Rails - May 2005 - tag, content_tag: are nil-valued options ever useful?

In a number of places in my code I pass options whose value are
'''' or
nil to one of the tag-generation helper methods. In the HTML this shows 
up as, e.g.

    <span class="">

Now, this can be pretty wasteful, but I don''t want to change my evil 
ways. Thus I''d rather have the framework throw out these options than 
do it myself. AFAICT, all tag generation is funnelled through 
ActionView::Helpers::TagHelper#tag_options where nil-valued options 
could easily be filtered.

There are two question I''m not clear about, though:
* Is there ever a use for an empty attribute?
* Can it be useful to differentiate between nil and empty as the value 
of an option?

Michael

-- 
Michael Schuerig                          Thinking is trying to make up
mailto:michael-q5aiKMLteq4b1SvskN2V4Q@public.gmane.org                for a gap
in one''s education.
http://www.schuerig.de/michael/                          --Gilbert Ryle