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Date: Wed, 13 Aug 2014 14:45:52 +0200
Message-ID: <CAH-PCH4+QZUVtjASAN7he=CMLoJxVmt1YEufuqbsZ7GZktr27g@mail.gmail.com>
To: Rowan Collins <rowan.collins@gmail.com>
Cc: PHP Internals <internals@lists.php.net>
Content-Type: multipart/alternative; boundary=001a113987201585f20500822b90
Subject: Re: [PHP-DEV] [RFC] Disallow multiple default blocks in a single
 switch statement
From: tyra3l@gmail.com (Ferenc Kovacs)

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On Wed, Aug 13, 2014 at 2:42 PM, Ferenc Kovacs <tyra3l@gmail.com> wrote:

>
>
>
> On Wed, Aug 13, 2014 at 2:27 PM, Rowan Collins <rowan.collins@gmail.com>
> wrote:
>
>> Ferenc Kovacs wrote (on 13/08/2014):
>>
>>> agree, and I thought about mentioning that, but I left that out, becaus=
e
>>> I'm not proposing to remove that ability (and I see more use-cases for =
that
>>> as mentioned in my previous email) but stating that this patch would ma=
ke
>>> an arbitrary distinction between the normal and the default cases.
>>>
>>
>> I'm not sure I agree that it's arbitrary. Having a switch with two
>> "default" clauses is like having an if with two "else" clauses; specifyi=
ng
>> two case labels which can be true at the same time is like having two
>> "elseif" clauses chained together that can both be true at the same time=
.
>> One is clearly an error; the other is just poorly written logic, and you
>> can't make the parser outlaw every instance of poor logic.
>
>
>
> Default is more of a catch all directive than an else (which will only
> match if nothing else), so I don't think that having two default is more
> "wrong" than having two "case 2:".
>
> --
> Ferenc Kov=C3=A1cs
> @Tyr43l - http://tyrael.hu
>

Btw. I've added a comment to https://bugs.php.net/bug.php?id=3D67757 as I'v=
e
found some really weird behavior for multiple defaults and I think that it
would be better to try to figure out and fix why do we pick the last
default in the problematic snippet instead of trying to remove the multiple
default support to get rid of the setup which can make this bug to surface.

--=20
Ferenc Kov=C3=A1cs
@Tyr43l - http://tyrael.hu

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