title: Function to generate the unique combinations of a list in Haskell
body: <p>Is there a Haskell function that generates all the unique combinations of a given length from a list?</p>
  
  <pre><code>Source = [1,2,3]
  
  uniqueCombos 2 Source = [[1,2],[1,3],[2,3]]
  </code></pre>
  
  <p>I tried looking in Hoogle but could not find a function that did this specifically. Permutations does not give the desired result.</p>
  
  <p>Has anybody used a similar function before?</p>