title: How to fix "parse error on input" in haskell?
body: <pre><code>Prelude Data.Set&gt; :load hello
  [1 of 1] Compiling Main             ( hello.hs, interpreted )
  
  hello.hs:11:11: parse error on input `&lt;-'
  Failed, modules loaded: none.
  Prelude Data.Set&gt; h &lt;- IO.openFile "testtext" IO.ReadMode
  Prelude Data.Set&gt; 
  </code></pre>
  
  <p>The same line [h &lt;- IO.openFile "testtext" IO.ReadMode] inside hello.hs throws the error. How do i fix this? What am I doing wrong?</p>
  
  <p>[EDIT]
  Source and output: <a href="http://pastebin.com/KvEvggQK" rel="noreferrer">http://pastebin.com/KvEvggQK</a></p>