Do I need to spread class loaders into different classes to maintain the Single Responsibility Principle?

Question

PHP

There is actually a class that configures the application (core.php). It sets encodings and declares global helper CONSTANTS. Is it possible to write autoload functions into it, or is it better to put them in separate classes? (spl_autoload)

Answer 1

Have you just been thrashed? In the yard 2016))
The Internet is full of articles "why global variables are evil."
PSR-4 + composer. Autoloading is a problem solved a long time ago, you should not invent an unnecessary bicycle for anyone (including you).

Answer 2

and declares global auxiliary variables.

about autoloading you have already been answered - use composer. And at the expense of global "auxiliary" variables - get rid of them. Use a dependency container or service locator to manage dependencies and system configuration.
Either learn how to make an isolated state - or just forget it and write procedurally like in the days of php4. There is nothing wrong with that, the vast majority do not even know that they have proceduralism with classes.