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private[this] vs private
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This was tested using scala 2.11.5. Consider the code below
class C(private val x: Int) {
override def equals(obj: Any) = obj match {
case other: C => x == other.x
case _ => false
}
}
println(new C(5) == new C(5)) ...
JavaScript: empty array, [ ] evaluates to true in conditional structures. Why is this?
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If you test the expression [] == false it evaluates to true.
– m.rufca
Apr 24 '18 at 18:06
3
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When should I use double or single quotes in JavaScript?
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@Olly Hicks, interesting test!! Single quotes are actually several times faster than double quotes here in Chrome 13 (OSX). Interesting...
– Ricket
Sep 14 '11 at 23:48
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How do I generate random integers within a specific range in Java?
... difficult to reproduce results in situations where that is useful such as testing or saving game states or similar. In those situations, the pre-Java 1.7 technique shown below can be used.
Before Java 1.7, the standard way to do this is as follows:
import java.util.Random;
/**
* Returns a pseu...
Adding a user to a group in django
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Here's how to do this in modern versions of Django (tested in Django 1.7):
from django.contrib.auth.models import Group
group = Group.objects.get(name='groupname')
user.groups.add(group)
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Java's final vs. C++'s const
...s. E.g.:
class Foo {
public:
void bar();
void foo() const;
};
void test(const Foo& i) {
i.foo(); //fine
i.bar(); //error
}
Values can be assigned, once, later in Java only e.g.:
public class Foo {
void bar() {
final int a;
a = 10;
}
}
is legal in Java, but no...
Remove rows with duplicate indices (Pandas DataFrame and TimeSeries)
...-1]
df = df.iloc[ np.unique( df.index.values, return_index = True )[1] ]
Tests: 10k loops using OP's data
numpy method - 3.03 seconds
df.loc[~df.index.duplicated(keep='first')] - 4.43 seconds
df.groupby(df.index).first() - 21 seconds
reset_index() method - 29 seconds
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Setting transparent images background in IrfanView
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Based on my tests, this actually seems to be the easiest and most effective solution to saved icons missing transparency. Just make sure you click "options" like @Annalisa says, and not "Advanced"
– Eric Hepperle - ...
New lines inside paragraph in README.md
...o empty lines are a new paragraph (same as here in stackoverflow)
You can test it with http://prose.io
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Using sed, how do you print the first 'N' characters of a line?
... N+1 characters up to the end of line:
$ sed 's/.//5g' <<< "defn-test"
defn
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