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if A vs if A is not None:
...
The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...
What should be the values of GOPATH and GOROOT?
I'm trying to install doozer like this:
18 Answers
18
...
View not attached to window manager crash
...S will destroy an activity as soon as it is hidden. When onPostExecute is called the Activity will be in "finishing" state and the ProgressDialog will be not attached to Activity.
How to fix it:
Check for the activity state in your onPostExecute method.
Dismiss the ProgressDialog in onDestroy me...
When to use setAttribute vs .attribute= in JavaScript?
...
This answer is not clear enough...I don't really feel I understand this yet.
– temporary_user_name
Oct 24 '13 at 21:48
1
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how to break the _.each function in underscore.js
...t provide to escape the loop (other than throwing an exception).
However, all hope is not lost! You can use the Array.every method. :)
From that link:
every executes the provided callback function once for each element present in the array until it finds one where callback returns a false valu...
What it the significance of the Javascript constructor property?
...the constructor property is used in a few places. However, I think the overall gist still applies. Thanks to T. J. Crowder for pointing that out in the comments, and please read his answer for a fuller picture of the current situation.
Original answer
The constructor property makes absolutely no pra...
Pan & Zoom Image
... tt.X = origin.X - v.X;
tt.Y = origin.Y - v.Y;
}
}
Finally don't forget to release the mouse capture.
private void image_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
image.ReleaseMouseCapture();
}
As for the selection handles for resizing this can be accompl...
Best practice for Python assert
...
To be able to automatically throw an error when x become less than zero throughout the function. You can use class descriptors. Here is an example:
class LessThanZeroException(Exception):
pass
class variable(object):
def __init__(self, va...
Pandas selecting by label sometimes return Series, sometimes returns DataFrame
...answered Dec 4 '13 at 19:36
Dan AllanDan Allan
27.4k66 gold badges6060 silver badges6060 bronze badges
...
python multithreading wait till all threads finished
...oin method of Thread object in the end of the script.
t1 = Thread(target=call_script, args=(scriptA + argumentsA))
t2 = Thread(target=call_script, args=(scriptA + argumentsB))
t3 = Thread(target=call_script, args=(scriptA + argumentsC))
t1.start()
t2.start()
t3.start()
t1.join()
t2.join()
t3.join...