Include php files only when needed at runtime
<p>I have some PHP code which looks roughly like this</p>

<pre><code>require_once 'cache.php';
require_once 'generator.php';

if (cache_dirty ('foo')) {
    cache_update ('foo', generate_foo ());
}

print cache_read ('foo');
</code></pre>

<p>My problem is that <code>generator.php</code> includes a whole mass of libraries and I don't want to load/parse it unless <code>cache_dirty</code> actually returns <code>false</code> at runtime.</p>

<p>I know there are PHP precompilers which can help but for now I need a quick fix. Is this possible?</p>
