python 装饰器 递归函数 记录

• 第一步：简单实现装饰器

def login(func):    print("in Login")    return funcdef tv(name):    print("{name} in TV".format(name = name))tv = login(tv)tv('Jack')# out:# in Login# Jack in TV

• 第二步：同上
  效果相同，但是使用的是@login

def login(func):    print("in Login")    return func@logindef tv(name):    print("{name} in TV".format(name = name))#tv = login(tv)tv('Jack')# out:# in Login# Jack in TV

但是出现问题，注销最后的执行语句仍有输出，原因在于@login的调用，即@login相当于执行了tv = login(tv) 所以才有输出。

def login(func):    print("in Login")    return func@logindef tv(name):    print("{name} in TV".format(name = name))#tv = login(tv)#tv('Jack')# out:# in Login

如下调整可解决

def login(func):    def inner(arg):        print("in Login")        # return func        func(arg)    return inner@logindef tv(name):    print("{name} in TV".format(name = name))#tv = login(tv)tv('Jack')# out:# in Login# Jack in TV

简单的递归函数

#!/usr/bin/env python#递归函数def calc(num):    print("Number:",num)    if num/2 > 1:        calc(num/2)        print("After Number:",num/2)calc(10)# Number: 10# Number: 5.0# Number: 2.5# Number: 1.25# After Number: 1.25# After Number: 2.5# After Number: 5.0

递归实现斐波那契数列

#   Fibonacci sequence#   F[n]=F[n-1]+F[n-2](n>=2,F[0]=1,F[1]=1)#   斐波那契数列：1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, ...fibList = [1,1]def getFib(fibList):    print(fibList)    if fibList[-1] + fibList[-2] < 300:        fibList.append(fibList[-1] + fibList[-2])        getFib(fibList)        pass    passgetFib(fibList)print("[FINAL]:",fibList)# [1, 1]# [1, 1, 2]# [1, 1, 2, 3]# [1, 1, 2, 3, 5]# [1, 1, 2, 3, 5, 8]# [1, 1, 2, 3, 5, 8, 13]# [1, 1, 2, 3, 5, 8, 13, 21]# [1, 1, 2, 3, 5, 8, 13, 21, 34]# [1, 1, 2, 3, 5, 8, 13, 21, 34, 55]# [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]# [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144]# [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233]# [FINAL]: [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233]