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Is there a “null coalescing” operator in JavaScript?
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Update
JavaScript now supports the nullish coalescing operator (??). It returns its right-hand-side operand when its left-hand-side operand is null or undefined, and otherwise returns its left-hand-side operand.
Please check compatibility be...
How do you add a timer to a C# console application
...ram {
public static void Main() {
// Create a Timer object that knows to call our TimerCallback
// method once every 2000 milliseconds.
Timer t = new Timer(TimerCallback, null, 0, 2000);
// Wait for the user to hit <Enter>
Console.ReadLine();
}
private ...
Explain the use of a bit vector for determining if all characters are unique
...d plus it can store more flags.
For future reference: bit vector is also known as bitSet or bitArray. Here are some links to this data structure for different languages/platforms:
CPP: BitSet
Java: BitSet
C#: BitVector32 and BitArray
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How to detect if app is being built for device or simulator in Swift
In Objective-C we can know if an app is being built for device or simulator using macros:
20 Answers
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What is the difference between concurrency and parallelism?
...ery important tasks in one day:
Get a passport
Get a presentation done
Now, the problem is that task-1 requires you to go to an extremely bureaucratic government office that makes you wait for 4 hours in a line to get your passport. Meanwhile, task-2 is required by your office, and it is a criti...
C++ performance vs. Java/C#
...to do all of its heap compression at once (a fairly expensive operation).
Now I can't speak for Java on this next point, but I know that C# for example will actually remove methods and method calls when it knows the body of the method is empty. And it will use this kind of logic throughout your cod...
How do I get the current date in JavaScript?
...It doesn't consider TimezoneOffset. At my time of testing, I was seeking "now" and I got "yesterday". stackoverflow.com/questions/13646446/…
– mickmackusa
Jun 26 '14 at 15:13
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The best way to remove duplicate values from NSMutableArray in Objective-C?
...ded NSOrderedSet to iOS 5 and Mac OS X 10.7. What had been an algorithm is now two lines of code:
NSOrderedSet *orderedSet = [NSOrderedSet orderedSetWithArray:yourArray];
NSArray *arrayWithoutDuplicates = [orderedSet array];
If you are worried about the order and you're running on iOS 4 or earl...
WKWebView not loading local files under iOS 8
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They finally solved the bug! Now we can use -[WKWebView loadFileURL:allowingReadAccessToURL:].
Apparently the fix was worth some seconds in WWDC 2015 video 504 Introducing Safari View Controller
For iOS8 ~ iOS10 (Swift 3)
As Dan Fabulish's answer s...
How to send a message to a particular client with socket.io
I'm starting with socket.io + node.js, I know how to send a message locally and to broadcast socket.broadcast.emit() function:- all the connected clients receive the same message.
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