Part of bzrlib
| Function | topo_iter_keys | Undocumented |
| Function | topo_iter | Undocumented |
| Class | MultiParent | A multi-parent diff |
| Class | NewText | The contents of text that is introduced by this text |
| Class | ParentText | A reference to text present in a parent text |
| Class | BaseVersionedFile | Pseudo-VersionedFile skeleton for MultiParent |
| Class | MultiMemoryVersionedFile | Memory-backed pseudo-versionedfile |
| Class | MultiVersionedFile | Disk-backed pseudo-versionedfile |
| Function | gzip_string | Undocumented |
| Function | _topo_iter | Undocumented |
| Class | _Reconstructor | Build a text from the diffs, ancestry graph and cached lines |