title: Non empty Iterator turned empty after printing
body: <p>In scala, I read a file using getLines which returned a non-empty Iterator. Then I printed the lines using for loop. After that when I tried to print again it says empty Iterator. Can someone explain?</p>
  
  <pre><code>scala&gt; c
  res1: Iterator[String] = non-empty iterator
  
  scala&gt; println(c)
  non-empty iterator
  
  scala&gt; for ( line &lt;- c) println(line)
  
  insert into songlist (id, artist, title, numone) values (1, 'ABBA', 'WATERLOO', 0);
  insert into songlist (id, artist, title, numone) values (2, 'ABBA',.............
  
  scala&gt; var d = for ( line &lt;- c) println(line)
  d: Unit = ()
  scala&gt; c
  res8: Iterator[String] = empty iterator
  </code></pre>