Re: boost::function syntax

From: shyamemani (shyamemani_at_[hidden])
Date: 2003-08-26 20:16:58

So combining this response with your response to Edward regarding 
standardization of boost.signal, shouldn't this be a big concern, 
since the use-case which I illustrated is quite commonly used in 
event based systems?

      But if this can be ironed out I think providing it as a 
language extension is better because then C++ can become a language 
which has built-in semantics for  use of the standard design 
patterns.  And then we programmar's and designers can live happily 
ever after .... 

Regards,
Shyam

--- In Boost-Users_at_[hidden], Douglas Gregor <gregod_at_c...> 
wrote:
> On Tuesday 26 August 2003 07:36 pm, shyamemani wrote:
> > I hate writing code in mailing list but here is a sample of what I
> > want to do.  I have a tree data strucutre class which fires event 
and
> > each event has some different parameters that are passed to it.  
What
> > I want to illustrate is that by calling one register function I 
get
> > access to three events.  In boost.signal this would require that 
the
> > client call the connect for each event.  Is this a good 
application
> > for this library?
> 
> Perhaps not. When you have multiple events going to a single 
listener from a 
> single source, signal/slot mechanisms aren't as useful as the 
> interface/listener paradigm you are already using. Signals might be 
> appropriate if you had a single event that could be any of those 
three:
> 
> 	enum NodeEvent { node_added, node_changed, node_deleted };
> 	boost::signal<void (NodeEvent event, Node* node)> onNodeEvent;
> 
> This may have some advantages over the iterface/listener approach 
you're using 
> (for instance, the automatic disconnect when trackable objects are 
destructed 
> or the ability to use Bind/Lambda), but it's very likely that 
Signals is not 
> the right choice for this interface.
> 
> 	Doug