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How to detect if app is being built for device or simulator in Swift
... ...
#endif
After Swift 4.1 version
Latest use, now directly for all in one condition for all types of simulators need to apply only one condition -
#if targetEnvironment(simulator)
// your simulator code
#else
// your real device code
#endif
For more clarification, you can check S...
How can I access “static” class variables within class methods in Python?
...
As with all good examples, you've simplified what you're actually trying to do. This is good, but it is worth noting that python has a lot of flexibility when it comes to class versus instance variables. The same can be said of meth...
Check if PHP session has already started
I have a PHP file that is sometimes called from a page that has started a session and sometimes from a page that doesn't have session started. Therefore when I have session_start() on this script I sometimes get the error message for "session already started". For that I've put these lines:
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Can iterators be reset in Python?
...ary data needs to be
stored). In general, if one iterator
uses most or all of the data before
another iterator starts, it is faster
to use list() instead of tee().
Basically, tee is designed for those situation where two (or more) clones of one iterator, while "getting out of sync" with ea...
Generate random numbers using C++11 random library
... functions and why not to use rand(). In it, he included a slide that basically solves your question. I've copied the code from that slide below.
You can see his full talk here: http://channel9.msdn.com/Events/GoingNative/2013/rand-Considered-Harmful
#include <random>
#include <iostream&g...
Create a CSV File for a user in PHP
...ord2,record3\n";
die;
etc
Edit: Here's a snippet of code I use to optionally encode CSV fields:
function maybeEncodeCSVField($string) {
if(strpos($string, ',') !== false || strpos($string, '"') !== false || strpos($string, "\n") !== false) {
$string = '"' . str_replace('"', '""', $st...
How to automatically remove trailing whitespace in Visual Studio 2008?
Is it possible to configure Visual Studio 2008 to automatically remove whitespace characters at the end of each line when saving a file? There doesn't seem to be a built-in option, so are there any extensions available to do this?
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MongoDB SELECT COUNT GROUP BY
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I need some extra operation based on the result of aggregate function. Finally I've found some solution for aggregate function and the operation based on the result in MongoDB. I've a collection Request with field request, source, status, requestDate.
Single Field Group By & Count:
db.Request...
What really happens in a try { return x; } finally { x = null; } statement?
...L level you can't return from inside an exception-handled block. It essentially stores it in a variable and returns afterwards
i.e. similar to:
int tmp;
try {
tmp = ...
} finally {
...
}
return tmp;
for example (using reflector):
static int Test() {
try {
return SomeNumber();
...
What is the most robust way to force a UIView to redraw?
...ouble with that, you're likely running into one of these issues:
You're calling it before you actually have the data, or your -drawRect: is over-caching something.
You're expecting the view to draw at the moment you call this method. There is intentionally no way to demand "draw right now this ver...