title: Remove the last 2 characters from a string in Ruby?
body: <p>I'm collecting all my user's email addresses for a mass mailing like this:</p>
  
  <pre><code>def self.all_email_addresses
    output = ''
    User.all.each{|u| output += u.email + ", " }
        output
  end
  </code></pre>
  
  <p>However, I end up with an extra ", " on the string of email addresses.</p>
  
  <p>How can I get rid of this / is there a better way to get a comma separated list of email addresses?</p>