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References: <CAMs36HdC6k0pjvjiXJDJhnUjSPeOnGSUFMn0FmyE2e0fZ1cCdQ@mail.gmail.com>
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In-Reply-To: <CAJmy8YF-63tQAujWYrjQCaH6V=ZcrdUzvdQ==bNB8MjARFuKjA@mail.gmail.com>
Date: Tue, 20 Dec 2022 09:15:07 +0100
Message-ID: <CAJmy8YHp6anOqwDOZ6x2AHEBeLdJNAG2gbtkv5Kkmiz125-P9A@mail.gmail.com>
To: Go Kudo <g-kudo@colopl.co.jp>
Cc: internals@lists.php.net, =?UTF-8?Q?Tim_D=C3=BCsterhus?= <tim@bastelstu.be>
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Subject: Re: [PHP-DEV] ext-random: add random_float() ?
From: divinity76@gmail.com (Hans Henrik Bergan)

btw while we're on the topic, does anyone know if this function gives
biased results/is-safe or not? i honestly don't know:
function random_float(float $min, float $max): float
{
    if ($min > $max) throw new \InvalidArgumentException("min must be
less than max");
    if ($min === $max) return $min;
    return $min + random_int(0, PHP_INT_MAX) / PHP_INT_MAX * ($max - $min);
}


On Tue, 20 Dec 2022 at 09:06, Hans Henrik Bergan <divinity76@gmail.com> wrote:
>
> >returns a value between 0.0 and 1.0.
>
> wouldn't it be better to follow random_int(int $min, int $max) design? eg
> random_float(float $min, float $max): float
>
> On Tue, 20 Dec 2022 at 07:27, Go Kudo <g-kudo@colopl.co.jp> wrote:
> >
> > Hi Internals.
> >
> > Congratulations on the release of PHP 8.2.
> > I just recently upgraded production PHP from 7.4 to 8.1 :)
> >
> > Now that my work is done, I was thinking about a proposal for a sunsetting
> > of existing functions for PHP 8.3 based on the features introduced in
> > ext-random, and I realized that there is no alternative to `lcg_value()`.
> >
> > Essentially, this could be completely replaced by
> > Random\Randomizer::getFloat(), but there are easier `random_int()` and
> > `random_bytes()` functions for ints and strings.
> >
> > The Randomizer may be overkill and complicated for PHP use cases where
> > random number reproducibility is not required in many cases.
> >
> > So, why not add a `random_float(): float` function? This function, like the
> > others, uses CSPRNG and returns a value between 0.0 and 1.0. This behavior
> > is `Closed` `Closed`.
> >
> > Opinions are welcome.
> >
> > Regards,
> > Go Kudo