It is deprecated in favor of the regular GLib functions. https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/718
This is *much* nicer than repetitive "imports.gi" lines ... https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/399
https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/350
Arrow notation is great, use it consistently through-out the code base to bind `this` to anonymous functions, replacing the more overbose Lang.bind(this, function() {}). https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/23