DEPRECATED Do not use.
This will revert back to the last set of matches (before the last
"destructive" set of operations). This undoes any change made to the set of
matched objects. Functions like find() and filter() change the
list of matched objects. The end() function will revert back to the last set of
matched items.
Note that functions that modify the document, but do not change the list of
matched objects, are not "destructive". Thus, calling append('something')->end()
will not undo the append() call.
Only one level of changes is stored. Reverting beyond that will result in
an empty set of matches. Example: