练习
请设计一个decorator,它可作用于任何函数上,并打印该函数的执行时间:
# -*- coding: utf-8 -*-
import time, functools
def metric(fn):
@functools.wraps(fn)
def wrapper(*args,**kwargs):
t1=time.time()
run=fn(*args, **kwargs)
t2=time.time()
print('%s executed in %s ms' % (fn.__name__,t2-t1))
return run
return wrapper
# 测试
@metric
def fast(x, y):
time.sleep(0.0012)
return x + y;
@metric
def slow(x, y, z):
time.sleep(0.1234)
return x * y * z;
f = fast(11, 22)
s = slow(11, 22, 33)
if f != 33:
print('测试失败!')
elif s != 7986:
print('测试失败!')