Re: Controlling the hardware volume

[Chris Vine <chris cvine freeserve co uk>]

On Wed, 25 Nov 2009 01:04:06 -0500
José Alburquerque <jaalburquerque cox net> wrote:
> On Tue, 2009-11-24 at 17:05 -0500, José Alburquerque wrote: 
> > The problem is that your trying to initialize a Glib::RefPtr<>&
> > from a Glib::RefPtr<> (which the std::list<> contains).  A
> > std::list<> is not designed to store references.
> 
> It doesn't seem clear what I was trying to say about lists not
> "storing" references.  I guess what I was trying to say is that I
> think trying to extract a reference by dereferencing a
> list<>::iterator is not doable. I was also trying to suggest another
> way get at the contents of the list.

You would expect std::list<T>::iterator::operator*() to return a
reference rather than a value type (it does on my version of libstdc++),
so it shouldn't fall foul of the preclusion of binding a temporary to a
non-const reference.

Isn't the explanation simply that Glib::RefPtr<Gst::MixerTrack> and
Glib::RefPtr<Gst::MixerTrack const> are different types (as they are)?

Glib::RefPtr<Gst::MixerTrack const> track = *iter (ie instantiating a
new RefPtr object rather than a reference) should work because it will
cause the templated version of the RefPtr's copy constructor to be
invoked, which will allow implicit conversion of the RefPtr's value
type.

Chris