Hands-On Design Patterns with C++

Generic ScopeGuard

We are now firmly in C++11 territory, nothing that you are about to see has a C++03 equivalent of any practical worth.

Our ScopeGuard has, so far, allowed us to all arbitrary functions as rollback for any action. Just like the hand-crafted guard objects, the scope guards are composable and guarantee exception safety. But our implementation, so far, is somewhat limited in what exactly we can call to implement the rollback; it has to be a function or a member function. While this seems to cover a lot, we may want to call, for example, two functions to do a single rollback. We could, of course, write a wrapper function for that, but that sets us back on the path toward single-purpose hand-crafted rollback objects.

There ...