title: Determine whether a string contains any of a set of strings
body: <p>I'm using <code>Mechanize</code> to interact with a few web pages, and I'm trying to determine whether a given form submission resulted in an error.</p>
  
  <p>Right now I'm doing this:</p>
  
  <pre><code>agent.page.body.include?("I'm an error message!")
  </code></pre>
  
  <p>But I just discovered <em>another</em> error message. Since I don't want to do:</p>
  
  <pre><code>agent.page.body.include?("I'm an error message!") || agent.page.body.include?("Another error message")
  </code></pre>
  
  <p>How can I determine whether the page body contains <em>either</em> error message?</p>