Transformations

If the transformation is occurring as you pull data out of the subject, then it is probably less verbose to simply use the fourth parameter of the get() method, the value callback. If, however, you want to transform the value inside of $subject, then this page will advise on how to do that.

Transform with a function name

The function must only take a single parameter, which is the $value. To use a function with a different signature, wrap it in an anonymous function.

This example will transform a value via strtoupper(), observe:

$subject = array('name' => 'bob');
$obj->getThen($subject, 'name')->call('strtoupper')->set($subject);

// $subject['name'] === 'BOB';

This example will assign it to a different key:

$subject = array('name' => 'bob');
$obj->getThen($subject, 'name')->call('strtoupper')->set($subject, 'ucname');

// $subject['name'] === 'bob';
// $subject['ucname'] === 'BOB';

Transform with an anonymous function

$from = array('being' => 'dog');
$obj->getThen($from, 'being')
    ->call(function ($value) {
        $value = str_split($value);
        $value = array_reverse($value);

        return implode($value);
    })
    ->set($from);

// $from['being'] === 'god';