Of course there is something to replace nested:
with open("egg.txt","w") as egg, open("spam.txt","w") as spam: egg.write("egg") spam.write("spam")
The nested function was removed because it is broken. E.g. take this:
with nested(open("egg.txt","w"), open("spam.txt","w")) as egg, spam: egg.write("egg") barspamwrite("spam")
What if opening of spam.txt produces an exception? Then egg.txt will never be closed! The new with syntax takes care of this. It basically rewrites it as:
with open("egg.txt","w") as egg: with open("spam.txt","w") as spam: egg.write("egg") spam.write("spam")
On 02/03/2012 04:09 PM, Yury Selivanov wrote:
With the removal of "contextlib.nested" in python 3.2 nothing was introduced to replace it. However, I found it pretty useful, despite the fact that it had its own quirks. These quirks can (at least partially) be addressed by allowing unpacking syntax in the context manager.
Consider the following snipped of code:
ctxs = () if args.profile: ctxs += (ApplicationProfilerContext(),) if args.logging: ctxs += (ApplicationLoggingContext(),) with *ctxs: Application.run()
As of now, without "nested" we have either option of reimplementing it, or to write lots of ugly code with nested 'try..except's. So the feature was taken out, but nothing replaced it.
What do you think guys?
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