TRACE("s1", "sl_lookup: searching for key %p in skiplist %p", key, sl);
node_t *item = find_preds(NULL, NULL, 0, sl, key, FALSE);
// If we found an <item> matching the <key> return its value.
if (item != NULL) {
TRACE("s1", "sl_lookup: searching for key %p in skiplist %p", key, sl);
node_t *item = find_preds(NULL, NULL, 0, sl, key, FALSE);
// If we found an <item> matching the <key> return its value.
if (item != NULL) {