使用break时在python生成器中的yield语句之后运行代码
我有一个简单的生成器:
def counter(n):
counter = 0
while counter <= n:
counter += 1
yield counter
print(f"Nice! You counted to {counter}")
def test_counter():
for count in counter(6):
print(f"count={count}")
if count > 3:
break
在这个例子中,当计数达到 3 时有一个中断。但是代码的唯一问题是中断在 yield 语句终止了生成器的执行。它不会在 yield 语句之后运行 print 语句。有没有办法在发生中断时在 yield 语句之后的生成器中执行代码?
示例运行:
# What happens:
>>> test_counter()
count=1
count=2
count=3
count=4
# What I'd like to see:
>>> test_counter()
count=1
count=2
count=3
count=4
Nice! You counted to 4
回答
你必须把它print放在一个finally-block 中:
def counter(n):
try:
counter = 0
while counter <= n:
counter += 1
yield counter
finally:
print(f"Nice! You counted to {counter}")
def test_counter():
for count in counter(6):
print(f"count={count}")
if count > 3:
break