Re: [Boost-users] [signals] signal-signal connections and thread-safety

From: Timmo Stange (ts_at_[hidden])
Date: 2007-02-11 17:02:42

Frank Mori Hess wrote:

>> No, I meant a partial specialization for optional<T> directly, i.e.
>> last_value<optional<T> >. That makes the return value of that function
>> object (in our case the combiner) "optional", which reflects the
>> intention to have it not throwing for an empty input range pretty
>> well, I think.
> 
> The work-around for compilers lacking partial specialization is to give the 
> specialization a different class name, right (e.g. last_optional<T>)?  So 
> providing a partial specialization would result in last_value<optional<T> 
> > throwing when compiled on some compilers and not on others.  It seems 
> less confusing to provide last_optional<T> only.

You can use last_value<optional<T> > on compilers that don't have
partial template specialization as well, the implementation is just
not as straightforward, but that won't be visible to the user.

Regards

Timmo Stange