Meyer's implementation (with static block variable) is elegant and thread safe, and retains lazy initialization which can be important for the initialization or

Meyer's implementation (with static block variable) is elegant and thread safe, and retains lazy initialization which can be important for the initialization order. https://www.modernescpp.com/index.php/thread-safe-initialization-of-data/ https://www.modernescpp.com/index.php/thread-safe-initializa...