Classes can be marked for operations similar to the standard Emacs commands M-x tags-search and M-x tags-query-replace (see also see Tags-like Functions.)
Toggle the mark of the line point is in or for as many lines as given by a prefix command. This command can also be found in the class’ context menu.
Unmark all classes. With prefix argument C-u, mark all classes in the tree. Since this command operates on the whole buffer, it can also be found in the buffer’s object menu.
Marked classes are displayed with an
> in column one of the tree
display, like in the following example
|> Collection | IndexedCollection... |> Set | Dictionary