Through the template, you can imagine an object to be tasted by multiple roles.
These characters each completed their own tasks, but they are abstract; can pass through parameters
These roles themselves are also templates
Template
Class CreationPolicy = CREATEUSINGNEW,
What is this line?
Description CREATEPOLICY is a template that requires a class parameter;
Why don't we transfer it outside and then transfer it, the purpose of doing this is to be simple
We can treat templates as combined technology, which separates algorithms and objects
