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When would anyone use a union? Is it a remnant from the C-only days?
I have learned but don't really get unions. Every C or C++ text I go through introduces them (sometimes in passing), but they tend to give very few practical examples of why or where to use them. When would unions be useful in a modern (or even legacy) case? My only two guesses would be programming ...
Mock vs MagicMock
My understanding is that MagicMock is a superset of Mock that automatically does "magic methods" thus seamlessly providing support for lists, iterations and so on... Then what is the reason for plain Mock existing? Isn't that just a stripped down version of MagicMock that can be practically ...
Why is “if not someobj:” better than “if someobj == None:” in Python?
...a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero.
Otherwise, if the object has a __len__ special method (as do container built-ins, li...
Django select only rows with duplicate field values
... syntax is also how Django interprets you wanting to do a join. So, essentially when you try to filter on that, Django thinks you're trying to do a join with count which obviously doesn't exist. The fix is to specify a name for your annotation result, i.e. annotate(mycount=Count('id')) and then filt...
How can I use PowerShell with the Visual Studio Command Prompt?
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Stealing liberally from here: http://allen-mack.blogspot.com/2008/03/replace-visual-studio-command-prompt.html, I was able to get this to work. I added the following to my profile.ps1 and all is well with the world.
pushd 'c:\Program Fil...
What's the difference between dynamic (C# 4) and var?
...iteLine(s.Length);
and
string s = "abc";
Console.WriteLine(s.Length);
All that happened was that the compiler figured out that s must be a string (from the initializer). In both cases, it knows (in the IL) that s.Length means the (instance) string.Length property.
dynamic is a very different b...
How to get everything after a certain character?
...te fast.
$s = '233718_This_is_a_string';
$firstPart = strtok( $s, '_' );
$allTheRest = strtok( '' );
Empty string like this will force the rest of the string to be returned.
NB if there was nothing at all after the '_' you would get a FALSE value for $allTheRest which, as stated in the document...
NuGet for solutions with multiple projects
...ager > Manage NuGet Packages for Solution...
And if you go to the Installed packages area you can 'Manage' a single package across every project in the solution.
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What is the difference between C# and .NET?
.... The C# specification says only a very little about the environment (basically, that it should contain some types such as int, but that's more or less all).
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In-memory size of a Python structure
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Yep. The "4 higher" actually mostly look like "rounding up to a multiple of 8" which I believe is correct for the way malloc behaves here. No idea why decimal gets so distorted (with pympler on 2.6, too).
– Alex Martelli
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