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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...
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...
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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Why does ++[[]][+[]]+[+[]] return the string “10”?
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If we split it up, the mess is equal to:
++[[]][+[]]
+
[+[]]
In JavaScript, it is true that +[] === 0. + converts something into a number, and in this case it will come down to +"" or 0 (see specification details below).
Therefore...
Where is the C auto keyword used?
... about the auto keyword and in the course of time I actually forgot what it is. It is defined as:
9 Answers
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Should I pass a shared_ptr by reference? [duplicate]
...general, you should pass the shared pointer as a straight copy. This gives it its intended semantics: Every scope that contains a copy of the shared pointer keeps the object alive by virtue of its "share" in the ownership.
The only reason not to always pass by value is that copying a shared pointer...
Why are static variables considered evil?
...n application using Groovy and Java. All through the code I wrote used quite a good number of statics. I was asked by the senior technical lot to cut down on the number of statics used. I've googled about the same, and I find that many programmers are fairly against using static variables.
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