How to share global constants with minimum overhead at runtime?

Question

I am using C++11. I am not allowed to use external libraries like boost etc. I must use STL only.

I have a number of events, which must be identified as string const

Answer 1

Global const std::string has one drawback it need processing during startup and creates copy of string literal.

The linked SO answear uses constexpr std::string_view and this is cool solution since constructor is constexpr so nothing have to be done on startup. Also it doesn't create any copy. Problem is that this is C++17

Use of const char [] (or auto or constexpr) is old proven solution. You can compare std::string with it without any extra overhead.

You can create header file for all that strings and let linker to remove all duplicates. It was working like that in old C++.