title: Check if array sub-keys have empty values
body: <p>I have an array that looks like this:</p>
  
  <pre><code>$arr = array(
  
    'abc' =&gt; array(
               'subkey1' =&gt; '',
               'subkey2' =&gt; false,             
               'subkey3' =&gt; 0,  
               ...                          
             ),
  
    'def' =&gt; array(
               'subkey1' =&gt; '',
               'subkey2' =&gt; 555,             
               'subkey3' =&gt; 0,  
               ...                          
             ),
  
    ...
  
  );
  </code></pre>
  
  <p>I want to unset all parent elements in which ALL subkeys have empty values, like <code>0</code>, <code>''</code>, <code>false</code>, <code>null</code>. In my example <code>abc</code> needs to be unset.</p>
  
  <p>Currently I'm manually checking within a foreach loop if each subkey is empty, but the if condition is huge because I have 8 subkeys :)</p>
  
  <p>Is there a nicer alternative for this?</p>