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Uses for Optional
Having been using Java 8 now for 6+ months or so, I'm pretty happy with the new API changes. One area I'm still not confident in is when to use Optional . I seem to swing between wanting to use it everywhere something may be null , and nowhere at all.
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How to convert an Int to a String of a given length with leading zeros to align?
... when I posted the initial answer, but I would also use the f interpolator now that it exists.
– huynhjl
Aug 8 '13 at 13:11
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Is pass-by-value a reasonable default in C++11?
... void foo(T const&); and void foo(T&&);.
With that in mind, I now wrote my valued constructors as such:
class T {
U u;
V v;
public:
T(U u, V v)
: u(std::move(u))
, v(std::move(v))
{}
};
Otherwise, passing by reference to const still is reasonable.
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In JavaScript, why is “0” equal to false, but when tested by 'if' it is not false by itself?
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From now on, if someone says that he never uses strict comparison operators, I will face him with these tables and make him cry. Still not sure if I grasp the concept of NaN though. I mean, typeof NaN // number but NaN === NaN //...
Go to beginning of line without opening new line in VI
For ages now I've used SHIFT O and SHIFT $ to move to the beginning and end of a line in vi .
10 Answers
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Select2 dropdown but allow new values by user?
...taken from an answer on the select2 mailing list, but cannot find the link now)
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Why should I use the keyword “final” on a method parameter in Java?
... );
void doSomething( String arg ) {
String x = arg; // Both variables now point to the same String object.
x = "elephant"; // This variable now points to a different String object.
arg = "giraffe"; // Ditto. Now neither variable points to the original passed String.
}
Mark the local va...
python pandas: apply a function with arguments to a series
...andas do allow you to pass extra arguments (see the new documentation). So now you can do:
my_series.apply(your_function, args=(2,3,4), extra_kw=1)
The positional arguments are added after the element of the series.
For older version of pandas:
The documentation explains this clearly. The app...
git-svn: how do I create a new svn branch via git?
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I know this question has been answered a while ago, but after reading it, I it might help adding examples of the specific git svn branch command and relate it to a typical workflow.
Like kch answered, use git svn branch. Here i...
Understanding generators in Python
...u do not look into until you understand the basic concept of a generator.
Now you may ask: why use generators? There are a couple of good reasons:
Certain concepts can be described much more succinctly using generators.
Instead of creating a function which returns a list of values, one can write ...