hpricot：An Hpricot Showcase：Hpricot CSS Search：Selecting by Hierarchy

everyday Ruby 
>> require "hpricot"
=> true
>> doc = Hpricot('<div class="entryPermalink"><a href="http://www.foo1.org/">foo1</a><a href="http://www.foo2.org/">foo2</a></div><div id="menu"><a href="http://www.foo3.org/">foo3</a></div><div class="entryPermalink"><a href="http://www.foo4.org/">foo4</a></div>')
=> #<Hpricot::Doc {elem <div class="entryPermalink"> {elem <a href="http://www.foo1.org/"> "foo1" </a>} {elem <a href="http://www.foo2.org/"> "foo2" </a>} </div>} {elem <div id="menu"> {elem <a href="http://www.foo3.org/"> "foo3" </a>} </div>} {elem <div class="entryPermalink"> {elem <a href="http://www.foo4.org/"> "foo4" </a>} </div>}>
>> (doc/"div.entryPermalink a").empty
=> #<Hpricot::Elements[{emptyelem <a href="http://www.foo1.org/">}, {emptyelem <a href="http://www.foo2.org/">}, {emptyelem <a href="http://www.foo4.org/">}]>
>> (doc/"div.entryPermalink"/"a").empty
=> #<Hpricot::Elements[{emptyelem <a href="http://www.foo1.org/">}, {emptyelem <a href="http://www.foo2.org/">}, {emptyelem <a href="http://www.foo4.org/">}]>