Re: sigc++ signals and GSignal

["Murray Cumming" <murrayc murrayc com>]

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> Hi folks,
>
> This is mainly a sigc++ question, but relates to GSignal, so I hope
> it's on topic.
>
> With GSignal, you can connect a handler, or override a virtual
> function in the object class.  In addition, you can specify whether
> the virtual function is run first or last, and then connect signals
> to run before /or/ after the signal if it runs last.
>
> With sigc::signal, I can only run signals in the order they were
> connected.  I'd like to mimic GSignal, in that I want to provide a
> default implementation which may be overridden, but if overridden, I
> might not want the default to run at all.  Is this possible?

Not easily. You could connect ane empty virtual member method as a default
handler to your member signal. But making sure that it would be run before
or after other handlers would be difficult. Maybe you could play with the
signal's slot_list<> to change the calling sequence.


Murray Cumming
murrayc murrayc com
www.murrayc.com
www.openismus.com