PHP函数的DI框架

class Container {
    protected $dependencies = [];
    
    public function add_function($name, $fn) {
        $this->dependencies[$name] = $fn;
    }
    
    public function add_dependency($name, $dependency) {
        $this->dependencies[$name]['dependencies'][] = $dependency;
    }
    
    public function get($name) {
        if(isset($this->dependencies[$name]['dependencies'])) {
            $dependencies = [];
            foreach($this->dependencies[$name]['dependencies'] as $dependency) {
                $dependencies[] = $this->get($dependency);
            }
            return call_user_func_array($this->dependencies[$name], $dependencies);
        }
        return $this->dependencies[$name];
    }
}

$container = new Container();

$container->add_function('handler', function($request, $db) {
    ...
});

$container->add_dependency('handler', 'request');
$container->add_dependency('handler', 'db');

$handler = $container->get('handler');
$handler($request, $db);