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Is there any difference between “foo is None” and “foo == None”?
... Hmmm, I think your link changed, unless you were interested in how to call external functions from python
– Pat
May 4 '12 at 20:39
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Event system in Python
...r methods', which is a
simple implementation of the Observer pattern.
Basically, the handler methods (callables) are stored in an array and are each called when the event 'fires'.
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The disadvantage of Observer event systems is that you can only register the handlers on the actual Ev...
Execution of Python code with -m option or not
...st python -m foo.bar.baz
foo.bar
__main__
As a result, Python has to actually care about packages when using the -m switch. A normal script can never be a package, so __package__ is set to None.
But run a package or module inside a package with -m and now there is at least the possibility of a pac...
How do I raise the same Exception with a custom message in Python?
...ssign a special meaning to the elements of this tuple, while others are usually called only with a single string giving an error message.". So the code won't work arg[0] is not an error message (it could be an int, or it could be a string representing a file name).
– Trent
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Two way/reverse map [duplicate]
...
1
>>> del d['foo']
>>> d['bar']
Traceback (most recent call last):
File "<stdin>", line 7, in <module>
KeyError: 'bar'
I'm sure I didn't cover all the cases, but that should get you started.
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Make a borderless form movable?
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This article on CodeProject details a technique. Is basically boils down to:
public const int WM_NCLBUTTONDOWN = 0xA1;
public const int HT_CAPTION = 0x2;
[System.Runtime.InteropServices.DllImport("user32.dll")]
public static extern int SendMessage(IntPtr hWnd, int Msg, int wParam...
Algorithm to detect corners of paper sheet in photo
...n are awesome, move to them as soon as possible. :D
Instead of removing small objects and or noise, lower the canny restraints, so it accepts more edges, and then find the largest closed contour (in OpenCV use findcontour() with some simple parameters, I think I used CV_RETR_LIST). might still stru...
Unioning two tables with different number of columns
... I realized that this solution also works without having to list all the columns. So instead of Select Col1, Col2, Col3, Null as Col4, Null as Col5 from Table2, one can also do, Select *, Null as Col4, Null as Col5 from Table2.
– Pratik Patel
Sep 20 '...
How do I get the full path to a Perl script that is executing?
...me of the script during execution. I discovered that depending on how you call the script $0 varies and sometimes contains the fullpath+filename and sometimes just filename . Because the working directory can vary as well I can't think of a way to reliably get the fullpath+filename of the scr...
How to read a file into a variable in shell?
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Ok but it's bash, not sh; it may not fit all cases.
– moala
Apr 15 '13 at 11:25
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