private IEnumerable <FormNodeSelector> SelectRemovableNodesByForm(IReadOnlyStatGraph statGraph) => from pair in statGraph.FormNodeCollections where _nodeRemovalDeterminer.CanBeRemoved(pair.Value) select pair.Key;
private bool CanStatGraphBeRemoved(IReadOnlyStatGraph statGraph) => statGraph.Nodes.IsEmpty() && statGraph.FormNodeCollections.IsEmpty() && _nodeRemovalDeterminer.CanBeRemoved(statGraph.Paths);
private IEnumerable <NodeSelector> SelectRemovableNodesByNodeType(IReadOnlyStatGraph statGraph) => from pair in statGraph.Nodes orderby pair.Key.NodeType where _nodeRemovalDeterminer.CanBeRemoved(pair.Value) select pair.Key;