ms-gsl

Below is excerpted from gsl.h of Microsoft's gsl library ( https://github.com/microsoft/gsl ): namespace gsl { // // GSL.owner: ownership pointers // using std::unique_ptr; using std::shared_ptr; template<class T> using owner = T; ... }; I cannot understand what the following alias template means: template<class T> using owner = T; Any explanations? It means that for every T , owner<T> is an alias for T . It can be used as annotation to show which pointers are 'owner' ie: Example of non owning raw pointer template<typename T> class X2 { // ... public: owner<T*> p; // OK: p is owning T* q; //