private function isValidCallback($callback)
    {
        // For security purposes, we don't want to call anything that isn't
        // an object callback
        if (is_string($callback)) {
            return false;
        }

        if (is_array($callback)) {
            $target = array_shift($callback);
            if (! is_object($target)) {
                return false;
            }
        }

        // Object callback -- always okay
        return true;
    }
private function isValidCallback($callback)
    {
        // For security purposes, we don't want to call anything that isn't
        // an object callback
        if (is_string($callback)) {
            return false;
        }

        if (is_array($callback)) {
            $target = array_shift($callback);
            if (! is_object($target)) {
                return false;
            }
        }

        // Object callback -- always okay
        return true;
    }
private function isValidCallback ( $ callback ) { // For security purposes, we don't want to call anything that isn't // an object callback if ( is_string ( $ callback ) ) { return false ; } if ( is_array ( $ callback ) ) { $ target = array_shift ( $ callback ) ; if ( ! is_object ( $ target ) ) { return false ; } } // Object callback -- always okay return true ; }
Is the callback provided valid?

@param  callback $callback
@return bool
Is the callback provided valid?