hpricot：An Hpricot Showcase：Hpricot CSS Search：Negating Searches

everyday Ruby 
>> require "hpricot"
=> true
>> doc = Hpricot('<html><body><p class="posted">A simple <b>test</b> string.</p><p>foo</p></body></html>')
=> #<Hpricot::Doc {elem <html> {elem <body> {elem <p class="posted"> "A simple " {elem <b> "test" </b>} " string." </p>} {elem <p> "foo" </p>} </body>} </html>}>
>> doc.search("p:not(.posted)")
=> #<Hpricot::Elements[{elem <p> "foo" </p>}]>
>> doc.search("p.posted")
=> #<Hpricot::Elements[{elem <p class="posted"> "A simple " {elem <b> "test" </b>} " string." </p>}]>