title: How to dispatch a multimethod on the type of an array
body: <p>I'm working on a multimethod that needs to update a hash for a bunch of different things in a sequence. Looked fairly straitforward until I tried to enter the 'type of an array of X'.</p>
  
  <pre><code>(defmulti update-hash #(class %2))
  
  (type (byte 1))
  =&gt; java.lang.Byte
  (defmethod update-hash java.lang.Byte [md byte]
    (. md update byte))
  
  (type (into-array  [ (byte 1)]))
  =&gt; [Ljava.lang.Byte;
  (defmethod update-hash &lt; WHAT GOES HERE &gt; [md byte]
  </code></pre>