Unnamed/anonymous namespaces vs. static functions

Question

A feature of C++ is the ability to create unnamed (anonymous) namespaces, like so:

namespace {
    int cannotAccessOutsideThisFile() { ... }
} // namespace
<         


        

Answer 1

Personally I prefer static functions over nameless namespaces for the following reasons:

• It's obvious and clear from function definition alone that it's private to the translation unit where it's compiled. With nameless namespace you might need to scroll and search to see if a function is in a namespace.

• Functions in namespaces might be treated as extern by some (older) compilers. In VS2017 they are still extern. For this reason even if a function is in nameless namespace you might still want to mark them static.

• Static functions behave very similar in C or C++, while nameless namespaces are obviously C++ only. nameless namespaces also add extra level in indentation and I don't like that :)

So, I'm happy to see that use of static for functions isn't deprecated anymore.