vs->missing_val_dialog = missing_val_dialog_create (GTK_WINDOW (toplevel));
vs->var_type_dialog = var_type_dialog_create (GTK_WINDOW (toplevel));
vs->missing_val_dialog = missing_val_dialog_create (GTK_WINDOW (toplevel));
vs->var_type_dialog = var_type_dialog_create (GTK_WINDOW (toplevel));