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Set Django IntegerField by choices=… name
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Really like the Encapsulation section on the blog.
– Nathan Keller
Mar 3 '13 at 21:57
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What are the applications of binary trees?
...ningless - they are not a data structure, but a family of data structures, all with different performance characteristics. While it is true that unbalanced binary trees perform much worse than self-balancing binary trees for searching, there are many binary trees (such as binary tries) for which "b...
How to duplicate sys.stdout to a log file?
...est way to accomplish logging when a python app is making a lot of system calls?
17 Answers
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Parse JSON String into a Particular Object Prototype in JavaScript
...olution below that applies Object.assign(..) recursively that can automatically resolve properties (with a bit of information provided in advance)
– vir us
Dec 8 '17 at 16:13
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C++ preprocessor __VA_ARGS__ number of arguments
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This is actually compiler dependent, and not supported by any standard.
Here however you have a macro implementation that does the count:
#define PP_NARG(...) \
PP_NARG_(__VA_ARGS__,PP_RSEQ_N())
#define PP_NARG_(...) \
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What does $_ mean in PowerShell?
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This is the variable for the current value in the pipe line, which is called $PSItem in Powershell 3 and newer.
1,2,3 | %{ write-host $_ }
or
1,2,3 | %{ write-host $PSItem }
For example in the above code the %{} block is called for every value in the array. The $_ or $PSItem variable ...
How can I maintain fragment state when added to the back stack?
... back stack. However, when I return to FragmentA (by pressing back), a totally new FragmentA is created and the state it was in is lost. I get the feeling I'm after the same thing as this question, but I've included a complete code sample to help root out the issue:
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Check if OneToOneField is None in Django
... Thank you for this solution. Unfortunately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasat...
In Flux architecture, how do you manage Store lifecycle?
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In a Flux app there should only be one Dispatcher. All data flows through this central hub. Having a singleton Dispatcher allows it to manage all Stores. This becomes important when you need Store #1 update itself, and then have Store #2 update itself based on both the Acti...
What is the most efficient way to store a list in the Django models?
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This is probably what I will end up doing, but I was really hoping the underlying structure for this would have been built in. I guess I am to o lazy.
– grieve
Jul 10 '09 at 16:11
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