That fail class has major problems that are probably not obvious to those unfamiliar with C++. It breaks the rule of three [1]. It cannot be safely copied, and

That fail class has major problems that are probably not obvious to those unfamiliar with C++. It breaks the rule of three [1]. It cannot be safely copied, and you haven't disabled the copy-constructor or assignment operator, which makes it super-dangerous. [1] https://en.wikipedia.org/wiki/Rule_of_three_%28C%2B%2B_programming%29 https://en.wikipedia.org/wiki/Rule_of_three_%28C%2B%2B_progr...