On Wed, Oct 18, 2023 at 3:47 PM Deleu <deleu...@gmail.com> wrote:
>
> On Wed, Oct 18, 2023 at 4:14 AM Olle Härstedt <olleharst...@gmail.com>
> wrote:
>
> > 2023-10-17 21:39 GMT+02:00, Rowan Tommins <rowan.coll...@gmail.com>:
> > > On 16/10/2023 15:08, Olle Härstedt wrote:
> > >> Hello internals,
> > >>
> > >> Was there a previous discussion about the pros/cons of adding only the
> > >> syntax needed for generics, but not the functionality? So static
> > >> analyzers could use it, instead of docblocks. I looked at externals.io
> > >> but couldn't find anything specific.
> > >
> > >
> > > Hi Olle,
> > >
> > > Since I haven't seen it expressed quite this way in the previous
> > > discussion, I'd like to highlight what I think is a major downside to
> > > this approach, at least as commonly proposed:
> > >
> > > Using the same syntax for type information that is guaranteed to be true
> > > (existing run-time checks) and type information that is "advisory only"
> > > (new checks for optional static analysis) means users can no longer have
> > > confidence in that type information.
> > >
> > > This is one of the interesting things about the compromise over scalar
> > > types - if you see a declaration "function foo(int $bar) { ... }", you
> > > *know* that $bar will be an int at the start of every invocation of that
> > > function, regardless of which mode the calling code uses. I think adding
> > > exceptions to that certainty would be a bad direction for the language.
> > >
> > > On the other hand, I can see a "third way": if the problem with current
> > > static analysis conventions is that they have to be parsed out of a
> > > string-based docblock, we can provide *dedicated* syntax, without
> > > unifying it with the standard type syntax. For instance, some of the
> > > earlier discussions around introducing attributes suggested reflection
> > > expose the AST of the attributes arguments, rather than the resolved
> > > expressions, allowing them to act a bit like Rust's "hygienic macros".
> > > If that was added as an optional mode, you might be able to do something
> > > like this:
> > >
> > > #[RawAttribute]
> > > class GenericType {
> > > public function __construct(AST\Node $typeInfo) { ... }
> > > }
> > >
> > > function foo(#[GenericType(int|float)] array $foo) {
> > > // array is the type guaranteed by the language
> > > // static analysis libraries can get the GenericType attribute from
> > > reflection and receive an AST representing the type constraint int|float
> > > }
> >
> > Not sure readability is improved here compared to existing @template
> > annotations. ;)
> >
> > Olle
> >
>
> I won't be participating much about this discussion because I lack
> expertise to add too much. I just wanted to voice a small (and defeated)
> minority of PHP developers that don't want/care for Generics. I've been
> working with Typescript lately and I see generics only being useful for
> library code and even then when I end up writing some valid Generics stuff,
> Typescript verbosity becomes so bloated that it invalidates the added-value
> of the functionality.
>
> I truly can't understand how Generics is the most requested PHP feature so
> I will just assume I will have to live with it one day, but mixing it with
> Attributes Syntax seems to be a recipe to make it as bad (or worse) than
> the experience of using Generics in Typescript.
>
>
> --
> Marco Deleu
I also agree with Marco. Generics are a pain in the rear in languages
that have them. Usually, the PHP version of the same code written in
generic C# or Typescript is much more concise and clear. The only
exception to that, would be built-in arrays. If there is exactly one
thing that could be "generic", it would be those that. Effectively, a
simpler syntax to this:
function onlyStrings(string ...$strings): array { return $strings; }
onlyStrings(...['array','of','strings']);
I'd be thrilled if I could just write:
function onlyStrings(array<string> $strings): array<string> { return $strings; }
onlyStrings(['array','of','strings']);
That is all I want whenever I think of Generics in PHP. The rest is
just complicated fluff in my humble opinion.
Robert Landers
Software Engineer
Utrecht NL
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