python 修改的函数装饰器

把好的代码记录下来 方便以后学习

修改的函数参数装饰器

from functools import wraps

import time

import logging

def warn(timeout):

    #timeout=[timeout]  python 2.x

    def decorator(func):

        def wrapper(*args,**kargs):

            start = time.time()

            res = func(*args,**kargs)

            used = time.time()-start

            #if(used > timeout[0]):  python 2.x

            if(used > timeout):

                msg = '"%s":"%s" > %s' % (func.__name__,used,timeout)

                logging.warn(msg)

            return res

        def setTimeOut(k):

            nonlocal timeout

            timeout = k

            #timeout[0] = k    python 2.x

        wrapper.setTimeOut = setTimeOut

        return wrapper

    return decorator

from random import randint

@warn(1.5)

def test():

    print('in test')

    while randint(0,1):

        time.sleep(0.5)

for _ in range(30):

    test()

test.setTimeOut(1)

for _ in range(30):

    test()

检测带参数类型的函数装饰器

from inspect import signature

def typeassert(*ty_args,**ty_kargs):

    def decorator(func):

        sig = signature(func)

        btypes = sig.bind_partial(*ty_args,**ty_kargs).arguments

        def wrapper(*args,**kargs):

            for name,obj in sig.bind_partial(*args,**kargs).arguments.items():

                if name  in btypes:

                    if not isinstance(obj,btypes[name]):

                        raise TypeError("%s must be %s" % (name,btypes))

            return func(*args,**kargs)

        return wrapper

    return decorator

@typeassert(int,str,list)

def f(a,b,c):

    print(a,b,c)

f(1,'abc',[1,2,3])

f(1,2,[1,2,3])