Loading Classes Automatically in PHP (code to accompany https://youtu.be/93pCiZT99Ks)

composer.json

{
    "autoload": {
        "psr-4": {
            "": "src/"
        }
    }
}

index.php

<?php

use Framework\Router;

/*
spl_autoload_register(function(string $class) {

    $path = 'src/' . str_replace('\\', '/', $class) . '.php';

    require $path;

});
*/

require 'vendor/autoload.php';

$user = new App\User;

echo $user->getName();

$product = new Database\Models\ProductModel;

echo $product->getId();

$router = new Router;

echo get_class($router);

$order = new Database\Models\OrderModel;

echo get_class($order);