Hi, When I made a first glance of the proposal I expected that string_ref is some kind of type erasing non owning holder of a reference to an arbitrary string class. The imperfect silver bullet for the diversity of string types. Take a project that uses c++ libraries using std::string, Qt GUI and maybe a module that works with chunked strings (string composed out of a list of usually equally sized blocks of memory). At the boundaries of the software modules copies have to occur. Frequently the interface expects some kind of constant references to a certain string type. Most of the time the callee just wants to process the complete string or just a part of the string. So there might not even be the necessity to have random access hence no need for a contiguous copy of the string contents. Thats why I would prefer a facility that only requires that the source string is a forward range of characters in an arbitrary encoding. I do not think that it makes sense to only address contiguous sequences of characters. regards Andreas Pokorny