OO API

[brzuchal]

IMO the project has a potential.
Are you going to provide OO API so there won't be a plenty of global space functions to be used?

[brzuchal]

It can be similar to composer ClassLoader

class ClassLoader {
    public function getPrefixes(): array;

    public function addPsr0(string $prefix, string|array $paths, bool $prepend = false): void;
    public function setPsr0(string $prefix, string|array $path, bool $prepend = false): void;
    public function getPsr0Prefixes(): array;

    public function addPsr4(string $prefix, string|array $path, bool $prepend = false): void;
    public function setPsr4(string $prefix, string|array $path, bool $prepend = false): void;
    public function getPsr4Prefixes(): array;

    public function register(bool $prepend = false): void; // registers [$this, 'loadClass']
    public function unregister(): void; // unregisters [$this, 'loadClass']
    public function loadClass(string $class): bool?;

    public function findFile(string $class): string?;
}

[pprkut]

Not anytime soon, no. I intentionally went for functions instead of objects for this extension because I don't see how autoloading warrants the added complexity.
Further, there's not going to be a whole lot of global functions to begin with. Of the 11 example methods you listed, 2 currently exist, 1 of which isn't really meant for users. I could see myself adding functions for getting the registered PSR-4 prefixes and unregistering a PSR-4 prefix and then that's about the functionality this extension needs, IMHO.