protected function registerCommand($alias, $class)
    {
        $this
            ->define($alias, function($channel, $receiver) use($class) {
                return new $class($channel, $receiver);
            })
            ->define($class, function($channel, $receiver) use($class) {
                return new $class($channel, $receiver);
            })
        ;
    }
protected function registerCommand($alias, $class)
    {
        $this
            ->define($alias, function($channel, $receiver) use($class) {
                return new $class($channel, $receiver);
            })
            ->define($class, function($channel, $receiver) use($class) {
                return new $class($channel, $receiver);
            })
        ;
    }
protected function registerCommand ( $ alias , $ class ) { $ this -> define ( $ alias , function ( $ channel , $ receiver ) use ( $ class ) { return new $ class ( $ channel , $ receiver ) ; } ) -> define ( $ class , function ( $ channel , $ receiver ) use ( $ class ) { return new $ class ( $ channel , $ receiver ) ; } ) ; }
Register command under class and alias.

@param string $alias
@param string $class
Register command under class and alias .