Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:116293
Date: Fri, 22 Oct 2021 14:41:27 +0100
To: "Claude Pache" <claude.pache@gmail.com>
Cc: "internals" <internals@lists.php.net>
Message-ID: <17ca83c277d.dc53327f1579308.2336162242535956459@pmmp.io>
In-Reply-To: <D8DA00D4-1EC3-4FFF-A2FE-872FDA9DDB6E@gmail.com>
References: <17c9ff9e9da.10b3e7f1c1280030.5141627710284677362@pmmp.io> <D8DA00D4-1EC3-4FFF-A2FE-872FDA9DDB6E@gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Importance: Medium
User-Agent: Zoho Mail
Subject: Re: [PHP-DEV] Add ReflectionFunctionAbstract::isAnonymous()
From: dktapps@pmmp.io ("Dylan K. Taylor")


---- On Fri, 22 Oct 2021 14:19:23 +0100 Claude Pache <claude.pache@gmail.co=
m> wrote ----

 >=20
 > Le 21 oct. 2021 =C3=A0 01:12, Dylan K. Taylor <dktapps@pmmp.io> a =C3=A9=
crit :
 >=20
 > Hi all,=20
 >=20
 > Given the addition of Closure::fromCallable() and the upcoming first-cla=
ss callable syntax in 8.1, it seems slightly problematic that there's no si=
mple way to tell by reflection if a Closure refers to an anonymous function=
 or not. ReflectionFunctionAbstract::isClosure() (perhaps somewhat misleadi=
ngly) returns whether the closure is literally a \Closure instance, so it's=
 not useful for this purpose.=20
 >=20
 > The only way to do this currently (that I know about) is to check if the=
 name of the function contains "{closure}", which is a bit unpleasant and d=
epends on undocumented behaviour.=20
 >=20
 > I'm proposing the addition of ReflectionFunctionAbstract::isAnonymous(),=
 which would fill this use case, and may be able to offer an implementation=
.=20
 >=20
 > Thanks,=20
 > Dylan Taylor.=20
 >=20
 >=20
 > --=20
 > PHP Internals - PHP Runtime Development Mailing List
 > To unsubscribe, visit: https://www.php.net/unsub.php
 >=20
 >=20
 >=20
 > Hi,
 >=20
 > Per the manual [1], Closure::fromCallable() =E2=80=9Ccreates and returns=
 a new anonymous function=E2=80=9D. I guess that this might not match your =
notion of =E2=80=9Canonymous function=E2=80=9D?
 >=20
 > Therefore, I am asking for clarification: What practical distinction do =
you make between =E2=80=9Dan instance of Closure=E2=80=9D and =E2=80=9Can a=
nonymous function=E2=80=9D, and why does this distinction matter?
 >=20
 > [1]: https://www.php.net/manual/en/closure.fromcallable.php
 >=20
 > =E2=80=94Claude
 >=20

Hi Claude,=20
Sorry for the double email, my previous reply got bounced from the mailing =
list because I replied from the wrong address.

An anonymous function would be an unnamed function, e.g. arrow function or =
function(){}.

I guess the documentation for Closure::fromCallable() ought to be updated, =
because Closure::fromCallable('namedFunc') isn't really anonymous, it's a \=
Closure object that refers to a named function. A \Closure may refer to a n=
amed or an anonymous function, and currently there's no way to tell the dif=
ference without hacks.

The distinction is important for reflection cases, such as the one Aaron me=
ntioned, and also like generating a pretty name for closures in a project I=
 maintain [1].

It's a fringe use case for sure, but considering we already have Reflection=
Class->isAnonymous(), I think it makes sense.

[1]: https://github.com/pmmp/PocketMine-MP/blob/986b4e0651d665c72ec011542f9=
5b4bd9529c6a8/src/pocketmine/utils/Utils.php#L144

Dylan