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Date: Thu, 4 Feb 2021 18:06:24 +0000
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To: PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Warning for implicit float to int conversions
From: davidgebler@gmail.com (David Gebler)

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If this were to be done, my gut feeling is a notice would be preferable to
a warning, particularly as there must be many scripts which would suddenly
start churning out warnings for this proposed change which might/probably
ignore lower error levels and emitting a warning for a previously common
script behaviour is quite a significant backwards incompatible change.

The bit which makes me more nervous about the proposed change is your
rationale that implicit float to int conversion dropping the fractional
portion means there is "no way to know if the data provided is erroneous".

I get the idea behind your proposal, but equally I'm not convinced this is
comparable to numeric vs non-numeric or malformed/partially numeric
strings. There isn't any value of the string "foobar" which makes sense as
an integer. But there is a value for a float which makes sense as an
integer; the integral part. In the float 3.81232 the integral portion 3 is
completely unambiguous. It's not like it would make just as much sense to
interpret it as any other arbitrary integer value.

So in these cases, via coercion you're just straightforwardly giving a
valid, unambiguous integer to something which expects an integer. I'd
question why should that raise a warning or TypeError.

In favour of the proposal are a couple of the other issues you mentioned
which mean this would make PHP a bit more consistent all-round...but I'm
not entirely persuaded at this point.

-Dave

On Thu, Feb 4, 2021 at 4:05 PM G. P. B. <george.banyard@gmail.com> wrote:

> Greetings internal,
>
> I'm proposing a new RFC which would warn when an implicit conversion
> from float to int occurs.
>
> The draft is currently located on GitHub:
> https://github.com/Girgias/float-int-warning/
> for ease of commenting/providing changes to it.
>
> The official discussion phase wouldn't start before I convert it to docwiki
> and
> post it on the wiki, something I'm planning to do next week.
>
> Any feedback is appreciated.
>
> Best regards,
>
> George P. Banyard
>

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