装饰器

Posted 2021-01-05 wrw202

1.高阶函数定义

a.函数接收的参数是一个函数名

def foo():
    time.sleep(2)
    print(‘hello‘)
def test(func):
    print(func)
    start_time=time.time()
    func()
    stop_time=time.time()
    print(‘running %s‘% (stop_time-start_time))
test(foo)

b.不改变函数的调用方式

def foo():
    print(‘from the foo‘)

def test(func):
    return func
foo=test(foo)
foo()
c.闭包

def father(name):
    # print(‘from father %s‘% name)
    def son():
        # name=‘kevin_1‘
        print(‘my father is %s‘% name)
        def grandson():
            print(‘my yeye is %s‘ % name)
        grandson()
    # print(locals())
    son()
father(‘kevin‘)

装饰器

def timmer(func):  #func=test
    def wrapper():
        start_time=time.time()
        func()  #test()
        stop_time=time.time()
        print(‘runing time %s‘ %(stop_time-start_time))
    return wrapper
def test():
    time.sleep(2)
    print(‘running‘)
test=timmer(test)  #test=wrapper
test()   #wrapper()
装饰器return test

def timmer(func):  #func=test
    def wrapper():
        start_time=time.time()
        res=func()  #test()
        stop_time=time.time()
        print(‘runing time %s‘ %(stop_time-start_time))
        return res
    return wrapper
@timmer #test=timmer(test)   test=wrapper
def test():
    time.sleep(2)
    print(‘running‘)
# test()   #wrapper()

res=test()  #test
print(res)

 函数加参数

def timmer(func):
    def wrapper(*args,**kwargs):
        start_time=time.time()
        res=func(*args,**kwargs)
        stop_time=time.time()
        return res
    return wrapper
@timmer
def func(*args,**kwargs):
    time.sleep(2)
    print(‘%s,%s‘%(args,kwargs))
    return 1234

func(‘kevin‘,19,age=19)