An example of inheritance:

    class ExtendableStack is Stack
    {
	public:
	   function push (new_item: ItemType)
		// override "push" 
	   {	if (stack_top_index >= stack_size)
		{  
		   stack_size *= 2;
		   renew (buffer, stack_size);
		} 
		Stack::push(new_item);
	   };
    };

More examples:

• a function
• a class
• object instantiation
• a parameterized class
• using parameterized classes