Re: [RFC] Transform void into an alias for null

From:	Tim Düsterhus	Date:	Wed, 04 Jun 2025 08:50:56 +0000
Subject:	Re: [RFC] Transform void into an alias for null
References:	1 2 3 4	Groups:	php.internals
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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