the difference between -state and state

[ryuuyq]

below，there is 'from' => '-proposed' and 'from' => 'proposed'.

what is the difference ?

    'callbacks' => array(
        'before' => array(
            array(
                'from' => '-proposed',
                'do' => function(Finite\StatefulInterface $document, \Finite\Event\TransitionEvent $e) {
                    echo 'Applying transition '.$e->getTransition()->getName(), "\n";
                }
            ),
            array(
                'from' => 'proposed',
                'do' => function() {
                    echo 'Applying transition from proposed state', "\n";
                }
            )
        ),
        'after' => array(
            array(
                'to' => array('accepted'), 'do' => array($document, 'display')
            )
        )
    )

[imzeali]

[tsmgeek]

Just need some more clarification.

It will apply to all states except that one mentioned?
If so how do you add multiple exclusions?