hpricot：An Hpricot Showcase：Hpricot Challenge：Checking for a Few Attributes

everyday Ruby 
>> require "hpricot"
=> true
>> doc = Hpricot('<a href="http://www.foo1.org/">foo1</a><a href="http://www.foo1.org/">foo2</a><form action="hoge1"></form><form action="hoge2"></form>')
=> #<Hpricot::Doc {elem <a href="http://www.foo1.org/"> "foo1" </a>} {elem <a href="http://www.foo1.org/"> "foo2" </a>} {emptyelem <form action="hoge1">} {emptyelem <form action="hoge2">}>
>> doc.search("[@href]")
=> #<Hpricot::Elements[{elem <a href="http://www.foo1.org/"> "foo1" </a>}, {elem <a href="http://www.foo1.org/"> "foo2" </a>}]>
>> doc.search("[@action]")
=> #<Hpricot::Elements[{emptyelem <form action="hoge1">}, {emptyelem <form action="hoge2">}]>
>> doc.search("[@href]|[@action]")
=> #<Hpricot::Elements[{elem <a href="http://www.foo1.org/"> "foo1" </a>}, {elem <a href="http://www.foo1.org/"> "foo2" </a>}]>
>> doc.search("[href]|[action]")
=> #<Hpricot::Elements[]>
>> doc.search("[@href][@action]")
=> #<Hpricot::Elements[{elem <a href="http://www.foo1.org/"> "foo1" </a>}, {elem <a href="http://www.foo1.org/"> "foo2" </a>}]>

うまく動いている？？？