C++ - Performance when declaring enum outside or in class?

Question

I have a pretty concrete question; Is there any difference in the performance when declaring an enum outside a class and when declaring an enum within the class? Thanks!

Answer 1

No, there is no performance difference.

Any enum or enum class declared within class scope has it's name bounded to the class' name (in the sense that the name of a class is also a namespace); and access checking is performed for its use.

The only real difference here is the access checking, otherwise, the namespace point, is not an issue, because every name in C++ is decared within some namespace (whether global or not).

There is no performance implication.