singleton.h

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#ifndef SINGA_UTILS_SINGLETON_H_
#define SINGA_UTILS_SINGLETON_H_

//  http://stackoverflow.com/questions/2576022/efficient-thread-safe-singleton-in-c
template<typename T>
class Singleton {
 public:
  static T* Instance() {
    static T data_;
    return &data_;
  }
};

/*
template<typename T>
class TSingleton {
 public:
  static T* Instance() {
    static thread_local T data_;  // thread_local is not available in some
                                  // compilers
    return &data_;
  }
};
*/

#endif  // SINGA_UTILS_SINGLETON_H_