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Date: Fri, 5 Apr 2024 12:24:30 +0200
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Subject: Re: [PHP-DEV] RFC idea: using the void type to control maximum arity
 of user-defined functions
To: Ilija Tovilo <tovilo.ilija@gmail.com>,
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From: tim@bastelstu.be (=?UTF-8?Q?Tim_D=C3=BCsterhus?=)

Hi

On 4/4/24 23:27, Ilija Tovilo wrote:
>> I think it would be reasonable to consider deprecating passing extra
>> arguments to a non-variadic function.
> 
> IIRC one of the bigger downsides of this change are closure calls that
> may provide arguments that the callee does not care about.
> 
> […]
> 
> The user may currently choose to omit the $key parameter of the
> closure, as it is never used. In the future, this would throw. We may
> decide to create an exemption for such calls, but I'm not sure
> replacing one inconsistency with another is a good choice.

I must admit, I find the

> This RFC considers that anonymous functions are not intended to have a formal signature and should skip the exceeding argument count check.

bit of the previous RFC pretty reasonable to reduce the impact of the 
deprecation: I expect this type of callback to primarily be implemented 
as a single-use closure, which aren't really part of a package's API and 
thus relaxed checks are fine for those.

I also don't primarily see deprecating passing of superfluous parameters 
as removing an inconsistency. The more important bit for me is the 
improved error checking, i.e. I'd prefer to resolve the inconsistency in 
favor of the stricter checks, instead of relaxing the checks for 
internal functions. The previous RFC showcases multiple examples where 
it found bugs that likely were introduced during refactoring.

Best regards
Tim Düsterhus