Chemaclass

<?php
function gen()
{
    yield 1;
    yield 2;
    yield from gen2();
}

function gen2() 
{

Chemaclass

<?php
$gen = (function() {
    yield 1;
    yield 2;
    return 3;
})();

foreach ($gen as $val) {
    echo $val, ' ';
}

Chemaclass

<?php
// Pre PHP 7 code
use some\namespace\ClassA;
use some\namespace\ClassB;
use some\namespace\ClassC as C;

use function some\namespace\fn_a;
use function some\namespace\fn_b;
use function some\namespace\fn_c;

Chemaclass

<?php
class A {
  private $x = "1";
}

// Pre PHP 7 code
$getX = function() {return $this->x;};
$getXCB = $getX->bindTo(new A, 'A'); // intermediate closure
echo $getXCB();                      // outputs "1"

Chemaclass

<?php
echo "\u{aa}";     // ª
echo "\u{0000aa}"; // ª (the same but with optional leading 0's)
echo "\u{9999}";   // 香

Chemaclass

<?php
interface Logger {
    public function log(string $msg);
}

class Application {
    private $logger;

    public function getLogger(): Logger {
         return $this->logger;

Chemaclass

<?php
define('ANIMALS', [
    'dog',
    'cat',
    'bird'
]);

echo ANIMALS[1]; // outputs "cat"

Chemaclass

<?php
// Integers
echo 1 <=> 1; // 0
echo 1 <=> 2; // -1
echo 2 <=> 1; // 1

// Floats
echo 1.5 <=> 1.5; // 0
echo 1.5 <=> 2.5; // -1
echo 2.5 <=> 1.5; // 1

Chemaclass

<?php
// Fetches the value of $_GET['user'] and returns 'nobody'
// if it does not exist.
$username = $_GET['user'] ?? 'nobody';
// This is equivalent to:
$username = isset($_GET['user']) ? $_GET['user'] : 'nobody';

// Coalescing can be chained: this will return the first
// defined value out of $_GET['user'], $_POST['user'], and
// 'nobody'.

Chemaclass

<?php
function arraysSum(array ...$arrays): array
{
    return array_map(function(array $array): int {
        return array_sum($array);
    }, $arrays);
}

print_r(arraysSum([1,2,3], [4,5,6], [7,8,9]));
?>