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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")
...
C++ templates that accept only certain types
...ply forward-declare a global template, but only define (explicitly or partially specialise) it for the valid types:
template<typename T> class my_template; // Declare, but don't define
// int is a valid type
template<> class my_template<int> {
...
};
// All pointer types...
How does HTTP file upload work?
...?) always threaded so that they can handle concurrent connections. Essentially, the daemon process that's listening on port 80 immediately hands off the task of serving to another thread/process in order that it can return to listening for another connection; even if two incoming connections arrive...
TypeScript function overloading
...use, when both functions are compiled to JavaScript, their signature is totally identical. As JavaScript doesn't have types, we end up creating two functions taking same number of arguments. So, TypeScript restricts us from creating such functions.
TypeScript supports overloading based on number of...
Matplotlib - Move X-Axis label downwards, but not X-Axis Ticks
...
If the variable ax.xaxis._autolabelpos = True, matplotlib sets the label position in function _update_label_position in axis.py according to (some excerpts):
bboxes, bboxes2 = self._get_tick_bboxes(ticks_to_draw, renderer)
bbox = mtransforms...
How to use dashes in HTML-5 data-* attributes in ASP.NET MVC
...an underscore.
For example:
@Html.TextBoxFor(vm => vm.City, new { data_bind = "foo" })
will render this in MVC 3:
<input data-bind="foo" id="City" name="City" type="text" value="" />
If you're still using an older version of MVC, you can mimic what MVC 3 is doing by creating this sta...
Why git can't remember my passphrase under Windows
...msysgit or not.
First solution Assumes Windows, msysgit, and PuTTY.
Install msysgit and PuTTY as instructed.
(Optional) Add PuTTY to your path. (If you do not do this, then any references to PuTTY commands below must be prefixed with the full path to the appropriate executable.)
If you have not d...
TransformXml task could not be loaded from Microsoft.Web.Publishing.Tasks.dll
...dio 2012.
For VS 2013 this fails as well. In order to make this work with all versions of Visual Studio you should:
Open the project file (.csproj) of the project failing to load
Search for <Import Project="$(MSBuildExtensionsPath)\Microsoft\VisualStudio\v10.0\Web\Microsoft.Web.Publishing.tar...
Debug Error \"pure virtual function call\" 原因解析 - 更多技术 - 清泛...
...
public:
virtual void virtualFunc(){}
};
Base* pB = new Derived;
__try
{
delete pB; // . . . b)
pB = NULL;
}
__except(EXCEPTION_EXECUTE_HANDLER){
}
pB->virtualFunc(); // . . . c)
在b)处析构Derived对象的时候，在其基类析构函数中a)处抛出了...
Proper SCSS Asset Structure in Rails
...
The problem with CSS is, you do not want to automatically add all files.
The order of which your sheets are loaded and processed by the browser is essential. So you will always end up explicitly importing all your css.
As an example, lets say you have a normalize.css sheet, t...