Spawning new thread
I think it's wrong to say "async spawns a new thread" with std::launch::async. The specification doesn't mandate it:
"if policy & launch::async is non-zero — calls ... as if in a new thread of execution represented by a thread object with the calls to DECAY_COPY() being evaluated in the thread that called async."
Weasel words mean function may run on a thread pool.
--18.104.22.168 02:10, 29 May 2013 (PDT)
- Good point, someone even implemented launch::async as a pool, as far as I remember. --Cubbi 05:59, 29 May 2013 (PDT)
 It looks like std::async will be deprecated.
It looks like async is being deprecated according to this link. Maybe should mention it in the documentation.