[Base] Python higher order function nested function + + == closure decorator

+ + Higher order functions nested function closure == decorator

• What is a decorator
• Principle II decorator to follow
• Three realize decorator knowledge base
• Four higher-order functions
• Five nested functions
• Six closures
• Seven no-argument decorator
• Eight decorator application examples
• Nine times out decorator

reference:

https://www.cnblogs.com/linhaifeng/articles/6140395.html

https://www.cnblogs.com/haiyan123/p/8387769.html