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Getting a map() to return a list in Python 3.x
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Do this:
list(map(chr,[66,53,0,94]))
In Python 3+, many processes that iterate over iterables return iterators themselves. In most cases, this ends up saving memory, and should make things go faster.
If all you're going to do is iterate over this list eventually, there's no need to even con...
Why is “throws Exception” necessary when calling a function?
...o specify a throws clause for all classes. Specifically, classes that are either an Error or RuntimeException or any of the subclasses of these two. In your case Exception is not a subclass of an Error or RuntimeException. So, it is a checked exception and must be specified in the throws clause, if ...
jQuery - Get Width of Element when Not Visible (Display: None)
It seems like in jQuery when an element is not visible width() returns 0. Makes sense, but I need to get the width of a table in order to set the width of the parent before I show the parent.
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Is multiplication and division using shift operators in C actually faster?
Multiplication and division can be achieved using bit operators, for example
19 Answers
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Check if object is file-like in Python
...objects in Python that behave like a real file, e.g. have a read() and a write method(), but have a different implementation. It is and realization of the Duck Typing concept.
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Is there any overhead to declaring a variable within a loop? (C++)
...laring a variable inside a loop and I was wondering what's wrong until he cited performance as the reason not to do so and I was like "WTF!?".
– Mehrdad Afshari
Jun 11 '09 at 19:35
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Why does C++11's lambda require “mutable” keyword for capture-by-value, by default?
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It requires mutable because by default, a function object should produce the same result every time it's called. This is the difference between an object orientated function and a function using a global variable, effectively...
Collection versus List what should you use on your interfaces?
...s to why not List<T>, The reasons are future-proofing and API simplicity.
Future-proofing
List<T> is not designed to be easily extensible by subclassing it; it is designed to be fast for internal implementations. You'll notice the methods on it are not virtual and so cannot be overridd...
Is it possible to make the -init method private in Objective-C?
I need to hide (make private) the -init method of my class in Objective-C.
9 Answers
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How to place and center text in an SVG rectangle
...y solution to center text horizontally and vertically in SVG:
Set the position of the text to the absolute center of the element in which you want to center it:
If it's the parent, you could just do x="50%" y ="50%".
If it's another element, x would be the x of that element + half its width (and...