/**
* Add some HTML to be cached.
* This is done by providing a callback function that should
* return the HTML to be added. It will only be called if the
* item is not in the cache yet or when the cache has been invalidated.
*
* @since 1.20
*
* @param callable $computeFunction
* @param array $args
* @param string|null $key
*/
public function addCachedHTML($computeFunction, $args = array(), $key = null)
{
$this->getOutput()->addHTML($this->cacheHelper->getCachedValue($computeFunction, $args, $key));
}