title: Recursively decrement a list by 1
body: <p>Very quick and easy homework question. I have it running ok but I think there's a better<br>
  way to do it. A more Pythonic way.<br>
  Here's my code to recursively decrement each element of a list by 1.  </p>
  
  <pre><code>l = range(30)  
  def recurseDecrMap(l, x = []):  
      if len(l) == 0:  
          return []  
      else:  
          x.append(l[0] -1)  
      recurseDecrMap(l[1:], x)  
      return x  
  </code></pre>
  
  <p>So thanks for any input. I'm trying to learn to do better recursion. Having trouble getting<br>
  the knack of it. </p>