用类作为装饰器

练习一

最初代码

class bol(object):  def __init__(self, func):    self.func = func      def __call__(self):    return "{}".format(self.func())class ita(object):  def __init__(self, func):    self.func = func      def __call__(self):    return "{}".format(self.func())@bol@itadef sayhi():  return 'hi'

改进一

class sty(object):  def __init__(self, tag):    self.tag = tag      def __call__(self, f):    def wraper():      return "<{tag}>{res}
     ".format(res=f(), tag=self.tag)    return wraper@sty('b')@sty('i')def sayhi():  return 'hi'

改进二

class sty(object):  def __init__(self, *tags):    self.tags = tags      def __call__(self, f):    def wraper():      n = len(self.tags)      return "{0}{1}{2}".format(('<{}>'*n).format(*self.tags), f(), ('
     '*n).format(*reversed(self.tags)))    return wraper@sty('b', 'i')def sayhi():  return 'hi'  print(sayhi())

改进三

class sty(object):  def __init__(self, *tags):    self.tags = tags      def __call__(self, f):    def wraper(*args, **kwargs):      n = len(self.tags)      return "{0}{1}{2}".format(('<{}>'*n).format(*self.tags), f(*args, **kwargs), ('
     '*n).format(*reversed(self.tags)))    return wraper@sty('b', 'i')def say(word='Hi'):  return word  print(say())print(say('Hello'))

练习二

最初代码

import threadingimport timeclass DecoratorClass(object):    def __init__(self):        self.thread = None    def __call__(self, func, *args, **kwargs):        def wrapped_func(*args, **kwargs):            curr_thread = threading.currentThread().getName()            self.thread = curr_thread            print('\nthread name before running func:', self.thread)            ret_val = func()            print('\nthread name after running func:', self.thread)            return ret_val        return wrapped_func@DecoratorClass()def decorated_with_class():    print('running decorated w class')    time.sleep(1)    returnthreads = []for i in range(5):    t = threading.Thread(target=decorated_with_class)    threads.append(t)    t.setDaemon(True)   # 守护    t.start()

改进：进程锁

import threadingimport timeclass DecoratorClass(object):    def __init__(self):        self.thread = None        self.lock = threading.Lock()    def __call__(self, func, *args, **kwargs):        def wrapped_func(*args, **kwargs):            self.lock.acquire()            curr_thread = threading.currentThread().getName()            self.thread = curr_thread            print('thread name before running func:', self.thread)            ret_val = func()            print('\nthread name after running func:', self.thread)                        self.lock.release()            return ret_val        return wrapped_func@DecoratorClass()def decorated_with_class():    print('Let me sleep 1 second...')    time.sleep(1)    returnthreads = []for i in range(5):    t = threading.Thread(target=decorated_with_class)    threads.append(t)    t.start()