title: Array.find method problem
body: <p>I find this line in the ZenTest source code:</p>
  
  <pre><code>result = @test_mappings.find { |file_re, ignored| filename =~ file_re }
  </code></pre>
  
  <p>The <code>@test_mappings</code> and <code>result</code> here are both Array object, but I didn't found 'find' method on Array class in ruby doc. I also tried it on irb:</p>
  
  <pre><code>irb(main):014:0&gt; Array.respond_to? :find
  =&gt; false
  irb(main):015:0&gt; [1,2,3].find
  LocalJumpError: no block given
          from (irb):15:in `find'
          from (irb):15:in `each'
          from (irb):15:in `find'
          from (irb):15
  irb(main):016:0&gt; [1,2,3].find{|x| x&gt;1}
  =&gt; 2
  </code></pre>
  
  <p>Could any one explain it to me? How could find method also return an Array object? thanks in advance.</p>