Magic getters/setters in PHP … Any comments/suggestions?

Question

So, I'm playing around with PHP, trying to write a small ORM. Having worked with Magento quite a bit lately, I've fallen in love with the automagic getters/setters that Magento, I think, inherited from Zend.

For those, who've never seen it in action, this is what I'm talking about:

$my_object->setSomeProperty('foo');

just works, as does

$my_object->getSomeProperty();

which obviously yields "foo".

Since I'm trying to implement an ORM, my goal is to provide the user with the ability to use generic functions on one hand, where

$orm_object->setSomeProperty('foo')

would map to

$orm_object->set('some_property', 'foo') // set() would obviously be a generic part of the ORM

by convention. On the other hand, if the user wanted to handle some situations differently, he could do so by defining a more specifically named function.

class foo extends ORM {
    function setSome($arg_1, $arg_2)
    {
        …
    }
}

The above example call

$orm_object->setSomeProperty('foo')

would now be mapped to

$orm_object->setSome('property', 'foo')

instead of the default set().

Alright, let's get to the point: Do you have any feedback on my implementation?

function __call($name, $arguments) {
    if(preg_match('/([a-z]+)/', $name, $matches))
    {
        $action = $matches[0];
        if(preg_match_all('/([A-Z]+)([^A-Z]+)/', $name, $matches))
        {
            $matches = $matches[0];
            array_unshift(&$matches, $action);
            for ($i = count($matches); $i > 0; $i--)
            {
                $potential_func_name = implode('', array_slice($matches, 0, $i));
                if (method_exists($this, $potential_func_name))
                {
                    $arguments_rest = array_slice($matches, $i);
                    break; // found matching function! 
                }
            }

            // handle number of arguments now!
            $reflector = new ReflectionClass($this);
            $num_expected_params = count($reflector->getMethod($potential_func_name)->getParameters());

            $num_expected_params = $num_expected_params - count($arguments);

            $params = array();
            for ($i = $num_expected_params; $i > 1; $i--)
            {
                $params[] = strtolower(array_shift($arguments_rest));
            }

            $last_var = '';
            $i = 0;
            foreach($arguments_rest as $part)
            {
                $last_var .= strtolower($part);
                $i++;
                if ($i != count($arguments_rest)) $last_var .= '_';
            }

            $params[] = $last_var;

            if (count($arguments) == 1) {
                $arguments = array_shift(&$arguments);
            }

            $params[] = $arguments;

            return(call_user_func_array(array($this, $potential_func_name), $params));
        }
    }
}

Answer 1

This is how I would probably implement task similar to yours:

class A {
    public function set($property, $value)
    {
        echo sprintf('setting %s = %s', 
            $property, $value)."\n";
    }

    public function setFirstName($value)
    {
        $this->set('first_name', $value);
    }

    public function __call($name, $arguments)
    {
        if (!preg_match('/^(get|set)(.+?)$/i', $name, $matches)) {
            throw new BadMethodCallException(sprintf('method `%s` doesn\'t exits', $name));
        }

        list(, $method, $property) = $matches;

        $property = preg_replace('/([a-z\d])([A-Z])/', '\\1_\\2', $property);
        $method   = strtolower($method);

        if ('set' == $method) {
            array_unshift($arguments, strtolower($property));
        }

        return call_user_func_array(array($this, $method), $arguments);
    }
}

$a = new A();
$a->setFirstName('John');
$a->setLastName('McLane');

Output:

setting first_name = John

setting last_name = McLane