gistfile1.php

<?php

$dispatcher = new Ai1ec_Event_Dispatcher();

$callback_filter = new Ai1ec_Event_Callback_Filter( $this->_registry, 'model.settings', 'modify2' );
$dispatcher->register( 'title', $callback_filter, 19, 2 );

$callback_filter2 = new Ai1ec_Event_Callback_Filter( $this->_registry, 'model.settings', 'modify' );
$dispatcher->register( 'title', $callback_filter2, 17, 2 );

$callback_filter3 = new Ai1ec_Event_Callback_Filter( $this->_registry, 'model.settings', 'modify' );
$dispatcher->register( 'title', $callback_filter3, 22, 2 );

echo 'Result: ' . apply_filters( 'title', 'Long Name', 23 );
// Result: Long Name (23) [23] (23)

echo 'Result: ' . apply_filters( 'title', 'Other Name', 2 );

echo 'Result: ' . apply_filters( 'title', 'Justas is bad', 8 );

echo 'Result: ' . apply_filters( 'title', 'But not very much', 123 );