public _FetchHandler(Graph graph, object fetches, Dictionary <object, object> feeds = null, Action feed_handles = null) { _fetch_mapper = _FetchMapper.for_fetch(fetches); foreach (var fetch in _fetch_mapper.unique_fetches()) { switch (fetch) { case Operation val: _assert_fetchable(graph, val); _targets.Add(val); _ops.Add(true); break; case Tensor val: _assert_fetchable(graph, val.op); _fetches.Add(val); _ops.Add(false); break; default: throw new NotImplementedException("_FetchHandler fetch"); } } _final_fetches = _fetches; }