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Correct way to use get_or_create?
...f the fields have to be included in defaults. In case CREATE event occurs, all the fields are taken into consideration.
It looks like you need to be returning into a tuple, instead of a single variable, do like this:
customer.source,created = Source.objects.get_or_create(name="Website")
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How to serialize a TimeSpan to XML
I am trying to serialize a .NET TimeSpan object to XML and it is not working. A quick google has suggested that while TimeSpan is serializable, the XmlCustomFormatter does not provide methods to convert TimeSpan objects to and from XML.
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Is there a way to iterate over a dictionary?
...ere you need a key in order to get a value . But how can I iterate over all keys and values in a NSDictionary , so that I know what keys there are, and what values there are? I know there is something called a for-in-loop in JavaScript . Is there something similar in Objective-C ?
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How to delete last item in list?
...this program that calculates the time taken to answer a specific question, and quits out of the while loop when answer is incorrect, but i want to delete the last calculation, so i can call min() and it not be the wrong time, sorry if this is confusing.
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presentViewController:animated:YES view will not appear until user taps again
...ith presentViewController:animated:completion . What I'm making is essentially a guessing game.
8 Answers
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How do I cast a variable in Scala?
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The preferred technique is to use pattern matching. This allows you to gracefully handle the case that the value in question is not of the given type:
g match {
case g2: Graphics2D => g2
case _ => throw new ClassCastException
}
This block replicates the semantics of th...
Set focus on TextBox in WPF from view model
...ample? Is it a TextBox control? If yes, then you are on a wrong way. Generally speaking it's not a good idea to have any reference to UI in your ViewModel. You can ask "Why?" but this is another question to post on Stackoverflow :).
The best way to track down issues with Focus is... debugging .Net ...
Django filter versus get for single object?
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get() is provided specifically for this case. Use it.
Option 2 is almost precisely how the get() method is actually implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're vio...
pip issue installing almost any library
I have a difficult time using pip to install almost anything. I'm new to coding, so I thought maybe this is something I've been doing wrong and have opted out to easy_install to get most of what I needed done, which has generally worked. However, now I'm trying to download the nltk library, and neit...
How to get the current time in milliseconds from C in Linux?
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(intmax_t)s, ms);
}
If your goal is to measure elapsed time, and your system supports the "monotonic clock" option, then you should consider using CLOCK_MONOTONIC instead of CLOCK_REALTIME.
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