How to specify a const reference to a const pointer?

Question

Probably a conceptual mistake from my part but let's say I have a function which takes a char * as a parameter; that is, a C-style string. But I want to make sure that char * is pointing to something. So could I use something like:

foo(const char * const &cstring)

to specify that I'm expecting cstring to be a const reference to a const char *? This way I wouldnt need to check for NULL pointers inside foo.

Answer 1

What you've written assures that the reference itself is bound to a valid pointer that may still be null. There isn't any compile time way to do what you want.

Your best option to to not use C-strings but take a std::string by value or const reference. If that isn't suitable then take the const char*, put in the function documentation that null is not accepted, and do a runtime assert that the pointer isn't null.