title: Can't convert StringIO into String (TypeError) in Ruby
body: <p>When I use the code below, I get the following error message: 
  <code>can't convert StringIO into String (TypeError)</code></p>
  
  <pre><code>array_of_lines = []
  Zip::ZipInputStream::open(open("URL for zipped file", "rb")) do |io|
    file = io.get_next_entry
    puts "Downloading file #{file}"
    array_of_lines = io.readlines
    print "Downloaded ", array_of_lines.count, " elements.", "\n"
  end
  </code></pre>
  
  <p>Can someone help me? Thank in advance.</p>