Using Python to Implement the Decorator Pattern

Decorator pattern is a structural design pattern that allows dynamic addition of functionality to existing objects without changing object code or using subclasses. In Python, you can use closures and decorator syntax to implement decorator patterns. The following is a complete sample code for implementing the decorator pattern using Python: python #Define a decorator function def wrap_function(func): def wrapper(): print("Before calling original function") func() print("After calling original function") return wrapper #Define a primitive function def original_function(): print("Inside original function") #Decorate the original function with a decorator decorated_function = wrap_function(original_function) #Calling wrapped functions decorated_function() In the above code, wrap_ Function is a decorator function that takes a function as input and returns an internal function wrapper. The internal function wrapper is used to wrap the original function and add additional functionality before and after calling the original function. Declaration of origin_ After using function as the original function, call wrap_ Function (original_function) applies the decorator to the original function and assigns the returned function to decorated_ Function. Finally, by calling decorated_ Function() to call the decorated function. During this process, the decorator function wrap_ The additional functions in the function will be executed before and after the original function call. Run the above code, and the output will be: Before calling original function Inside original function After calling original function This example demonstrates the basic process of implementing decorator patterns using Python. You can write more complex decorators according to specific needs to achieve more functional additions.