Andy Tai schreef op di 14-06-2022 om 11:52 [-0700]:
> question: how to create object representing Gtk+ (version 3)
> interfaces? For example.
> 
> (let (model (make <GtkTreeModel>)))
> 
> would fail  because GtkTreeModel is an interface, not class derived
> from GObject.

By definition, you cannot instatiate interfaces, but you can
instantiate classes derived from GtkTreeModel?  Seems like you answered
the question yourself?
Maybe guile-gi even supports defining an implementation yourself in
Scheme with GOOPS ...

Greetings,
Maxime.