Re: [Boost-users] Deferred Function calls

From: Nat Goodspeed (ngoodspeed_at_[hidden])
Date: 2006-10-25 08:20:37

> -----Original Message-----
> From: boost-users-bounces_at_[hidden] [mailto:boost-users-
> bounces_at_[hidden]] On Behalf Of Matt Davies
> Sent: Tuesday, October 24, 2006 4:33 PM
> To: boost-users_at_[hidden]
> Subject: [Boost-users] Deferred Function calls
> 
> I am implementing a signal & slots implementation with a twist.
Normally
> when a signal is fired the connected slots are called immediately.  I
will
> need to defer the actual calls to be invoked later.  Basically I need
to
> store the function reference (via pointer or functor) and the
accompanying
> parameter values to a 'composite' object.  This composite object will
be
> stored on a buffer.  Later another processor will pick this object of
the
> buffer and then invoke the actual function call.

[Nat] Let me try to paraphrase the question to see if I understand.

You aren't directly using Boost.Signals because when you call a signal
it immediately passes control to each of its slots.

Your slots have non-empty parameter signatures. The code that triggers
the deferred call has matching argument values. If an immediate call
were acceptable, you'd simply use a boost::signal and call it with those
argument values.

So... as Delfin Rojas suggested, you could use boost::bind to bind your
boost::signal object with the argument values you later want passed to
each connected slot. (I haven't tried this myself.) In the absence of
bind placeholders (e.g. _1), bind will produce a nullary functor that
you can store in a boost::function<void (void)>. When you later call
that functor with no arguments, it should call each connected slot with
the bound arguments.

If this doesn't answer your question, please explain what we're missing.