python：装饰器

装饰器简介：

@decorator
class C：pass

'''
等于
'''

C = decorator(C)

 

最简单的装饰器函数，写一个计时器

import time
def timer(fu):
      def insfnc():
            strat = time.clock()
            fu()
            end = time.clock()
            print('\n',strat,end)
            print('usetime : %r'%(end-strat))
      return insfnc

@timer           #@time ==  “fnc = timer(fnc) ”
def fnc():
      for i in range(200):
            print(i,end='=')
'''
fnc = timer(fnc)
'''
fnc()