title: Passing filter as an angular directive param
body: <p>I would like to pass w filter as a param to a custom directive in my app. I would like to do something like:</p>
  
  <p>Usage in application:</p>
  
  <pre><code>&lt;my-directive data='dataVariable' dataFilter='numericFilter: 123'/&gt;
  </code></pre>
  
  <p>Directive template:</p>
  
  <pre><code>&lt;span&gt; {{ data | dataFilter }} &lt;/span&gt;
  </code></pre>
  
  <p>Directive:</p>
  
  <pre><code>...
  scope: {
    data: '=',
    dataFilter: '@'
  }
  ...
  </code></pre>
  
  <p>When I do it as shwon above I get error related to syntax (<code>:</code> is not recognized), dependency injection (filter is not found) or the filter simply does nothing.</p>