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Type Checking: typeof, GetType, or is?
...runtime type of an instance.
is returns true if an instance is in the inheritance tree.
Example
class Animal { }
class Dog : Animal { }
void PrintTypes(Animal a) {
Console.WriteLine(a.GetType() == typeof(Animal)); // false
Console.WriteLine(a is Animal); // true
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How to overload std::swap()
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The right way to overload swap is to write it in the same namespace as what you're swapping, so that it can be found via argument-dependent lookup (ADL). One particularly easy thing to do is:
class X
{
// ...
friend void swap(X& a, X& b)
{
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How can I add an empty directory to a Git repository?
How can I add an empty directory (that contains no files) to a Git repository?
35 Answers
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Is gettimeofday() guaranteed to be of microsecond resolution?
I am porting a game, that was originally written for the Win32 API, to Linux (well, porting the OS X port of the Win32 port to Linux).
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Is it a good practice to use try-except-else in Python?
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"I do not know if it is out of ignorance, but I do not like that
kind of programming, as it is using exceptions to perform flow control."
In the Python world, using exceptions for flow control is common and normal.
Even the Python core de...
Can someone explain mappedBy in JPA and Hibernate?
...am new to hibernate and need to use one-to-many and many-to-one relations. It is a bi-directional relationship in my objects, so that I can traverse from either direction. mappedBy is the recommended way to go about it, however, I couldn't understand it. Can someone explain:
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What exactly do “IB” and “UB” mean?
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IB: Implementation-defined Behaviour. The standard leaves it up to the particular compiler/platform to define the precise behaviour, but requires that it be defined.
Using implementation-defined behaviour can be useful, but makes your code less portable.
UB: Undefined Behaviour. T...
How can I determine whether a 2D Point is within a Polygon?
I'm trying to create a fast 2D point inside polygon algorithm, for use in hit-testing (e.g. Polygon.contains(p:Point) ). Suggestions for effective techniques would be appreciated.
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Const in JavaScript: when to use it and is it necessary?
...ently come across the const keyword in JavaScript. From what I can tell, it is used to create immutable variables , and I've tested to ensure that it cannot be redefined (in Node.js):
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SVN 405 Method Not Allowed
I accidentally deleted a folder in SVN and added it back immediately. I ran into an issue with this and my solution ended up removing the folder completely from my local copy as well as the server copy. I can do updates and commits without problems on any other file or folder, but if I try to create...