Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:99476
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: error (pb1.pair.com: domain kelunik.com from 81.169.146.218 cause and error)
MIME-Version: 1.0
In-Reply-To: <D5EC4A68-A8E1-4F2A-9022-B5B1BD0BF7E6@koalephant.com>
References: <CAFMT4Npoo_ZrRk-kk4C6KHYEtV93pU7Wmh0FhaPi6Z-9qkObaQ@mail.gmail.com>
 <CADqTB_hWrhBBQetfp=-LFR=OYALHwhs=mYd3vPQOYGGng26UsA@mail.gmail.com>
 <4077c099-2247-c3c1-7dee-02a6b25f8586@fleshgrinder.com> <CAObuZdtHXp=icU_aB8dWyjbzW-yZ0sSTW6ObmEsxTuvR679-Fw@mail.gmail.com>
 <CAObuZdvck_w5iEeH5Sz23pDS1T727gtN7pn8XCiPWBvqVWR5Ag@mail.gmail.com>
 <CAObuZdvYX8Yr4KQnzJNeF8CSJVwpxuDevV+6=w_J5J9gx5R8HQ@mail.gmail.com>
 <559b73f7-c40f-e593-f0e1-51b56210d7cb@telia.com> <2053A608-6B66-42FB-A6D7-7CC64E94DA6A@koalephant.com>
 <4FBDE643-1EBC-485A-A39F-7E28C5D4807A@koalephant.com> <e1c608a0-d046-d3a8-a360-d33c3aa75666@telia.com>
 <034f3ebf-95b8-a7cf-1279-77c7cf0424d7@gmail.com> <46143e7c-ef75-7c05-eaa9-98c8f3b405f1@telia.com>
 <CAESVnVrLG4nRrcm7MYAQutb4umLq=FkGo2CWHYqHw+bYo72Bsg@mail.gmail.com>
 <d45a3327-59d4-5c93-1425-70cc2d08a87e@telia.com> <CAESVnVpQtLXhKnUn2EE4s7rZn11r5Kpj2zOSOKRCWFaxaeOrjg@mail.gmail.com>
 <CANUQDCg_x8VHbjsm9BjXeC5vOPuasRe7cWWZP3zszRzFiR3HaQ@mail.gmail.com>
 <04c92b98-0fb2-6288-f22e-ebcc45cfecac@telia.com> <D5EC4A68-A8E1-4F2A-9022-B5B1BD0BF7E6@koalephant.com>
Date: Sat, 10 Jun 2017 14:43:49 +0200
Message-ID: <CANUQDCigJ1ahxX9ZQEuqwpf6WoXi1B6XBYb9HkO=k8gaMeskrw@mail.gmail.com>
To: Stephen Reay <php-lists@koalephant.com>
Cc: =?UTF-8?Q?Bj=C3=B6rn_Larsson?= <bjorn.x.larsson@telia.com>, 
	Sara Golemon <pollita@php.net>, Rowan Collins <rowan.collins@gmail.com>, 
	PHP internals <internals@lists.php.net>
Content-Type: multipart/alternative; boundary="001a113db9e4098b2505519a70e7"
Subject: Re: [PHP-DEV] [RFC]Discuss] Syntax for Arrow Functions
From: me@kelunik.com (Niklas Keller)

--001a113db9e4098b2505519a70e7
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

2017-06-10 11:09 GMT+02:00 Stephen Reay <php-lists@koalephant.com>:

>
> > On 10 Jun 2017, at 15:19, Bj=C3=B6rn Larsson <bjorn.x.larsson@telia.com=
>
> wrote:
> >
> > Den 2017-06-09 kl. 22:00, skrev Niklas Keller:
> >> 2017-06-09 15:44 GMT+02:00 Sara Golemon <pollita@php.net>:
> >>
> >>> On Fri, Jun 9, 2017 at 7:23 AM, Bj=C3=B6rn Larsson <
> bjorn.x.larsson@telia.com>
> >>> wrote:
> >>>> If I take the liberty in using the example above on our option list:
> >>>> 1. $someDict->map(fn($v) =3D> $v * 2)->filter(fn($v) =3D> $v % 3);
> >>>> 2. $someDict->map(function($v) =3D> $v * 2)->filter(function($v) =3D=
> $v %
> >>> 3);
> >>>> 3. $someDict->map($v =3D=3D> $v * 2)->filter($v =3D=3D> $v % 3);
> >>>> 4. $someDict->map(($v) =3D> $v * 2)->filter(($v) =3D> $v % 3);      =
  //
> >>>> Ambiguous
> >>>> 5. $someDict->map([]($v) =3D> $v * 2)->filter([]($v) =3D> $v % 3);
> >>>>
> >>>> Old proposals:
> >>>> 6. $someDict->map($v ~> $v * 2)->filter($v ~> $v % 3);
> >>>> 7. $someDict->map(lambda($v) =3D> $v * 2)->filter(lambda($v) =3D> $v=
 % 3);
> >>>>
> >>> Something else which really pops in these examples is the effect of
> >>> not needing to use parentheses when embedding a single-arg short
> >>> lambda.   3 and 6 in your list read cleaner to me (due to the lack of
> >>> parenthesis clutter).  Sadly ~> has the same hacky implementation
> >>> issues as =3D=3D>, but I think that shows a little bit of why the Hac=
kLang
> >>> team decided the messy lexer was worth the clearer syntax.
> >>
> >> Another possible syntax (dunno whether this has already been suggested
> >> on-list):
> >>
> >> $function =3D { $x =3D> 2 * $x };
> >> $function =3D { ($x) =3D> 2 * $x };
> >> $function =3D | $x =3D> 2 * $x |;
> >> $function =3D | ($x) =3D> 2 * $x |;
> >>
> >> Nikita and Levi prefer it with parenthesis, I prefer it without,
> because I
> >> think it's unnecessary clutter.
> >>
> >> A reason to use | ... | instead of { ... } would be to allow future
> object
> >> literals.
> >>
> > Applying that to Sara's example becomes:
> > 8. $someDict->map({$v =3D> $v * 2})->filter({$v =3D> $v % 3});
> > 9. $someDict->map(|$v =3D> $v * 2|)->filter(|$v =3D> $v % 3|);
> >
> > I also find that parenthesis makes it cluttered.
> > $someDict->map({($v) =3D> $v * 2})->filter({($v) =3D> $v % 3});
> >
> > Cheers //Bj=C3=B6rn
> >
> >
> > --
> > PHP Internals - PHP Runtime Development Mailing List
> > To unsubscribe, visit: http://www.php.net/unsub.php
>
> I find it quite odd that people are claiming paren=E2=80=99s around 0 arg=
uments is
> =E2=80=98clutter=E2=80=99, but curly braces or pipes around the entire th=
ing is somehow not
> clutter. While I understand there are small differences like implicit
> return and automatic capturing, having such wildly different syntax to a
> regular still doesn=E2=80=99t make much sense to me.


The difference is that `{ ... }` or `| ... |` is required to be
unambiguous, otherwise it conflicts with other parser rules.

Regards, Niklas

--001a113db9e4098b2505519a70e7--