Re: pipes, scalar objects and on?

On Tue, Jul 18, 2023 at 3:18 PM Olle Härstedt <olleharstedt@gmail.com> wrote: > > 2023-07-18 14:48 GMT+02:00, someniatko <someniatko@gmail.com>: > > I am glad this topic arose! I was also planning to write on this topic to > > the internals mailing list, but have abandoned this idea, because I feel it > > might be inconvenient for the real active PHP developers on the list to > > receive too many emails from the people which don't actively participate in > > the development itself. > > > > My interest in the pipe operator might seem a little non-standard - > > basically what I'd really want to see is a **nullable** pipe operator! > > > > There is a popular library github.com/schmittjoh/php-option, which has 250 > > MILLION installations. Basically what it provides is a class-wrapper of a > > value of lack thereof: it's either Some<Type> > > or None. I also maintain > > a similar library > > https://packagist.org/packages/someniatko/result-type > > which fixes some shortcomings of the original one related to the static > > analysis, but this is another story. Basically what the stats tell us is > > that such stuff is popular among the PHP community. > > > > In my eyes, it is actually semantically equivalent to the nullable PHP > > types: ?Type. And some operations provided by the lib, are > > actually > > covered by PHP itself, which has multiple null-friendly operators: > > $option->getOrElse($defaultVal) --> > > $nullable ?? $defaultVal > > $option->isEmpty() --> $nullable === > > null > > $option->getOrThrow(new \Exception('blah')) > > --> `$nullable ?? throw new > > \Exception('blah')` > > > > I'd like to use the arguably "more idiomatic" native PHP nullables, rather > > than a foreign-feeling userspace construct, if they were more convenient. > > > > But there is a very important operation, map(), which is > > unfortunately > > not covered by the native PHP, which is Option::map(), and > > here is a > > real-world example: > > ``` > > return $repository->getById($idFromHttpRequest) > > ->map($serializer->serializeToJson(...)) // only executes when the > > Option is Some, not None > > ->map(fn (string $json) => new Response(status: 200, content: $json)) > > ->getOrElse(new Response(status: 404)); > > ``` > > Ehm, wouldn't that be the same as a Pipe class that's configured to > stop on null? > > public function getThing($id) { > return new Pipe( > $this->getData(...), > $this->serializeData(...), > $this->mapToResponse(...) > ) > ->stopOnEmpty() > ->from($id) > ->run(); > } > > Wait, are you using map() for arrays or not? Looks like not. > > Olle > > -- > PHP Internals - PHP Runtime Development Mailing List > To unsubscribe, visit: https://www.php.net/unsub.php > I might be venting, but, I wish the operators RFC had passed...