In the old days of PHP, if you wanted to bring a third-party library into your PHP project, or bring in your functions and classes from separate PHP files, you would use include or require statements. With the arrival of PHP autoloading, you would use the __autoload magic method (which is now deprecated since PHP 7.2) or spl_autoload to automatically call your code. Then came true namespace support in PHP 5.3, where developers and frameworks can devise their approaches to prevent naming collisions. But still, it was quite far from ideal because of the battle between different approaches. You can imagine a situation where you have two frameworks – framework A and framework B – and individual developers disagreeing with each other and implementing their own ways to achieve the same result. This was madness.
Today, we comply with PSR-4 (which is the successor of PSR-0) to standardize the autoloading approach and bind developers...
