26.10.2015, 18:49, "John Weeks" <j...@wavemetrics.com>: >> Both are correct, since one is implemented in terms of the other. That means >> they MUST expand to exactly the same assembly (and they do, I've just >> tested). >> >> If you're seeing something different, the problem is probably your code. And >> that's why Marc is recommending qSwap: because people don't know how to use >> std::swap. There's a big gotcha: you MUST NOT write the "std::" part of >> std::swap. > > At the risk of making a fool of myself, what is the difference? I thought I > had learned that namespaces were just a scoping mechanism for names to avoid > name collisions. Why does this make such a difference in the generated code? > > I'm old enough now that the risk of making a fool of myself is a small price > to pay in order to learn something.
Unqualified swap() invokes argument-dependent lookup which may bring in custom overload of swap declared outside of std namespace. -- Regards, Konstantin _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
