Throughout the StyleGuide, the term "class" refers to classes, interfaces, traits and other similar structures.
Apart from one exception, the Composer autoloader, there should never be any use of require
or include
statements. Every class within the system should be addressable using autoloaders, using the PSR-4 Autoloader standard where possible.
If PSR-4 is not adhered to for some reason, such as utilising Path Mapping class names that reference URLs to class names, there should be a formal alternative autoloader that has well defined, documented and predictable behaviour.