Mongoengine: How to determine an empty list in MongoEngine?

[candycrusher]

I have a field like this in a MongoDB table: "answers":[]

How can I do conditional branch if I want to know it is an empty list?

I'm using Python 2.7 and MongoEngine 0.15.0.

This is what I am trying to do: if object_name.answer is None:

Is that correct? Please point out if I am on the right track.

[bagerard]

Unless I'm misunderstanding the question, this is a general python question (unless you are asking for how to query through mongoengine).

It all depends:

• If you don't mind whether it is None or [] (or anything else that evaluates to False) you can simply:

if object_name.answer:
    ...

• If you need to separate the None from the empty list:

if object_name.answer == []:
   ...
elif object_name.answer is None:
    ...

[bagerard]

@candycrusher does that answer your question? If yes, then let's close this :)

[JohnAD]

Not to nitpick, but for future readers, I suspect you meant to quote:

if not object_name.answer:
    ...

I suspect most folks would have figured that out, but just in case...

[candycrusher]

@candycrusher does that answer your question? If yes, then let's close this :)

Yes, absolutely did. I appreciate your help. Also, I would like to keep my pace to contribute to open source someday. The web greatwall in China makes me very hard to climb finally to here.

[candycrusher]

Not to nitpick, but for future readers, I suspect you meant to quote:

if not object_name.answer:
    ...

I suspect most folks would have figured that out, but just in case...

Exactly, that's what I need to note and keep this good habit.