flight/core/Dispatcher.php
public static function execute($callback, array &$params = array()) {
        if (is_callable($callback)) {
            return is_array($callback) ?
                self::invokeMethod($callback, $params) :
                self::callFunction($callback, $params);
        }
        else {
            throw new \Exception('Invalid callback specified.');
        }
    }
public static function execute($callback, array &$params = array()) {
        if (is_callable($callback)) {
            return is_array($callback) ?
                self::invokeMethod($callback, $params) :
                self::callFunction($callback, $params);
        }
        else {
            throw new \Exception('Invalid callback specified.');
        }
    }
Executes a callback function.

@param callback $callback Callback function
@param array $params Function parameters
@return mixed Function results
@throws \Exception