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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
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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?
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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
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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...
#define macro for debug printing in C?
.... } while (0) idiom ensures that the code acts like a statement (function call). The unconditional use of the code ensures that the compiler always checks that your debug code is valid — but the optimizer will remove the code when DEBUG is 0.
If you want to work with #ifdef DEBUG, then change th...
What's the difference between a proxy server and a reverse proxy server? [closed]
...ccurate, but perhaps too terse.
I will try to add some examples.
First of all, the word "proxy" describes someone or something acting on behalf of someone else.
In the computer realm, we are talking about one server acting on the behalf of another computer.
For the purposes of accessibility, I wi...
How to create GUID / UUID?
I'm trying to create globally-unique identifiers in JavaScript. I'm not sure what routines are available on all browsers, how "random" and seeded the built-in random number generator is, etc.
...
What is unit testing and how do you do it? [duplicate]
...r program into pieces, and subjecting each piece to a series of tests.
Usually tests are run as separate programs, but the method of testing varies, depending on the language, and type of software (GUI, command-line, library).
Most languages have unit testing frameworks, you should look into one ...