----- Original Message ----- From: "Douglas Gregor" <gregod@cs.rpi.edu> To: <boost@lists.boost.org> Sent: Monday, March 08, 2004 6:42 AM Subject: Re: [boost] enumeration interface for boost::signals [...]
As for the capturing, you can use groups:
const int capture = -100000; // big negative number { boost::signals::scoped_connected captured = sig.connect(capture, slot_to_capture); // slot_to_capture always executes first, so it gets all the events. } // end of scope, slot_to_capture disappears
Good idea! However I don't want to require the slot itself to be aware whether it is capturing or not. I guess I can try something like this: struct server { typedef boost::signals::signal< void (event), until_true > signals; signals sig_; struct capture_wrapper { signals::slot_type s_; capture_wrapper( slot s ) : s_(s) {} bool operator()( event e ) { //how do I make the call? s_(e); //is it ok? return true; //stop propagation } } void capture( typename signals::slot_type s ) { capture_ = sig.connect( capture, capture_wrapper(s) ); } void remove_capture() { capture_.disconnect(); } boost::signals::scoped_connected capture_; };
If slots had a well-defined order, everything would be peachy.
Yep. As for the ordering, I think the SIGNALS_GROUP_TOP/SIGNALS_GROUP_BOTTOM flags should work just fine. We definitely need this feature. I also need an efficient way for accessing slots randomly. For instance some of the Win32 listbox messages have item indexes. I'd like to implement each item as a slot, but I need a way to access the slots based on the item index, so I could call just the right slot. listboxes can contain a lot of items so propagating the messages to all items is not an option. Eugene