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How do I migrate a model out of one django app and into a new one?
... that one of these models should be in a separate app. I do have south installed for migrations, but I don't think this is something it can handle automatically. How can I migrate one of the models out of the old app into a new one?
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~x + ~y == ~(x + y) is always false?
...=> -1 == -2
Hence, a contradiction. Therefore, ~(x+y) != ~x + ~y for all x and y (mod 2n).
*It is interesting to note that on a machine with one's complement arithmetic, the equality actually holds true for all x and y. This is because under one's complement, ~x = -x. Thus, ~x + ~y == -x + ...
std::function and std::bind: what are they, and when should they be used?
...nd to get g:
auto g = bind(f, _1, 4, _2);
This is more concise than actually writing a functor class to do it.
There are further examples in the article you link to. You generally use it when you need to pass a functor to some algorithm. You have a function or functor that almost does the job yo...
Is there a TRY CATCH command in Bash
... writing a shell script and need to check that a terminal app has been installed. I want to use a TRY/CATCH command to do this unless there is a neater way.
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Django: How to completely uninstall a Django app?
What is the procedure for completely uninstalling a Django app, complete with database removal?
5 Answers
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Explain the concept of a stack frame in a nutshell
... edited Mar 9 at 8:50
virmis_007
14522 silver badges1717 bronze badges
answered Oct 18 '16 at 11:04
Aadity...
namedtuple and default values for optional keyword arguments
...lds)
>>> Node()
Node(val=None, left=None, right=None)
Order
In all versions of Python, if you set fewer default values than exist in the namedtuple, the defaults are applied to the rightmost parameters. This allows you to keep some arguments as required arguments.
>>> Node.__ne...
How do I find where an exception was thrown in C++?
I have a program that throws an uncaught exception somewhere. All I get is a report of an exception being thrown, and no information as to where it was thrown. It seems illogical for a program compiled to contain debug symbols not to notify me of where in my code an exception was generated.
...
Determining Referer in PHP
...s the most reliable and secure way to determine what page either sent, or called (via AJAX), the current page. I don't want to use the $_SERVER['HTTP_REFERER'] , because of the (lack of) reliability, and I need the page being called to only come from requests originating on my site.
Edit: I am...
PEP 8, why no spaces around '=' in keyword argument or a default parameter value?
...
I guess that it is because a keyword argument is essentially different than a variable assignment.
For example, there is plenty of code like this:
kw1 = some_value
kw2 = some_value
kw3 = some_value
some_func(
1,
2,
kw1=kw1,
kw2=kw2,
kw3=kw3)
As you see, it mak...