On Sun, Mar 15, 2009 at 14:34, Thorsten Ottosen <thorsten.ottosen@dezide.com> wrote:
Scott McMurray skrev:
I agree that self-assignment is uncommon enough for an explicit check to be a pessimization, though. Is the algorithm you have ( the attachment to the first post in this thread doesn't have operator= ) really more efficient than one that doesn't need the explicit check?
Here's the current version. I guess I would have to do some test to make 100% sure it's faster.
I would be interested to see if the manual inlining (essentially) really does make a noticeable speedup. For small n it wouldn't surprise me if it did, though. The important part, though, is that what you have should work just fine for self-assignment. diff will be 0, so you go into the first if, pop_back nothing, and then copy over it with itself. So I think you actually wrote a self-assignment-safe version without realizing it. ~ Scott P.S. What kind of exception-throwing limitations are you assuming? That (*this).~auto_buffer(); is scary, especially when you don't yet have the replacement memory initialized...