`sig
external new_icon_source : unit -> Gtk.icon_source
= "ml_gtk_icon_source_new"
external set_filename : Gtk.icon_source -> string -> unit
= "ml_gtk_icon_source_set_filename"
external set_pixbuf : Gtk.icon_source -> GdkPixbuf.pixbuf -> unit
= "ml_gtk_icon_source_set_pixbuf"
external set_direction_wildcarded : Gtk.icon_source -> bool -> unit
= "ml_gtk_icon_source_set_direction_wildcarded"
external set_state_wildcarded : Gtk.icon_source -> bool -> unit
= "ml_gtk_icon_source_set_state_wildcarded"
external set_size_wildcarded : Gtk.icon_source -> bool -> unit
= "ml_gtk_icon_source_set_size_wildcarded"
external set_direction : Gtk.icon_source -> Gtk.Tags.text_direction -> unit
= "ml_gtk_icon_source_set_direction"
external set_state : Gtk.icon_source -> Gtk.Tags.state_type -> unit
= "ml_gtk_icon_source_set_state"
external set_size : Gtk.icon_source -> Gtk.Tags.icon_size -> unit
= "ml_gtk_icon_source_set_size"
end`