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Difference between “!==” and “==!” [closed]
Yesterday I stumbled over this when I modified PHP code written by someone else. I was baffled that a simple comparison ( if ($var ==! " ") ) didn't work as expected. After some testing I realized that whoever wrote that code used ==! instead of !== as comparison operator. I've never seen ==! ...
Immutable array in Java
.... Since even an empty array takes up some memory, you can save that memory allocation by creating a constant empty array, and always passing it to the toArray method. That method will allocate a new array if the array you pass doesn't have enough space, but if it does (the list is empty), it will re...
How do I use extern to share variables between source files?
...ler is informed that a
variable exists (and this is its type); it does not allocate the
storage for the variable at that point.
A variable is defined when the compiler allocates the storage for
the variable.
You may declare a variable multiple times (though once is sufficient);
you may only defin...
Cannot pass null argument when using type hinting
...
PHP 7.1 or newer (released 2nd December 2016)
You can explicitly declare a variable to be null with this syntax
function foo(?Type $t) {
}
this will result in
$this->foo(new Type()); // ok
$this->foo(null); // ok
$...
When and why I should use session_regenerate_id()?
Why and when should I use the session_regenerate_id() function in php?
Should I always use it after I use the session_start() ?
I've read that I have to use it to prevent session fixation, is this the only reason?
...
On delete cascade with doctrine2
..., you configure the @JoinColumn with
the onDelete="CASCADE" option.
<?php
namespace Entities;
use Doctrine\Common\Collections\ArrayCollection;
/**
* @Entity
* @Table(name="contacts")
*/
class Contact
{
/**
* @Id
* @Column(type="integer", name="contact_id")
* @Gener...
How to compare two NSDates: Which is more recent?
...
NSDate *retVal;
NSDateComponents *components = [[NSDateComponents alloc] init];
[components setDay:days];
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
retVal = [gregorian dateByAddingComponents:components toDate:self options:0];
...
Why shouldn't I use “Hungarian Notation”?
... but that would incur a huge overhead for dynamic languages (Python, Ruby, PHP or Javascript).
– too much php
Dec 29 '08 at 3:45
22
...
How to listen for changes to a MongoDB collection?
...time, or is there a way my script can wait for inserts to occur? This is a PHP project that I am working on, but feel free to answer in Ruby or language agnostic.
...
How many concurrent AJAX (XmlHttpRequest) requests are allowed in popular browsers?
...njoy it!!!
Just because I have had problems with my hosting provider
<?php /*
Author: Luis Siquot
Purpose: Check ajax performance and errors
License: GPL
site5: Please don't drop json requests (nor delay)!!!!
*/
$r = (int)$_GET['r'];
$w = (int)$_GET['w'];
if($r) {
sleep($w);
ech...