{
public function quack()
{
echo "I don't even quack";
}
}
class Duck
{
public $fly_behavior;
public $quack_behavior;
public function swim()
{
echo "swimming duck";
}
public function display()
{
echo "be a duck";
}
public function performQuack()
{
$this->quack_behavior->quack();
}
public function performFly()
{
$this->fly_behavior->fly();
}
}
$duck = new Duck();
$duck->quack_behavior = new MakeNoise();
$duck->performQuack();
