return (color_t *)g_slist_find_custom(candidate_colors, other_color, gslist_color_compare);
GSListPtr tmp = g_slist_find_custom(candidate_colors, other_color, gslist_color_compare); if(tmp != NULL) { return (color_t *)tmp->data; } return NULL;
find_color(GSListPtr candidate_colors, color_t *other_color){	return (color_t *)g_slist_find_custom(candidate_colors, other_color,				   gslist_color_compare);}