title: Haskell http-client set User Agent String
body: <p>I'm writing a web crawler in Haskell with Scalpel.
  Basic code are:</p>
  
  <pre><code>Main :: IO ()
  Main = do
    request &lt;- parseRequest weblink
    p &lt;- httpLBS request &gt;&gt;= return . getResponseBody
  
    result &lt;- do
      r &lt;- return $ scrapeStringLike (L8.unpack p) torrentS
      return . fromJust $ r
  
    -- append
    mapM_ putStrLn $ result
  </code></pre>
  
  <p>The target website doesn't return the results. I suppose it checks the user agent string and respond differently to a real browser and a crawler.</p>
  
  <p>So how should I customize the User Agent String in <code>http-client</code>?
  or <code>wreq?</code></p>