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What reason is there to use null instead of undefined in JavaScript?
...s undefined.
Which is why in my code I never use null unless something I don't control returns null (regex matching for example). The beauty of this is it simiplifies things a lot. I never have to check if x === undefined || x === null. And if you're in the habit of using == or simply stuff like i...
What is the right way to check for a null string in Objective-C?
...nder Cocoa/Objective C. But one further thing to note is that [title isKindOfClass:[NSNull class]] is pointlessly complex since [NSNull null] is documented to be a singleton so you can just check for pointer equality. See Topics for Cocoa: Using Null.
So a good test might be:
if (title == (id)[NS...
C++ deprecated conversion from string constant to 'char*'
... const correctness. But the code you showed to us is not the problem as it does not do this kind of deprecated conversion. The warning must have come from some other place.
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Inheritance vs. Aggregation [closed]
...we need almost all of the functionality without major changes. And when in doubt, use Aggregation.
An other possibility for, the case that we have an class that needs part of the functionality of the original class, is to split the original class in a root class and a sub class. And let the new cla...
What are the Ruby Gotchas a newbie should be warned about? [closed]
...cal variables should begin with a lowercase letter.
The characters $ and @ do not indicate variable data type as in Perl, but rather function as scope resolution operators.
To denote floating point numbers, one must follow with a zero digit (99.0) or an explicit conversion (99.to_f). It is insuffici...
How can I change an element's class with JavaScript?
...ethods to make it easier to manipulate classes without needing a library:
document.getElementById("MyElement").classList.add('MyClass');
document.getElementById("MyElement").classList.remove('MyClass');
if ( document.getElementById("MyElement").classList.contains('MyClass') )
document.getElement...
What do I return if the return type of a method is Void? (Not void!)
...od with this signature. Consider carefully whether there's a better way to do what you want (perhaps you can provide more details in a different, follow-up question?). I'm a little suspicious, since this only came up "due to the use of generics".
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How do you get the magnitude of a vector in Numpy?
In keeping with the "There's only one obvious way to do it", how do you get the magnitude of a vector (1D array) in Numpy?
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EC2 Instance Cloning
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How do I do that?
– Josh Scott
Feb 2 '10 at 4:27
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How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
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does anyone else find it strange that "000" == "0000" ?
– nickf
Sep 17 '08 at 13:08
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