public bool Ds\Deque::isEmpty( void )

<?php 
   deque = new \Ds\Deque([1, 2, 3, 4, 5]);   echo("The original deque: \n"); 

   print_r(deque); 
   var_dump($deque->isEmpty()); 
?>

<?php 
   deque = new \Ds\Deque([1, 2, 3, 4, 5]);   echo("The original deque: \n");   print_r(deque); 

   deque->clear();   var_dump(deque->isEmpty()); 
?>