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Django using get_user_model vs settings.AUTH_USER_MODEL
...s.AUTH_USER_MODEL will delay the retrieval of the actual model class until all apps are loaded. get_user_model will attempt to retrieve the model class at the moment your app is imported the first time.
get_user_model cannot guarantee that the User model is already loaded into the app cache. It mi...
Why does scanf() need “%lf” for doubles, when printf() is okay with just “%f”?
...cross-use" %lf with float or %f with double.
But there's no reason to actually do it in practice. Don't use %f to printf arguments of type double. It is a widespread habit born back in C89/90 times, but it is a bad habit. Use %lf in printf for double and keep %f reserved for float arguments.
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CSS does the width include the padding?
...width: 10em; padding: 2em; border: 1em; }
would be 10em wide.
In contrast, all standards-fearing browsers default to the "content-box" box model. In this model, the width of an element does not include padding or borders. For example:
#foo { width: 10em; padding: 2em; border: 1em; }
will actually be...
Checking length of dictionary object [duplicate]
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What I do is use Object.keys() to return a list of all the keys and then get the length of that
Object.keys(dictionary).length
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How persistent is localStorage?
I'm depending heavily on localStorage for a plugin I'm writing. All the user settings are stored in it. Some settings require the user the write regex'es and they would be sad if their regex rules are gone at some point.
So now I am wondering just how persistent the localStorage is.
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How to store arrays in MySQL?
...raberry"
2 | "banana"
2 | "apple"
When you want to retrieve a person and all of their fruit you can do something like this:
SELECT p.*, f.*
FROM person p
INNER JOIN person_fruit pf
ON pf.person_id = p.id
INNER JOIN fruits f
ON f.fruit_name = pf.fruit_name
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Unpacking array into separate variables in JavaScript
...nd I've done it before. I just can't remember how, or what exactly it was called.
7 Answers
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How can I output UTF-8 from Perl?
...sults. I'm using Mac OS X 10.5 (Leopard), and I'm editing with TextMate. All of my settings for both my editor and operating system are defaulted to writing files in utf-8 format.
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Visual Studio 2012 Express is suddenly “incompatible with this version of Windows”?
...e same message on Visual Studio 2012 Premium (on PC where Windows 7 re-installed in last month) - the suggested fix was "Update for Microsoft Visual Studio 2012 (KB2781514)" which seems to have fixed it
www.microsoft.com/en-us/download/details.aspx?id=36020
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Why do C and C++ compilers allow array lengths in function signatures when they're never enforced?
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It is a quirk of the syntax for passing arrays to functions.
Actually it is not possible to pass an array in C. If you write syntax that looks like it should pass the array, what actually happens is that a pointer to the first element of the array is passed instead.
Since the pointer does...