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How can a Java variable be different from itself?
...same with Double.NaN.
From JLS §15.21.1. Numerical Equality Operators == and !=:
Floating-point equality testing is performed in accordance with the rules of the IEEE 754 standard:
If either operand is NaN, then the result of == is false but the result of != is true.
Indeed, the test x!=x is tru...
How do I prompt a user for confirmation in bash script? [duplicate]
... do dangerous stuff
fi
I incorporated levislevis85's suggestion (thanks!) and added the -n option to read to accept one character without the need to press Enter. You can use one or both of these.
Also, the negated form might look like this:
read -p "Are you sure? " -n 1 -r
echo # (optional) mov...
visual studio not remembering open documents & startup project
For the past week, something has changed about my VS solution, and I havent found a setting to fix it yet.
16 Answers
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How many and which are the uses of “const” in C++?
...y obscure to me, one of these is const . You can use it in so many places and with so many different effects that is nearly impossible for a beginner to come out alive. Will some C++ guru explain once forever the various uses and whether and/or why not to use them?
...
Is key-value observation (KVO) available in Swift?
...mework can help you accomplish what you wanted, rather than using KVO
Yes and no. KVO works on NSObject subclasses much as it always has. It does not work for classes that don't subclass NSObject. Swift does not (currently at least) have its own native observation system.
(See comments for how to ...
“unrecognized selector sent to instance” error in Objective-C
I created a button and added an action for it, but as soon as it invoked, I got this error:
38 Answers
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How to check if any flags of a flag combination are set?
...f you want to know if letter has any of the letters in AB you must use the AND & operator. Something like:
if ((letter & Letters.AB) != 0)
{
// Some flag (A,B or both) is enabled
}
else
{
// None of them are enabled
}
...
Mixins vs. Traits
What is the difference between Mixins and Traits?
2 Answers
2
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Usage of EnsureSuccessStatusCode and handling of HttpRequestException it throws
...sage.EnsureSuccessStatusCode() ? It disposes of the Content of the message and throws HttpRequestException , but I fail to see how to programmatically handle it any differently than a generic Exception . For example, it doesn't include the HttpStatusCode , which would have been handy.
...
Is Javascript a Functional Programming Language?
Just because functions are first class objects, there are closures, and higher order functions, does Javascript deserve to be called a Functional Programming language? The main thing I think it lacks is Pure Functions, and it doesn't 'feel' like other functional languages, like lisp (although thats...