spl_autoload_register tries to load a class with dependicies

Question

How smart is spl_autoload_register? Does it know to "look ahead" for the class definition in other files before trying to include?

When I run my index.php page I'm seeing Fatal error: Class 'input\input' not found in /var/www/php/classes/input/date.php on line 4

index.php runs the following (after this block it creates an object from one of the classes, if I uncomment the one line everything works perfectly)

function my_autoloader() {
    //include_once "/var/www/php/classes/input/input.php"; //if this is uncommented, it fixes the problem, but I'm not sure why
    foreach (glob("/var/www/php/classes/*/*.php") as $filename)
    {
        require_once $filename;
    }
}
spl_autoload_register('my_autoloader');

is my syntax wrong? is spl_autoload_register supposed to function this way? many other files in these folders depend on eachother and the autoloader seems to "figure it out". I'm not sure why it is suddenly hung up on the "input" class in particular

Answer 1

You're using the autoloader in a wrong way. It is only supposed to load the classes you need for a specific request, not the whole folder.

Read more about autoloading classes properly with some good examples: https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-0.md

Answer 2

You are using it wrongly.
The autoload is used for autoloading only the given class name on the 1st argument of callback, not for loading all classes like you're doing.

For example:

spl_autoload_register(function ($class) {
 // ...
 $class = stream_resolve_include_path(sprintf("%s.php", $class));
 if ($class !== false) {
  require $class
 }
});

$class will contains the class to load it, so, you can use it to find the file containing this class at your filesystem.