Re: Clarification for the application of GVariant/Glib::Variant maybe types

[José Alburquerque <jaalburquerque gmail com>]

On Fri, 2011-10-07 at 12:54 +0200, Murray Cumming wrote:
> On Fri, 2011-10-07 at 09:29 +0200, Markus Elfring wrote:
> > By which (member) function can such a variable be marked to contain an
> > unknown
> > value?
> > (Do I overlook a programming interface once more?)
> > http://developer.gnome.org/glibmm/2.30/classGlib_1_1VariantBase.html
> 
> It looks like we don't have any API yet to create a "maybe"
> Glib::Variant. The C API is g_variant_new_maybe() but we don't seem to
> use that yet. I don't know how we would support this in a template
> specialization.

One possible way might be to add a create_maybe() method to
Glib::VariantContainerBase that could use the
Glib::VariantBase::get_type() method of its children to create the maybe
type, but I'm not sure it would work.  I guess I can try and add it for
glibmm-2.32 and see if it works.

> 
> Note that GVariant generally doesn't have set functions. It's meant to
> be an invariant type. That probably makes it unsuitable for general use
> anyway.
> 

-- 
José