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Not class selector in jQuery
... It is quicker now that the vast majority of browsers support querySelectorAll, but that hasn't always been the case.
– lonesomeday
Jul 23 '13 at 8:18
4
...
What is the difference between null and undefined in JavaScript?
...he typeof operator returns 'object' for a value that is null. This was actually an error in the original JavaScript implementation that was then copied in ECMAScript. Today, it is rationalized that null is considered a placeholder for an object, even though, technically, it is a primitive value."
...
How do you properly use namespaces in C++?
...
Namespaces are packages essentially. They can be used like this:
namespace MyNamespace
{
class MyClass
{
};
}
Then in code:
MyNamespace::MyClass* pClass = new MyNamespace::MyClass();
Or, if you want to always use a specific namespace, you can d...
How to make connection to Postgres via Node.js
I find myself trying to create a postgres database, so I installed postgres and started a server with initdb /usr/local/pgsql/data , then I started that instance with postgres -D /usr/local/pgsql/data now how can I interact with this through node? For example, what would the connectionstring be...
Using Case/Switch and GetType to determine the object [duplicate]
...
If I really had to switch on type of object, I'd use .ToString(). However, I would avoid it at all costs: IDictionary<Type, int> will do much better, visitor might be an overkill but otherwise it is still a perfectly fine solu...
Why does one hot encoding improve machine learning performance?
...e. The three possible values of w×x are 0, w and 2×w. Either these three all lead to the same decision (they're all < b or ≥b) or "UK" and "French" lead to the same decision, or "French" and "US" give the same decision. There's no possibility for the model to learn that "UK" and "US" should b...
Which is faster: Stack allocation or Heap allocation
...
Stack allocation is much faster since all it really does is move the stack pointer.
Using memory pools, you can get comparable performance out of heap allocation, but that comes with a slight added complexity and its own headaches...
What's the easiest way to install a missing Perl module?
...
On Unix:
usually you start cpan in your shell:
# cpan
and type
install Chocolate::Belgian
or in short form:
cpan Chocolate::Belgian
On Windows:
If you're using ActivePerl on Windows, the PPM (Perl Package Manager) has much of t...
C# - Selectively suppress custom Obsolete warnings
...le:
using System;
class Test
{
[Obsolete("Message")]
static void Foo(string x)
{
}
static void Main(string[] args)
{
#pragma warning disable 0618
// This one is okay
Foo("Good");
#pragma warning restore 0618
// This call is bad
Foo("Bad");
...
Compare if two variables reference the same object in python
...check which unique object each variable name refers to.
In [1]: x1, x2 = 'foo', 'foo'
In [2]: x1 == x2
Out[2]: True
In [3]: id(x1), id(x2)
Out[3]: (4509849040, 4509849040)
In [4]: x2 = 'foobar'[0:3]
In [5]: x2
Out[5]: 'foo'
In [6]: x1 == x2
Out[6]: True
In [7]: x1 is x2
Out[7]: False
In [8]:...