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Date: Fri, 07 Feb 2025 15:23:48 +0100
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Subject: [PHP-DEV] Short class syntax and inner classes
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From: rob@bottled.codes ("Rob Landers")

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Hey internals,

You may remember my RFC about Records (https://wiki.php.net/rfc/records)=
. There was something intentionally left out, and due to life events, I =
am quite behind schedule on this one. BUT, what I left out (and the main=
 reason for the short syntax) is the ability to have locally scoped reco=
rds in a class definition.

Example using an anonymous record:

$x =3D new class {
  public record Point(int $x, int $y);

  // from inside the class, there is no special scope
  public function foo(): Point {
    return new Point(1, 1);
  }
}

$point =3D new $x::Point(1, 2);

Anyway, I think I've settled on an implementation that is acceptable, bu=
t I wanted your feedback before moving forward.

Instead of this being limited to Records -- an entirely new type of type=
 and syntax -- would we rather have short class declarations (similar to=
 the rules in the Records RFC) and locally scoped classes?

class Outer {
  // able to be instantiated from anywhere
  public class Inner(int $y);
  // a private/protected class can only be instantiated within methods/c=
lasses bound to Outer
  protected readonly class ProtectedInner(int $z);
}

Instantiation is done by static access: new Outer::Inner(1), which is cu=
rrently a syntax error. Public nested classes may be used as type hints =
and return types as well as properties in other classes.

There are quite a few more things left to investigate before updating th=
e RFC (or drafting a new one), but I am at a crossroads and I wanted to =
gather people's feedback first. If this is a big "NO" (or if someone els=
e has started working on this and I'm just so happening to accidentally =
step on their toes, again): I don't want to spend several days/weeks dig=
ging into the details for classes. However, it would probably look somet=
hing like the above.

Note, this doesn't preclude you from using a longer syntax, if that is y=
our preference.

class Outer {
  public class Inner {
    public function __construct(public int $z) {}
  }
}

Anyway, I'd love to hear any preferences or thoughts -- strong or otherw=
ise. I probably won't reply, but I will read everything and take it into=
 consideration as I continue down this road.

Also, if there is already someone working on this ... please speak up so=
 I don't get accused of stealing ideas again!

=E2=80=94 Rob
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<!DOCTYPE html><html><head><title></title><style type=3D"text/css">p.Mso=
Normal,p.MsoNoSpacing{margin:0}</style></head><body><div>Hey internals,<=
br></div><div><br></div><div>You may remember my RFC about Records (<a h=
ref=3D"https://wiki.php.net/rfc/records">https://wiki.php.net/rfc/record=
s</a>). There was something intentionally left out, and due to life even=
ts, I am quite behind schedule on this one. BUT, what I left out (and th=
e main reason for the short syntax) is the ability to have locally scope=
d records in a class definition.<br></div><div><br></div><div>Example us=
ing an anonymous record:</div><div><br></div><div>$x =3D new class {<br>=
</div><div>&nbsp; public record Point(int $x, int $y);<br></div><div><br=
></div><div>&nbsp; // from inside the class, there is no special scope</=
div><div>&nbsp; public function foo(): Point {<br></div><div>&nbsp; &nbs=
p; return new Point(1, 1);<br></div><div>&nbsp; }</div><div>}<br></div><=
div><br></div><div>$point =3D new $x::Point(1, 2);</div><div><br></div><=
div>Anyway, I think I've settled on an implementation that is acceptable=
, but I wanted your feedback before moving forward.<br></div><div><br></=
div><div>Instead of this being limited to Records -- an entirely new typ=
e of type and syntax -- would we rather have short class declarations (s=
imilar to the rules in the Records RFC) and locally scoped classes?<br><=
/div><div><br></div><div>class Outer {<br></div><div>&nbsp;&nbsp;// able=
 to be instantiated from anywhere<br></div><div>&nbsp; public class Inne=
r(int $y);<br></div><div>&nbsp;&nbsp;// a private/protected class can on=
ly be instantiated within methods/classes bound to Outer<br></div><div>&=
nbsp; protected readonly class ProtectedInner(int $z);<br></div><div>}<b=
r></div><div><br></div><div>Instantiation is done by static access: new =
Outer::Inner(1), which is currently a syntax error. Public nested classe=
s may be used as type hints and return types as well as properties in ot=
her classes.<br></div><div><br></div><div>There are quite a few more thi=
ngs left to investigate before updating the RFC (or drafting a new one),=
 but I am at a crossroads and I wanted to gather people's feedback first=
. If this is a big "NO" (or if someone else has started working on this =
and I'm just so happening to accidentally step on their toes, again): I =
don't want to spend several days/weeks digging into the details for clas=
ses. However, it would probably look something like the above.<br></div>=
<div><div><br></div><div>Note, this doesn't preclude you from using a lo=
nger syntax, if that is your preference.<br></div><div><br></div><div>cl=
ass Outer {<br></div><div>&nbsp; public class Inner {<br></div><div>&nbs=
p; &nbsp; public function __construct(public int $z) {}</div></div><div>=
&nbsp; }<br></div><div>}<br></div><div><br></div><div>Anyway, I'd love t=
o hear any preferences or thoughts -- strong or otherwise. I probably wo=
n't reply, but I will read everything and take it into consideration as =
I continue down this road.<br></div><div><br></div><div>Also, if there i=
s already someone working on this ... please speak up so I don't get acc=
used of stealing ideas again!</div><div><br></div><div id=3D"sig12122915=
2">=E2=80=94 Rob</div></body></html>
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