protected $listen = [  
    'Illuminate\Database\Events\QueryExecuted' => [
        'App\Listeners\QueryListener',
    ],
];

namespace App\Providers;
use Illuminate\Contracts\Events\Dispatcher as DispatcherContract;
use Illuminate\Foundation\Support\Providers\EventServiceProvider as ServiceProvider;
class EventServiceProvider extends ServiceProvider
{
    /**
     * The event listener mappings for the application.
     *
     * @var array
     */
    protected $listen = [
        'App\Events\SomeEvent' => [
            'App\Listeners\EventListener',
        ],
        'Illuminate\Database\Events\QueryExecuted' => [
            'App\Listeners\QueryListener',
        ],
    ];
    /**
     * Register any other events for your application.
     *
     * @param  \Illuminate\Contracts\Events\Dispatcher  $events
     * @return void
     */
    public function boot(DispatcherContract $events)
    {
        parent::boot($events);
        //
    }
}

$sql = str_replace("?", "'%s'", $event->sql);
$log = vsprintf($sql, $event->bindings);
Log::info($log);

namespace App\Listeners;
use Log;
use Illuminate\Database\Events\QueryExecuted;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Contracts\Queue\ShouldQueue;
class QueryListener
{
    /**
     * Create the event listener.
     *
     * @return void
     */
    public function __construct()
    {
        //
    }
    /**
     * Handle the event.
     *
     * @param  QueryExecuted  $event
     * @return void
     */
    public function handle(QueryExecuted $event)
    {
        $sql = str_replace("?", "'%s'", $event->sql);
        $log = vsprintf($sql, $event->bindings);
        Log::info($log);
    }
}

class Student
{
    public function __construct()
    {
        $this->name = 'durban';
    }
}

$student = new Student();

function enroll(Student $student, array $classes)
{
    foreach ($classes as $class) {
        echo "Enrolling " . $student->name . " in " . $class . "\n";
    }
}

// enroll("name", ["class 1", "class 2"]);// Fatal error: Uncaught TypeError: Argument 1 passed to enroll() must be an instance of Student, string given
// enroll($student, "class"); // Fatal error: Uncaught TypeError: Argument 2 passed to enroll() must be of the type array, string given
enroll($student, array("class 1", "class 2"));

function stringTest(string $string)
{
    echo $string . "\n";
}
stringTest("a string");

declare (strict_types = 1);

function getTotal(float $a, float $b)
{
    return $a + $b;
}
// getTotal('a', 2); //Argument 1 passed to getTotal() must be of the type float, string given,
$total = getTotal(3, 2);
echo $total . "\n";

function getSum(float $a, float $b): int
{
    // return $a + $b; // Fatal error: Uncaught TypeError: Return value of getTotal() must be of the type integer, float returned
    return (int) ($a + $b); // truncate float like non-strict
}
$sum = getSum(3, 6);
echo $sum . "\n";

try {
    // Code that may throw an Exception or Error.
} catch (Throwable $t) {
    // Executed only in PHP 7, will not match in PHP 5
} catch (Exception $e) {
    // Executed only in PHP 5, will not be reached in PHP 7
}

$name = $firstName ??  "Guest";

$name = $firstName ?? $username ?? $placeholder ?? “Guest”;

$compare = 2 <=> 1

2 < 1? return -1
2 = 1? return 0
2 > 1? return 1

$int = random_int(1, 2);
var_dump($int);

$bytes = random_bytes(5);
var_dump(bin2hex($bytes));

$models = static::where('user_id', $userId)->leftJoin('product_gift', function ($join) {
    $join->on('product_gift_exchange_order.prd_id', '=', 'product_gift.prd_id');
    $join->on('product_gift_exchange_order.gift_code', '=', 'product_gift.gift_code');
})->orderBy('product_gift_exchange_order.autokid', 'DESC')->get([
    'product_gift_exchange_order.autokid',
    'product_gift_exchange_order.ctime',
    'product_gift_exchange_order.exchange_amount',
    'product_gift.gift_name',
]);