton(Args... _args)
Returns reference of the singleton.
Definition: Singleton-impl.hpp:49
Definition: BulletCollisionDetector.cpp:63