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Is there a benefit to defining a class inside another class in Python?
What I'm talking about here are nested classes. Essentially, I have two classes that I'm modeling. A DownloadManager class and a DownloadThread class. The obvious OOP concept here is composition. However, composition doesn't necessarily mean nesting, right?
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Is generator.next() visible in Python 3?
...son for this is consistency: special methods like __init__() and __del__() all have double underscores (or "dunder" in the current vernacular), and .next() was one of the few exceptions to that rule. This was fixed in Python 3.0. [*]
But instead of calling g.__next__(), use next(g).
[*] There are ...
Dynamic variable names in Bash
...Fgilrtux] [-p] [name[=value] ...]. You might double-check that you are actually running 4.x and not 3.2.
– chepner
Dec 2 '13 at 16:08
5
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HTML5 check if audio is playing?
...t does work and it some not. I guess it depends on implementation. But for all latest updates for chrome and firefox it seems to work, so This answer is correct for latest implementations.
– Tomas
Aug 27 '12 at 4:39
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How to find out what type of a Mat object is with Mat::type() in OpenCV
...";
r += (chans+'0');
return r;
}
If M is a var of type Mat you can call it like so:
string ty = type2str( M.type() );
printf("Matrix: %s %dx%d \n", ty.c_str(), M.cols, M.rows );
Will output data such as:
Matrix: 8UC3 640x480
Matrix: 64FC1 3x2
Its worth noting that there are also Matr...
How do I get the opposite (negation) of a Boolean in Python?
...ful if you want to use a function that requires a predicate-function or a callback.
For example map or filter:
>>> lst = [True, False, True, False]
>>> list(map(operator.not_, lst))
[False, True, False, True]
>>> lst = [True, False, True, False]
>>> list(filter...
What is the difference between old style and new style classes in Python?
...(x) is always <type
'instance'>.
This reflects the fact that all old-style instances, independently of
their class, are implemented with a single built-in type, called
instance.
New-style classes were introduced in Python 2.2 to unify the concepts of class and type.
A new-s...
Is it intended by the C++ standards committee that in C++11 unordered_map destroys what it inserts?
... always move from its argument. It's supposed to move if the argument is really an rvalue, and copy if it's an lvalue.
The behaviour, you observe, which always moves, is a bug in libstdc++, which is now fixed according to a comment on the question. For those curious, I took a look at the g++-4.8 he...
static constructors in C++? I need to initialize private static objects
... to have a class with a private static data member (a vector that contains all the characters a-z). In java or C#, I can just make a "static constructor" that will run before I make any instances of the class, and sets up the static data members of the class. It only gets run once (as the variables ...
disable textbox using jquery?
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This thread is a bit old but the information should be updated.
http://api.jquery.com/attr/
To retrieve and change DOM properties such as the checked, selected,
or disabled state of form elements, use the .prop() method.
$("#radiobutt input[type=radio]").each(function(i){
$(this).click(f...