我試圖運行此代碼:隨着語句設置變量無
class A:
def __enter__(self):
print "enter"
def __exit__(self, *args):
print "exit"
def __init__(self, i):
self.i = i
with A(10) as a:
print a.i
而且我得到這個錯誤:
enter
exit
Traceback (most recent call last):
File ".last_tmp.py", line 9, in <module>
print a.i
AttributeError: 'NoneType' object has no attribute 'i'
什麼是錯我的語法?