how to check if function exists

Question

I want to implement my own std::make_unique function with the function being part of std namespace. I know this helper function is added to C++14 but I do not have it in C++11. So, I want to check it with some C++11 template magic (couldn't find any options with macros) to check if a function exists inside the std namespace and if it doesn't define it on my own. Is that possible? I don't even know where to start.

Answer 1

Your best bet is to use the standard __cplusplus macro which, for C++11, is 201103L. For C++14 onwards it will be a different value to this.

Answer 2

You cannot add a new function to the ::std namespace. You are only allowed to add specializations of existing templates, and even then only for your own types.