title: How do you unwire an action in Nitrogen?
body: <p>In <a href="http://nitrogenproject.com/" rel="nofollow noreferrer">Nitrogen, the Erlang web framework</a>, you wire actions like this:</p>
  
  <pre><code>wf:wire(send_message, #event { type=click, postback=send_message })
  </code></pre>
  
  <p>but if after that you run</p>
  
  <pre><code>wf:wire(send_message, #event { type=click, postback=send_message2 }),
  </code></pre>
  
  <p>then you get the action wired twice.</p>
  
  <p>How do you unwire the previous action or all actions of an element?</p>