Domain-Driven Design in PHP

PSR-0 and PSR-4 Namespacing

Namespaces entered the scene when PHP 5.3 was introduced, along with other important features. This was a major shift, and a group of the most important framework collaborators emerged with PHP-FIG, an acronym of PHP Framework Interop Group, in an attempt to standardize and unify common aspects of the framework and library creation. The first PHP Standard Recommendation (PSR) the group released was an autoloading standard that, in short, proposed a one-to-one relation between a class and a PHP file using namespaces. Today, PSR-4 — a simplification of PSR-0 that still maintains the relation between classes and physical PHP files — is the preferred and recommended way to structure code. We believe that this should ...