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The tilde operator in Python
...a unary operator (taking a single argument) that is borrowed from C, where all data types are just different ways of interpreting bytes. It is the "invert" or "complement" operation, in which all the bits of the input data are reversed.
In Python, for integers, the bits of the twos-complement repr...
How do I unset an element in an array in javascript?
...ipt Arrays are not associative arrays like those you might be used to from PHP. If your "array key" is a string, you're no longer operating on the contents of an array. Your array is an object, and you're using bracket notation to access the member named <key name>. Thus:
var myArray = [];
m...
Why do people use __(double underscore) so much in C++
...specific, and are slightly more detailed than some others have suggested.
All identifiers that contain a double underscore or start with an underscore followed by an uppercase letter are reserved for the use of the implementation at all scopes, i.e. they might be used for macros.
In addition, all ...
C#: Printing all properties of an object [duplicate]
Is there a method built in to .NET that can write all the properties and such of an object to the console? Could make one using reflection of course, but I'm curious to if this already exists... especially since you can do it in Visual Studio in the Immediate Window. There you can an object name (wh...
What is the id( ) function used for?
... Python objects.
Is it the same with memory addresses in C?
Conceptually, yes, in that they are both guaranteed to be unique in their universe during their lifetime. And in one particular implementation of Python, it actually is the memory address of the corresponding C object.
If yes, wh...
Declaring variables inside or outside of a loop
...
The scope of local variables should always be the smallest possible.
In your example I presume str is not used outside of the while loop, otherwise you would not be asking the question, because declaring it inside the while loop would not be an option, since it would not comp...
How do exceptions work (behind the scenes) in c++
...
Instead of guessing, I decided to actually look at the generated code with a small piece of C++ code and a somewhat old Linux install.
class MyException
{
public:
MyException() { }
~MyException() { }
};
void my_throwing_function(bool throwit)
{
if (...
MongoDB: Is it possible to make a case-insensitive query?
...
This works perfectly. Got it working in PHP with: $collection->find(array('key' => new MongoRegex('/'.$val.'/i')));
– Luke Dennis
Dec 9 '09 at 4:22
...
String concatenation in Ruby
...ficient in term of memory/speed from what I've seen (not measured though). All three methods will throw an uninitialized constant error when ROOT_DIR is nil.
When dealing with pathnames, you may want to use File.join to avoid messing up with pathname separator.
In the end, it is a matter of taste....
HTTP GET Request in Node.js Express
...rks on Node will serve you well if you need to use an HTTP client on Ruby, PHP, Java, Python, Objective C, .Net or Windows 8 as well. As far as I can tell the unirest libraries are mostly backed by existing HTTP clients (e.g. on Java, the Apache HTTP client, on Node, Mikeal's Request libary) - Unir...