hpricot：An Hpricot Showcase：Hpricot Challenge：Does an Element Meet a Selector?

まんま

>> require "hpricot"
=> true
>> doc = Hpricot.parse(%{<div class='outer'><div class='inner'>text</div></div>})
=> #<Hpricot::Doc {elem <div class="outer"> {elem <div class="inner"> "text" </div>} </div>}>
>> doc.at('.outer')
=> {elem <div class="outer"> {elem <div class="inner"> "text" </div>} </div>}
>> doc.at('.outer').search('.inner')
=> #<Hpricot::Elements[{elem <div class="inner"> "text" </div>}]>
>> doc.at('.outer').search('.inner').empty?
=> false
>> doc.at('.inner')
=> {elem <div class="inner"> "text" </div>}
>> doc.at('.inner').at('.outer')
=> nil
>> doc.at('.inner').search('.outer')
=> #<Hpricot::Elements[]>
>> doc.at('.inner').search('.outer').empty?
=> true