title: Cucumber table + find("table tr:eq(x)") not working right
body: <p>I have this cucumber task:</p>
  
  <pre><code>Then I should see following posting modes
          | row | day  | hour | minute | location | category |
          | 1   | 1    | 7    | 0      | 29       | 6        |
          | 2   | 2    | 8    | 5      | 27       | 7        |
          | 3   | 3    | 9    | 10     | 28       | 18       |
          | 4   | 4    | 15   | 15     | 29       | 18       |
          | 5   | 5    | 17   | 20     | 27       | 7        |
          | 6   | 6    | 20   | 30     | 28       | 6        |
          | 6   | 0    | 22   | 50     | 29       | 7        |
  </code></pre>
  
  <p>And behind it there is this description:</p>
  
  <pre><code>Then /^I should see following posting modes$/ do |table|
    table.hashes.each do |posting|
        within("#itemPosting .attributeContainer table tbody tr:eq(#{posting[:row]})") do
              find("#item_posting_day").value.should == posting[:day]
              find("#item_posting_hour").value.should == posting[:hour]
              find("#item_posting_minute").value.should == posting[:minute]
              find("#item_posting_location").value.should == posting[:location]
              find("#item_posting_category").value.should == posting[:category]
        end
    end  
  end
  </code></pre>
  
  <p>So this part:</p>
  
  <pre><code>tr:eq(#{posting[:row]})
  </code></pre>
  
  <p>doesn't work(it goes to next step, and then gives an error that #item_posting_day is not found.)</p>
  
  <p>But if I do this instead:</p>
  
  <pre><code>tr:eq(4)
  </code></pre>
  
  <p>It works (finds the #item_posting_day field, gets its value, and then gives an error saying that value is not what is expected to be, but that's ok).</p>
  
  <p>So I don't understand what's the problem with using this syntax:</p>
  
  <pre><code>tr:eq(#{posting[:row]})
  </code></pre>