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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
...
Why / when would it be appropriate to override ToString?
I'm studying C# and I wonder what the point and benefit of overriding ToString might be, as shown in the example below.
1...
Haskell Type vs Data Constructor
...alue is expected.
Data constructors
To make things simple, we can start with an example of a type that represents a colour.
data Colour = Red | Green | Blue
Here, we have three data constructors. Colour is a type, and Green is a constructor that contains a value of type Colour. Similarly, Red a...
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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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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Using an HTML button to call a JavaScript function
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There are a few ways to handle events with HTML/DOM. There's no real right or wrong way but different ways are useful in different situations.
1: There's defining it in the HTML:
<input id="clickMe" type="button" value="clickme" onclick="doFunction();" /&g...
How to overload std::swap()
...
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 to show Page Loading div until the page has finished loading?
I have a section on our website that loads quite slowly as it's doing some intensive calls.
12 Answers
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Difference between size_t and unsigned int?
...he internet and everywhere mentioned that size_t is an unsigned type so, it can represent only non-negative values.
7 Ans...
How to truncate a foreign key constrained table?
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You cannot TRUNCATE a table that has FK constraints applied on it (TRUNCATE is not the same as DELETE).
To work around this, use either of these solutions. Both present risks of damaging the data integrity.
Option 1:
Remove constraints
Perform TRUNCATE
Delete manually the rows that n...