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C# - Keyword usage virtual+override vs. new
...w method that has nothing to do with the base class method.
public class Foo
{
public bool DoSomething() { return false; }
}
public class Bar : Foo
{
public new bool DoSomething() { return true; }
}
public class Test
{
public static void Main ()
{
Foo test = new Bar ();...
Is there any difference between “foo is None” and “foo == None”?
...is ultimately determined by the __eq__() method
i.e.
>>> class Foo(object):
def __eq__(self, other):
return True
>>> f = Foo()
>>> f == None
True
>>> f is None
False
...
Getting an element from a Set
...to use the iterator:
public static void main(String[] args) {
Set<Foo> set = new HashSet<Foo>();
set.add(new Foo("Hello"));
for (Iterator<Foo> it = set.iterator(); it.hasNext(); ) {
Foo f = it.next();
if (f.equals(new Foo("Hello")))
System...
Can I call a constructor from another constructor (do constructor chaining) in C++?
...legating constructors).
The syntax is slightly different from C#:
class Foo {
public:
Foo(char x, int y) {}
Foo(int y) : Foo('a', y) {}
};
C++03: No
Unfortunately, there's no way to do this in C++03, but there are two ways of simulating this:
You can combine two (or more) constructors v...
How can I join elements of an array in Bash?
...y , a "b c" d #a,b c,d
join_by / var local tmp #var/local/tmp
join_by , "${FOO[@]}" #a,b,c
This solution is based on Pascal Pilz's original suggestion.
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What is “lifting” in Haskell?
...
Typically you have some data type with a parameter. Something like
data Foo a = Foo { ...stuff here ...}
Suppose you find that a lot of uses of Foo take numeric types (Int, Double etc) and you keep having to write code that unwraps these numbers, adds or multiplies them, and then wraps them bac...
Getters \ setters for dummies
...properties. They work with all modern browsers except IE 8 and below.
var foo = {
bar : 123,
get bar(){ return bar; },
set bar( value ){ this.bar = value; }
};
foo.bar = 456;
var gaz = foo.bar;
Custom Getters and Setters
get and set aren't reserved words, so they can be overloaded to...
Is it possible to clone html element objects in JavaScript / JQuery?
...n copy children of one element and paste them into the other element:
var foo1 = jQuery('#foo1');
var foo2 = jQuery('#foo2');
foo1.html(foo2.children().clone());
Proof: http://jsfiddle.net/de9kc/
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What is the 'override' keyword in C++ used for? [duplicate]
...errides.
To explain the latter:
class base
{
public:
virtual int foo(float x) = 0;
};
class derived: public base
{
public:
int foo(float x) override { ... } // OK
}
class derived2: public base
{
public:
int foo(int x) override { ... } // ERROR
};
In derived2 the compi...
What are some (concrete) use-cases for metaclasses?
...ase classes' attributes every time):
>>> class A(Model):
... foo = Integer()
...
>>> class B(A):
... bar = String()
...
>>> B._fields
{'foo': Integer('A.foo'), 'bar': String('B.bar')}
Again, this can be done (without inheritance) with a class decorator:
def mod...