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 <CAG9XoMTc-7axJBQu2Skt6ng+6pU4o7gsXy+J47C5EeXyZLmZ=A@mail.gmail.com> <ecf37ece-51a9-5b41-5e68-cbcea3786e29@allenjb.me.uk>
In-Reply-To: <ecf37ece-51a9-5b41-5e68-cbcea3786e29@allenjb.me.uk>
Date: Fri, 5 Feb 2021 13:52:29 +0100
Message-ID: <CAG9XoMTsgrQetKA9jkZC9-pxq7aYSgS3FEWLPMmTjSE_vS70GA@mail.gmail.com>
To: AllenJB <allen@allenjb.me.uk>
Cc: "G. P. B." <george.banyard@gmail.com>, PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Warning for implicit float to int conversions
From: benjamin.morel@gmail.com (Benjamin Morel)

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On Fri, 5 Feb 2021 at 11:56, AllenJB <allen@allenjb.me.uk> wrote:

> (And after checking the manual, I'd also note here that round() also
> returns a float, so how exactly does your example here work? Is it only
> OK to explictly cast a float that's the return value of a function? Or
> only explictly cast a float if the fractional part is .0? Is that viable
> given the "inaccuracy" of floats? Or would it be better for PHP to have
> some non-range/accuracy-sensitive representation for integers (and
> decimals) here?) (and now we're getting into "why are we still using
> floating point math by default in 2021" territory, so I'll stop right her=
e)
>

Floats (doubles) can accurately represent all integers up to 2=E2=81=B5=C2=
=B3, so there
is no inaccuracy in this range; the result from round() or floor() could
therefore be safely passed to (int) even if the cast operator checked for a
0 fractional part, which is what I'm advocating for.

There are legitimate cases for explicitly casting floats to int. For
> example floor() outputs a float, but in the context of the domain I'm
> working I might know that the result is never going to exceed a certain
> value and want the result explicitly as an int.


Perfect, so (int) floor() would work wonders for you, even with the strict
casting I'm talking about.
And if the result does overflow an integer one day, I'm sure you'd be happy
to know it by getting an exception, rather than getting silently ZERO:

echo (int) 1e60; // 0

=E2=80=94 Benjamin

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