title: URL Checker in Clojure?
body: <p>I have a URL checker that I use in Perl.  I was wondering how something like this would be done in Clojure.  I have a file with thousands of URLs and I'd like the output file to contain the URL (minus http://, https://) and a simple :1 for valid and :0 for false.  Ideally, I could check each site concurrently, considering that this is one of Clojure's strengths.</p>
  
  <h2>Input</h2>
  
  <p><a href="http://www.google.com" rel="nofollow noreferrer">http://www.google.com</a><br>
  <a href="http://www.cnn.com" rel="nofollow noreferrer">http://www.cnn.com</a><br>
  <a href="http://www.msnbc.com" rel="nofollow noreferrer">http://www.msnbc.com</a><br>
  <a href="http://www.abadurlisnotgood.com" rel="nofollow noreferrer">http://www.abadurlisnotgood.com</a><br></p>
  
  <h2>Output</h2>
  
  <p>www.google.com:1<br>
  www.cnn.com:1<br>
  www.msnbc.com:1<br>
  www.abadurlisnotgood.com:0<br></p>