Re: [Boost-users] [signals] Automatic connection management and MT

From: Timmo Stange (ts_at_[hidden])
Date: 2007-02-07 14:57:14

Doug Gregor wrote:

> Not necessarily. One could have a "signal_impl_with_combiner"  
> template that derives from "signal_impl", and stores the combiner.  
> Most of the shared code will still be in signal_impl, of course.

Right, I'm going to use that, but:
While I was running the first experiments with a version of
Signals from which I stripped grouping/naming, I've now had
a closer look at named_slot_map. I know that it has been con-
sidered a not so lucky design and one can tell from the code
that it gave you some headaches. I frankly find the performance
aspects unacceptable for my personal use (shared_ptr<void>
to a heap allocated group name, boost::function as a comparison
operator), so the only option for me seems to be turning the
named_slot_map into a template, with the obvious propagation
effects for the rest of Signals. I would also add a
signals::no_name type to be able to get an instantiation which
would use a list or deque for the slots.

I know that this will result in the infamous template bloat on
some compilers, with code duplication for each Group/GroupCompare
pair, potentially in several compilation units. On the other hand
I won't be able to find the necessary motivation to work on some-
thing I'm never going to use myself.

So, if such a design change is a show-stopper, I'd rather be told
now than later ;).

Thanks for the insight on the call_notification mechanism.

Regards

Timmo Stange