16     GList *
result = g_list_copy(from);
    18     for (
const GList *item = items; item != NULL; item = item->next) {
    19         GList *match = g_list_find_custom(
result, item->data, cmp);
 
GList * pcmk__subtract_lists(GList *from, const GList *items, GCompareFunc cmp)
 
pcmk__action_result_t result