id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
10610,Add unwrap shared_future constructor,viboes,viboes,"Following N4123, add unwrap shared_future constructor

See also https://github.com/cplusplus/concurrency_ts/issues/58

{{{


shared_future(future<shared_future<R>>&& rhs) noexcept;

Effects:
    Constructs a shared_future object from the shared state referred to by rhs. The shared_future becomes ready when one of the following occurs:

        Both the outer future and the inner shared_future are ready. The shared_future inherits the value or the exception from the inner shared_future.
        The outer future is ready but the inner shared_future is invalid. The shared_future gets an exception of type std::future_error, with an error code of std::future_errc::broken_promise.

Postconditions:

        valid() returns the same value as rhs.valid() prior to the constructor invocation.
        valid() == true.
        rhs.valid() == false.


}}}
",Feature Requests,assigned,To Be Determined,thread,Boost 1.57.0,Problem,,,