Kraken\Promise\Partial\PromiseTrait::doCancel PHP Method

    public static function doCancel($promiseOrValue = null)
    {
        if (!$promiseOrValue instanceof PromiseInterface) {
            return new PromiseCancelled($promiseOrValue);
        }
        return self::doResolve($promiseOrValue)->then(function ($value) {
            return new PromiseCancelled($value);
        }, function ($value) {
            return new PromiseCancelled($value);
        });
    }