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Date: Wed, 02 Oct 2024 13:29:38 -0500
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Subject: Re: [PHP-DEV] [RFC] [Discussion] Add get_declared_enums() function
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From: larry@garfieldtech.com ("Larry Garfield")

On Wed, Oct 2, 2024, at 7:27 AM, Alexandru P=C4=83tr=C4=83nescu wrote:

> I think my view comes from when I initially dug (15+ years ago) into=20
> what an enum in Java is, and learned that it is just a syntactic sugar=
,=20
> and a final class would be generated implementing `Comparable` and=20
> extending an abstract class `Enum`.
>=20
> And I think in PHP that could be a similar view. And most of the=20
> limitations we have are not impossible to create with a standard class.

That is roughly the way enums are implemented in several languages, incl=
uding PHP. =20

> I think in time we might get to remove some limitations.
> I, personally, don't agree with the `Stringable` related limitation.

This has been discussed numerous times already. Please don't bring it up=
 here, it's not relevant to this thread.

> And also with the limitation on no state. In Java this is the simple=20
> way to create a singleton: an enum with one case; and we can't have=20
> this in PHP.

That is what we mean by ADTs or Tagged Unions (various names for the sam=
e thing), and it's something Ilija and I have on the roadmap.  It's been=
 on the roadmap since the first enum release, but we deliberately punted=
 it for later to keep the initial RFC manageable.  It's also dependent o=
n the pattern matching RFC, which hopefully we'll be able to bring up fo=
r discussion for 8.5.

> If we remove the limitations, should we reclassify at that point enums=20
> as classes?

Enums already are classes.  I don't know what reclassification you're ta=
lking about.  The RFC is about adding a "get me a list of only those cla=
sses that are enums" function to PHP.  Changing how Enums behave or are =
implemented is wildly out of scope.

--Larry Garfield