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Date: Wed, 04 Jun 2025 10:50:56 +0200
To: "Gina P. Banyard" <internals@gpb.moe>
Cc: Ilija Tovilo <tovilo.ilija@gmail.com>, PHP internals
 <internals@lists.php.net>
Subject: Re: [PHP-DEV] [RFC] Transform void into an alias for null
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From: tim@bastelstu.be (=?UTF-8?Q?Tim_D=C3=BCsterhus?=)

Hi

Am 2025-06-03 17:46, schrieb Gina P. Banyard:
>> > IMO, these checks are useful enough not to be removed.
>> 
>> I agree with Ilija (and also Rowan).
> 
> Well, I'm not sure Ilija and Rowan agree between each other.

I believe they agree in that the distinction between `void` and `null` 
is a useful one.

> AFAIU Ilija thinks void living on its weird island is good.
> Meanwhile, Rowan thinks it is somewhat confusing and that void should 
> be a subtype of null.

But indeed I'm more aligned with Ilija than Rowan (that’s why Rowan’s 
name is in parentheses).

>> To me there is an important semantic difference between “not returning 
>> anything”
>> and “always returning null”.
>> I believe that `void` being in a distinct type
>> hierarchy is the right choice and when considering “untyped returns” 
>> to
>> be soft-deprecated / discouraged, there are no inconsistencies either.
> 
> Then our type system is not logical as we have a top type that is not 
> actually a top type.

See my reply to your reply to Ilija.

Best regards
Tim Düsterhus