title: How do I pass an argument to array.map short cut?
body: <p>Given the following array <code>a</code>:  </p>
  
  <pre><code>a = [1, 2, 3, 4, 5]  
  </code></pre>
  
  <p>How do I do:</p>
  
  <pre><code>a.map { |num| num + 1 }  
  </code></pre>
  
  <p>using the short notation:</p>
  
  <pre><code>a.map(&amp;:+ 1)  
  </code></pre>
  
  <p>or:</p>
  
  <pre><code>a.map(&amp;:+ 2)  
  </code></pre>
  
  <p>where 1 and 2 are the arguments?</p>