Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:121658
MIME-Version: 1.0
References: <CAB-BujYUueXGAi+Mz1xjmy_AWGJy2VLzf6_rk3_O1tqaEbQ92w@mail.gmail.com>
In-Reply-To: <CAB-BujYUueXGAi+Mz1xjmy_AWGJy2VLzf6_rk3_O1tqaEbQ92w@mail.gmail.com>
Date: Sat, 11 Nov 2023 19:04:11 +0000
Message-ID: <CA+p1FaYk4_M+cczv8yRvefyfNhpPfcYMrQGc1x+S1Ai7-x_j=g@mail.gmail.com>
To: PHP internals <internals@lists.php.net>
Content-Type: multipart/alternative; boundary="000000000000d760a00609e51a8f"
Subject: Re: [PHP-DEV] Array functions with strict comparison
From: davidgebler@gmail.com (David Gebler)

--000000000000d760a00609e51a8f
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Sat, Nov 11, 2023 at 6:05=E2=80=AFPM Andreas Hennings <andreas@dqxtech.n=
et>
wrote:

> Hello internals,
> I noticed that array functions like array_diff(), array_intersect()
> etc use weak comparison.
>
>
That's not quite correct. Using the example of array_diff, the comparison
is a strict equality check on a string cast of the values. So
array_diff([""], [false]) will indeed be empty
but array_diff(["0"],[false]) will return ["0"].

Tbh any use case for whatever array function but with strict comparison is
such an easy thing to implement in userland[1] I'm not bothered about
supporting it in core. But that's just me. I don't generally like the idea
of adding new array_* or str_* functions to the global namespace without
very good cause. There is a precedent for it though, in terms of changes
which have gone through in PHP 8, such as array_is_list or str_starts_with.

[1] Example:

function array_diff_strict(array $array1, array ...$arrays): array
    {
        $diff =3D [];
        foreach ($array1 as $value) {
            $found =3D false;
            foreach ($arrays as $array) {
                if (in_array($value, $array, true)) {
                    $found =3D true;
                    break;
                }
            }
            if (!$found) {
                $diff[] =3D $value;
            }
        }
        return $diff;
    }

--000000000000d760a00609e51a8f--