Howard Hinnant <hinnant@twcny.rr.com> writes:
On Jul 8, 2004, at 11:10 AM, David Abrahams wrote:
Are there really any repercussions from making a noncopyable type into a moveable type, other than that you might want to find ways to take advantage of the new moveability?
If I had an rvalue reference available today, I would design the interface of the read and write locks differently. For example, instead of:
void f(rw_mutex& m) { rw_mutex::upgradable_read_lock r(m); if (...) { rw_mutex::write_lock w(r); //... w.transfer_to(r); } //Point A }
I would propose:
void f(rw_mutex& m) { rw_mutex::upgradable_read_lock r(m); if (...) { rw_mutex::write_lock w(move(r)); //... r = move(w); } //Point A }
The original code would not compile: write_lock would not accept an lvalue upgradable_read_lock and transfer_to would not exist.
I believe you can have the latter syntax with or without moveability. -- Dave Abrahams Boost Consulting http://www.boost-consulting.com