John Nagle wrote:
I think we're back to using an abstract base class. The hacks to get around it introduce worse problems.
I would agree. I have been trying to find a way around the problem and have (sortof) by having a base class: template< typename CharT > class string_base { private: size_t len, cap; // length & capacity CharT * buf; // data buffer public: string_base( CharT * b, size_t c, size_t l ): len( l ), cap( c ), buf( b ){} // non-virtual implementation }; template< size_t n, typename CharT > class fixed_string: public string_base { private: CharT data[ n + 1 ]; public: fixed_string(): string_base( data, n + 1 ){} }; The problems with this revolve around swapping/construction/copying and interfacing with (in my case) basic_string_impl. I cannot find a way around these problems without sacrificing something.
Take a look at my approach at http://www.animats.com/source/index.html
That's a straightforward approach. The only fundamental objection is that you take a virtual function call overhead on some operations.
That's the same with both approaches. Both designs are fundamentally the same and I don't see a way around this. It would be interesting to do a comparison with the 3 approaches (raw strcpy, etc on a char[ n ] buffer; your approach and mine) in virtual and non-virtual situations to compare performance.
What needs to be done to that?
Are you aiming at supporting basic_string operations? If so, the class needs more work (all the find functions, for instance). If, however, you are just going for C-string replacement it is fine. One point on naming: the wide-character operations are wcscpy (strcpy), wcscat (strcat), wcscmp (strcmp), wcslen (strlen) and [v]swprintf (sprintf).
Should I check it into the Boost sandbox, and if so, how? Comments, please. Thanks.
Go for it! You need a sourceforge account with CVS write access to the boost-sandbox. There is documentation at the sourceforge site for setting it up and pointers to the various tools. You will need to contact an administrator for write access once you have the sourceforge stuff setup. Regards, Reece _________________________________________________________________ Express yourself with cool new emoticons http://www.msn.co.uk/specials/myemo