On Tue, Nov 27, 2012 at 10:44 AM, Yanchenko Maxim <maximyanchenko@yandex.ru> wrote:
27.11.12, 14:24, "Andrey Semashev" <andrey.semashev@gmail.com>":
+1, string_ref by definition doesn't own the referred characters. Its presence is enough indication that the storage of the characters has to be managed elsewhere.
Unfortunately there is absolutely no indication of its presence if you make the construction implicit. Implicitly constructible types are invisible at the point of use, this is the problem. This is exactly what I'm talking about: there should be clear indication of what's going on, and it should be at the point of use, not in function declaration or in docs. Making it implicit is a way to error-prone user code.
And from the user's perspective it should be as transparent as possible.
What about making implicit conversion from auto_ptr<T*> to T*? Enforcing use of get() is not transparent as possible either. What about getting rid of c_str()? Isn't safety the reason of having both?
When passing arguments to functions, c_str() and get() are exactly the things we want to get rid of. That's where string_ref helps. If you want to store string_ref in a container then either bear in mind that the string_refs do not own the storage or choose a different type for that purpose.