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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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MongoDB SELECT COUNT GROUP BY
...
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...
Good examples of Not a Functor/Functor/Applicative/Monad?
...but not Applicative:
I don't have a good example. There is Const, but ideally I'd like a concrete non-Monoid and I can't think of any. All types are basically numeric, enumerations, products, sums, or functions when you get down to it. You can see below pigworker and I disagreeing about whether ...
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...
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...
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...
ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type
...'Modified'. Before changing the state, the state is set to 'Detached' but calling Attach() does throw the same error. I'm using EF6.
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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...
How to obtain a Thread id in Python?
...
Using the logging module you can automatically add the current thread identifier in each log entry.
Just use one of these LogRecord mapping keys in your logger format string:
%(thread)d : Thread ID (if available).
%(threadName)s : Thread name (if available).
a...