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Simple example of threading in C++
Can someone post a simple example of starting two (Object Oriented) threads in C++.
7 Answers
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Creating anonymous objects in php
... some years, but I think I need to keep the information up to date!
Since PHP 7 it has been possible to create anonymous classes, so you're able to do things like this:
<?php
class Foo {}
$child = new class extends Foo {};
var_dump($child instanceof Foo); // true
?>
You can ...
How to use php serialize() and unserialize()
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A PHP array or object or other complex data structure cannot be transported or stored or otherwise used outside of a running PHP script. If you want to persist such a complex data structure beyond a single run of a script, you ...
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 ==! ...
How do I read from parameters.yml in a controller in symfony2?
...er: '%api_user%'
App\:
resource: ..
2. Any Controller
<?php declare(strict_types=1);
final class ApiController extends SymfonyController
{
/**
* @var string
*/
private $apiPass;
/**
* @var string
*/
private $apiUser;
public function __co...
How to convert a std::string to const char* or char*?
...tr.begin(), str.end());
writable.push_back('\0');
// get the char* using &writable[0] or &*writable.begin()
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Is the practice of returning a C++ reference variable evil?
...reference is perfectly normal and happens all the time.
If you mean:
int& getInt() {
int i;
return i; // DON'T DO THIS.
}
That is all sorts of evil. The stack-allocated i will go away and you are referring to nothing. This is also evil:
int& getInt() {
int* i = new int;
...
Python dictionary: Get list of values for list of keys
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found_keys = mapping.keys() & iterable gives TypeError: unsupported operand type(s) for &: 'list' and 'list' on python 2.7; `found_keys = [key for key in mapping.keys() if key in iterable] works best
– NotGaeL
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Is it better in C++ to pass by value or pass by constant reference?
.... Using pass-by-reference the compiler cannot assume that always. Simple example:
foo * f;
void bar(foo g) {
g.i = 10;
f->i = 2;
g.i += 5;
}
the compiler can optimize it into
g.i = 15;
f->i = 2;
since it knows that f and g doesn't share the same location. if g was a referenc...
Is there any difference between __DIR__ and dirname(__FILE__) in PHP?
...7)
But, there are at least two differences :
__DIR__ only exists with PHP >= 5.3
which is why dirname(__FILE__) is more widely used
__DIR__ is evaluated at compile-time, while dirname(__FILE__) means a function-call and is evaluated at execution-time
so, __DIR__ is (or, should be) faste...