Re: [Boost-users] [signals] thread-safe default combiner

From: Timmo Stange (ts_at_[hidden])
Date: 2007-02-09 15:21:30

Frank Mori Hess wrote:

> I'm noticing now that boost::last_value isn't thread-safe when used with a 
> non-void return value, since a thread can't in general be sure the signal 
> will have any slots connected to it when it is invoked.  Would it be 
> acceptable to make last_value throw an exception on the non-void, no slots 
> case?  Throwing an exception seems preferable to the dreaded "undefined 
> behaviour".  Or we could use a slightly modified default combiner with a 
> different name.

Returning an Optional if T is default constructible seems like
a viable refinement of that solution. I'm a little uncomfortable
with exceptions being thrown potentially everywhere along the
call chain as a default behaviour.

Regards

Timmo Stange