But say you have sites of movies saved under a particular index
and sites of songs saved under a particular folder
In this case we have to extend so that user can search different things.
You could have your IndexFilters add a field to each of the
pages and categorize them. For instance, "type:song_lyrics" on
one type of file and "type:movies". You would also have to
add a query filter to handle "type:" queries. Then your search
form handler would just add the proper "type:xxx" text to the
search as appropriate.
