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Date: Wed, 16 Oct 2019 14:41:02 +0700
Message-ID: <CAP=w73X4sBBFtn=Z1OKfo0cdSZbd1-fst+5MFs5+8m2pEMxQew@mail.gmail.com>
To: =?UTF-8?Q?Micha=C5=82_Brzuchalski?= <michal.brzuchalski@gmail.com>
Cc: PHP Internals List <internals@lists.php.net>
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Subject: Re: [PHP-DEV] Inline switch as alternative to nested inline conditional
From: webdevxp.com@gmail.com (Kosit Supanyo)

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Hi Michal

I'had the idea similar to your RFC but instead of using `switch` keyword I
think introducing `when` keyword is better. (as I know a language that uses
this keyword is Kotlin)

$result =3D when ($v) {
    'foo' =3D> 1,
    'bar' =3D> 2,
    'x', 'y', 'z' =3D> 3,
    default =3D> null,
};

Above you can see that `when` syntax is more semantic than `switch`. And it
is easier to implement in parser because it has no statement/expression
ambiguity.

But this might not be preferred by BC camps because introducing a new
keyword might break BC.
And if `switch` is chosen I still think the syntax should be comma
separated instead of semicolon separated for consistency with other list
expressions (array/function call).

$result =3D switch ($v) {
    case 'foo' =3D> 1,
    case 'bar' =3D> 2,
    case 'x', 'y', 'x' =3D> 3,
    default =3D> null,
};

Cheers


On Wed, Oct 16, 2019 at 10:33 AM Micha=C5=82 Brzuchalski <
michal.brzuchalski@gmail.com> wrote:

> Hi David,
>
> I'm interested in this feature this is called switch expression and is on
> my list of RFC to process after Object Initializer RFC.
>
> I have an RFC in draft for that and planning to finish it soon together
> with some syntax optimisations - you can see it at
> https://wiki.php.net/rfc/switch-expression-and-statement-improvement
>
> Cheers,
> Micha=C5=82 Brzuchalski
>
> =C5=9Br., 16 pa=C5=BA 2019, 03:46 u=C5=BCytkownik David Rodrigues <david.=
proweb@gmail.com
> >
> napisa=C5=82:
>
> > Hello. I like to suggests a discussion about a FR to make possible to
> > inline switch, as an alternative to nested inline conditionals.
> >
> > $value =3D switch (expr()) {
> >     case A1: return A2;
> >     case B1: return B2;
> >     default: return C;
> > }
> >
> > Instead of:
> >
> > $expr =3D expr();
> > $value =3D $expr =3D=3D A1 ? A2 : ( $expr =3D=3D B1 ? B2 : C );
> >
> > Just a discussion to check what do you think.
> >
> > --
> > David Rodrigues
> >
>

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