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How to map and remove nil values in Ruby
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Ruby 2.7 is introducing filter_map for this exact purpose. It's idiomatic and performant, and I'd expect it to become the norm very soon.
For example:
numbers = [1, 2, 5, 8, 10, 13]
enum.filter_map { |i| i * 2 if i.even? }
# => [4, 16, 20]
In your case, as the block evaluates to falsey, simp...
How to overload std::swap()
std::swap() is used by many std containers (such as std::list and std::vector ) during sorting and even assignment.
4 A...
Why doesn't django's model.save() call full_clean()?
...matic" validation option which is both simple enough to actually be useful and robust enough to handle all the edge cases is -- if it's even possible -- far more than can be accomplished on the 1.2 timeframe. Hence, for now, Django doesn't have any such thing, and won't have it in 1.2. If you think ...
Creating an empty Pandas DataFrame, then filling it?
I'm starting from the pandas DataFrame docs here: http://pandas.pydata.org/pandas-docs/stable/dsintro.html
5 Answers
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Replace all whitespace characters
...u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff]
in Firefox and [ \f\n\r\t\v] in IE.
str = str.replace(/\s/g, "X");
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Random string generation with upper case letters and digits
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Answer in one line:
''.join(random.choice(string.ascii_uppercase + string.digits) for _ in range(N))
or even shorter starting with Python 3.6 using random.choices():
''.join(random.choices(string.ascii_uppercase + string.digits, k=N))
A cryptographi...
Duplicate symbols for architecture x86_64 under Xcode
... Xcode 8 prompted this change as one of its automatic updates and broke my build :/
– pkamb
Oct 7 '16 at 16:18
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How to convert std::string to NSString?
Hi I am trying to convert a standard std::string into an NSString but I'm not having much luck.
6 Answers
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Refused to display in a frame because it set 'X-Frame-Options' to 'SAMEORIGIN'
...d a better solution, maybe it can help somebody
replace "watch?v=" by "v/" and it will work
var url = url.replace("watch?v=", "v/");
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What does the explicit keyword mean?
...hat takes a Foo object:
void DoBar (Foo foo)
{
int i = foo.GetFoo ();
}
and here's where the DoBar function is called:
int main ()
{
DoBar (42);
}
The argument is not a Foo object, but an int. However, there exists a constructor for Foo that takes an int so this constructor can be used to conv...