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Referring to the null object in Python
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SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
ASP.NET Web API Authentication
...on while using the ASP.NET Web API . I have watched all the videos on the site and also read this forum post .
3 Answers
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jQuery: How can i create a simple overlay?
How can I create a really basic overlay in jQuery without UI?
7 Answers
7
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Semantic Issue: Property's synthesized getter follows Cocoa naming convention for returning 'owned'
... the memory management rules for declared properties, too — more specifically, for declared properties’ accessors:
You take ownership of an object if you create it using a method whose name begins with “alloc”, “new”, “copy”, or “mutableCopy”.
A property named newTitle, whe...
Python constructor and default value [duplicate]
...class below, the wordList and adjacencyList variable is shared between all instances of Node.
4 Answers
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Drawing Isometric game worlds
...rect, complete one. However, I combined his hints with those from another site to create code that works in my app (iOS/Objective-C), which I wanted to share with anyone who comes here looking for such a thing. Please, if you like/up-vote this answer, do the same for the originals; all I did was "...
Unknown file type MIME?
...e file if the "Content-Disposition" wasn't set, but there are too many web sites haphazardly downloading files without setting their filename to use. Especially banks.
– justdan23
May 15 '19 at 15:35
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How do I get Windows to go as fast as Linux for compiling C++?
...e made technical decisions that they made; but this is a technical Q&A site. Answers should cover the technical reasons why one system is slower than the other (and what can be done to improve the situation), not unprovable conjectures about culture.
– Brian Campbell
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Mongoose, Select a specific field with find
... I think .select just is a filter to choose field after you get all of that, my recommendation is to use .find({}, 'name -_id')
– hong4rc
Mar 2 '19 at 16:15
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SQLAlchemy: cascade delete
...use that is where you defined your relationship (it doesn't care that you called it "Child" of course).
If you define the relationship on the Parent class instead, it will work:
children = relationship("Child", cascade="all,delete", backref="parent")
(note "Child" as a string: this is allowed wh...