> unique_ptr is pretty bad for performance as well.
Do you mean in terms of cache locality because it's heap-allocated instead of stack-allocated, or are you actually commenting on the overhead of copying some extra ints and invoking the destructor?
Because it's certainly correct that just because you can use a unique_ptr, doesn't mean you should. ("A std::unique_ptr is used for expressing transfer of ownership. If you never pass ownership elsewhere, the std::unique_ptr abstraction is rarely necessary or appropriate." - https://abseil.io/tips/187)
Safety is a good reason. I like protection against leaks and use after free. If I’m already allocating I’m not going to worry about the little bit of extra performance cost the abstraction might have.
To be clear: I'm not advocating for the use of `new` / `delete` over unique_ptr. But if you're creating a local object that never has to leave the current scope (or a member variable that's never moved in or out), there's no benefit to using a unique_ptr instead of creating the object directly on the stack or inline as part of your class, where the object's lifetime is bound to the scope, and your destructor is automatically run when its containing scope is cleaned up.
As an added bonus, you don't actually have to do a separate heap allocation.
I agree! You should use a regular object if possible, I’d never suggest otherwise. The rare exceptions I’ve run into are annoying initialization order issues (usually code that I didn’t have the time/knowledge/political credits to refactor) and large arrays that blow the stack.
Do you mean in terms of cache locality because it's heap-allocated instead of stack-allocated, or are you actually commenting on the overhead of copying some extra ints and invoking the destructor?
Because it's certainly correct that just because you can use a unique_ptr, doesn't mean you should. ("A std::unique_ptr is used for expressing transfer of ownership. If you never pass ownership elsewhere, the std::unique_ptr abstraction is rarely necessary or appropriate." - https://abseil.io/tips/187)