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Naming convention - underscore in C++ and C# variables
It's common to see a _var variable name in a class field. What does the underscore mean? Is there a reference for all these special naming conventions?
...
How do you add a Dictionary of items into another Dictionary
...
@animal_chin Because we have to implement half of the language ourselves? Yes. Impressed. Don't get me wrong I love operator overloading. I just don't love having to use it for basic features that should be built in.
...
Creating the Singleton design pattern in PHP5
...ctor so nobody else can instantiate it
*
*/
private function __construct()
{
}
}
To use:
$fact = UserFactory::Instance();
$fact2 = UserFactory::Instance();
$fact == $fact2;
But:
$fact = new UserFactory()
Throws an error.
See http://php.net/manual/en/language.variable...
Is there a way for multiple processes to share a listening socket?
...rt socket
import os
def main():
serversocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
serversocket.bind(("127.0.0.1", 8888))
serversocket.listen(0)
# Child Process
if os.fork() == 0:
accept_conn("child", serversocket)
accept_conn("parent", serversocket)
...
What is the best way to ensure only one instance of a Bash script is running? [duplicate]
...e
### HEADER ###
LOCKFILE="/var/lock/`basename $0`"
LOCKFD=99
# PRIVATE
_lock() { flock -$1 $LOCKFD; }
_no_more_locking() { _lock u; _lock xn && rm -f $LOCKFILE; }
_prepare_locking() { eval "exec $LOCKFD>\"$LOCKFILE\""; trap _no_more_locking EXIT; }
# ON START
_prepare_l...
Python: Why is functools.partial necessary?
...mbda:
>>> pickle.dumps(partial(int))
'cfunctools\npartial\np0\n(c__builtin__\nint\np1\ntp2\nRp3\n(g1\n(tNNtp4\nb.'
>>> pickle.dumps(lambda x: int(x))
Traceback (most recent call last):
File "<ipython-input-11-e32d5a050739>", line 1, in <module>
pickle.dumps(lambd...
What is the difference between “px”, “dip”, “dp” and “sp”?
...
@android_developer (5 comments above) dp does not have the exact same physical length. (Although it is close.) See @Fraggle's comment about bucketing. What this means is that 48dp will be roughly 8mm (0.3 inch), but it may vary up to...
How to [recursively] Zip a directory in PHP?
...ion to be loaded.
function Zip($source, $destination)
{
if (!extension_loaded('zip') || !file_exists($source)) {
return false;
}
$zip = new ZipArchive();
if (!$zip->open($destination, ZIPARCHIVE::CREATE)) {
return false;
}
$source = str_replace('\\', '/'...
What's the best UI for entering date of birth? [closed]
...birthdate.
A text box with an example is clear, quick and easy to enter:
_______
|_______| (example: 31/3/1970)
This should support flexible formatting such as 1/1/1970 or 20/07/70.
If you have to support different cultures with different date conventions (e.g. US and UK) then this could be err...
What is the difference between Python's list methods append and extend?
...ppend
The list.append method appends an object to the end of the list.
my_list.append(object)
Whatever the object is, whether a number, a string, another list, or something else, it gets added onto the end of my_list as a single entry on the list.
>>> my_list
['foo', 'bar']
>>&...