python 装饰器

#函数返回值+1
def make(func):
    def wrapper(*args,**kwds):
        return func(*args,**kwds) + 1
    return wrapper

@make
def add():
    return 4

print add()  #输出5

#函数返回值+N
def makearg(num):
    def make(func):
        def wrapper(*args,**kwds):
            return func(*args,**kwds) + num
        return wrapper
    return make

@makearg(num=1)
def add(n):
    return n + 4
    
print add(4) # 输出9

装饰器传参 参考 https://www.cnblogs.com/serpent/p/9445592.html

#检测函数执行时间
import time
import sys
def timer(func):
    def wrapper(*args,**kwds):
        start=time.time()
        func(*args,**kwds)
        end=time.time()
        print "exe function %s take %s time" %(func.__name__,str(end - start))
    return wrapper

@timer
def add():
    print "start"
    time.sleep(5)
    print "ending"

add()