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Django: Get an object form the DB, or 'None' if nothing matches
....get(*args, **kwargs)
except model.DoesNotExist:
return None
Call it like this
foo = get_or_none(Foo, baz=bar)
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Javascript switch vs. if…else if…else
...object has a lot of advantages. You can add and remove functionality dynamically. You can create the dispatch table from data. You can examine it programmatically. You can build the handlers with other functions.
There's the added overhead of a function call to get to the equivalent of a "case", bu...
ASP.NET MVC: Custom Validation by DataAnnotation
...r this all morning! I've mplemented it, and unfortunately when IsValid is called the validationContext is null. Any idea what I did wrong? :-(
– Grimm The Opiner
Nov 6 '13 at 12:50
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How to find list of possible words from a letter matrix [Boggle Solver]
Lately I have been playing a game on my iPhone called Scramble. Some of you may know this game as Boggle. Essentially, when the game starts you get a matrix of letters like so:
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How do I create 7-Zip archives with .NET?
... be installed (and in the path) on all target machines, you can offload by calling the command line app 7z. Not the most elegant solution but it is the least work.
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Seeing escape characters when pressing the arrow keys in python shell
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Won't this cause a problem if something calls v6, not realising that it's actually v7?
– Adam Barnes
Feb 24 '17 at 16:05
3
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How to ISO 8601 format a Date with Timezone Offset in JavaScript?
...ies the opposite sign.
Also, there is no method on the native Date object called format, so your function in #1 will fail unless you are using a library to achieve this. Refer to this documentation.
If you are seeking a library that can work with this format directly, I recommend trying moment.js...
How do I Search/Find and Replace in a standard string?
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You are messing a bit with memory here with all the calls to "replace" : complexity would be n² if you remove "o" from "ooooooo...o". I guess one can do better, but this solution has the merit of being easy to understand.
– Zonko
Sep 21 ...
How to view the SQL queries issued by JPA?
When my code issues a call like this:
16 Answers
16
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Parallelize Bash script with maximum number of processes
...e
}
To use it, all one has to do is put & after the jobs and a pwait call, the parameter gives the number of parallel processes:
for i in *; do
do_something $i &
pwait 10
done
It would be nicer to use wait instead of busy waiting on the output of jobs -p, but there doesn't seem ...