pon., 1 lip 2024 o 03:01 Larry Garfield <la...@garfieldtech.com> napisał(a):
> On Sun, Jun 30, 2024, at 11:13 AM, Michał Marcin Brzuchalski wrote: > > Hi Richard, > > > > czw., 27 cze 2024, 22:33 użytkownik Richard Miles > > <richard@miles.systems> napisał: > >> > >> > I worked with Joe Watkins to do a proof-of-concept for generic traits. > >> > It's a bit old since it's from 2017, but could be a useful starting > >> > point if you are serious about pursuing this idea: > >> > > >> > > https://github.com/php/php-src/compare/master...morrisonlevi:php-src:parameterized_traits > >> > >> > >> I’m also interested in this; it will help see branches like these. > >> Did you ever get the POC working? What did you feel like was the > biggest hurdle? > > > > There even was an RFC in voting which Joe implemented and it addresses > > nearly what is discussed it this thread https://wiki.php.net/rfc/arrayof > > > > I must admit that the collection<Dict> proposal is bit too complex to > > address such tiny but powerfully in my opinion functionality which is > > typed array. What Derick showed looks more like generic collection and > > such require declaring it's type. In my opinion this is way too mush > > hassle to declare as many collection types as many usages in > > application. Also two collection types with the same collection item > > type will not be compatible from type perspective. While typed array > > seems much more clear and compatible in all places where typed array is > > needed without declaring separate type for each usage. > > > > If I were to choose between typed-array and collection like Derick > > showed a little bit I'd choose typed arrays definitely as a first > > feature to be merged into PHP. > > > > Cheers, > > Michał Marcin Brzuchalski > > Contextual point: Nearly every other major language at this point that has > a meaningful standard library has gone with a three-separate-object > approach (Seq, Set, Dict, called various things). At least Python, > Javascript, Rust, Kotlin, and Swift, in my research. (Go doesn't, but Go > avoids having features by design.) And AFAIK *every* language except PHP > and Lua separates sequences from dictionaries. Typed arrays will not full > resolve the seq vs dict problem, which is arguably PHP's original sin. And > there's a lot of weird issues to resolve around what the syntax could even > be, since PHP has untyped variables. > > The custom collection syntax Derick has been working on is a second-best > alternative to generics, essentially. It is less ergonomic, no question, > but can also be implemented without generics, and so is about 5x easier to > do. If we could get native generics, then I think everyone involved agrees > building collections off of that -- in essentially the same way as every > language I mentioned above --- would be preferable to a custom one-off > syntax. > > --Larry Garfield > Considering other languages it is worth mentioning that Java and C# have generics AND typed arrays that act as a typed list/seq so sure it doesn't solve all problems otherwise these languages wouldn't have both of them. >From my personal experience, a typed list/seq solves most cases where I need the elements of an array to be strictly instances of a specific type. What I see typed list/seq like `string[]` has more ergonomics, it can be used to interact between libraries and application code without creating intermediate objects, while collection<Dict> proposal always requires declaring type - this simply multiplies the number of declared types and create more coupling where it is not needed! Also, most cases I work with are just fine with using just foreach or array_ family functions. I believe typed list/seq could also be used to implement custom collection like: class Article { function __construct(public string $title) {} } // collection(Seq) Articles<Article> { // } final class Articles { public function __construct(protected Article[] $articles = []) {} public function getIterator(): Traversable { return new ArrayIterator($this->articles); } } // or extend any other collection class with just typed list/seq property This doesn't have to collide with generics in any way, as mentioned before in the thread these features may exist simultaneously, typed list/seq can translate in the future to a generic type. I believe it'd make people's lives easier if we could have this in place soon. Don't you agree? Cheers, Michał Marcin Brzuchalski
