title: in_array for a combo value ('test','value')
body: <p>I'm trying to use in_array or something like it for associative or more complex arrays. </p>
  
  <p>This is the normal in_array </p>
  
  <pre><code>in_array('test', array('test', 'exists')); //true
  in_array('test', array('not', 'exists')); // false
  </code></pre>
  
  <p>What I'm trying to search is a <strong>pair</strong>, like the combination 'test' and 'value'. I can set up the combo to be searched to <code>array('test','value')</code> or <code>'test'=&gt;'value'</code> as needed. But how can I do this search if the array to be searched is </p>
  
  <pre><code>array('test'=&gt;'value', 'exists'=&gt;'here');
  or
  array( array('test','value'), array('exists'=&gt;'here') );
  </code></pre>