Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:109813
To: Ilija Tovilo <tovilo.ilija@gmail.com>, PHP internals
	<internals@lists.php.net>
Thread-Topic: [PHP-DEV] Re: [DISCUSSION] Match expression
Thread-Index: AQHWF0BYxxJ9i22Q4E++xgAoT9Xhl6iGmlMAgAAaq4CAAA0PqQ==
Date: Thu, 23 Apr 2020 14:16:38 +0000
Message-ID:
 <DM6PR07MB6618AB93367613CD2C050B20F9D30@DM6PR07MB6618.namprd07.prod.outlook.com>
References:
 <CAPyj-LDfdATXFD+dc5AY9EqWWxgf8LP1joD2fzvm==1gUoN35A@mail.gmail.com>
 <CAPyj-LAM7yS0U0TZY9pLyuysuz3KikHjegZ6ESYPLTNfT02yPQ@mail.gmail.com>
 <CA+kxMuSOMuPpkJScf1TeqCvCeD0An8LCsMa=ONL2FQ+s+J1cpg@mail.gmail.com>,<CAPyj-LB3upRqoLAO76Y9jUzs+0qcXv4zfj-fbeZC_bY2Mycikg@mail.gmail.com>
In-Reply-To:
 <CAPyj-LB3upRqoLAO76Y9jUzs+0qcXv4zfj-fbeZC_bY2Mycikg@mail.gmail.com>
Accept-Language: en-CA, en-US
Content-Language: en-CA
x-ms-exchange-messagesentrepresentingtype: 1
x-tmn: [6LGFCuLfJjMzwR8nh98OJy+BqWLdXj69]
x-ms-publictraffictype: Email
x-incomingheadercount: 45
x-eopattributedmessage: 0
x-ms-office365-filtering-correlation-id: efd97691-59ce-4038-e2fc-08d7e790f002
x-ms-traffictypediagnostic: CO1NAM11HT201:
x-microsoft-antispam: BCL:0;
x-microsoft-antispam-message-info:
 Jjf8JmsJjj1exeTQldEv2cHEJ+A+2szk0oKRyyMfDDHCuzVIZG942UWq+AU9Ehc0XfRKHTNlLFcN7FRd8w3i7zytW2A+aYlexYkl27MLmgN6thA3qWQWrv+SCtcC5euvVTk4jKSl7mKJCfn9UOIXOBuGtvVm3QgPgPHansHakidcbmo6QoHKq0UCYgtqAlPnbl5xvDK1FXTk9rzEp8wlL3SbWW7Bpbg22Ah1965xDdM3KT4NoDZADFuIl8lx/wdM
x-forefront-antispam-report:
 CIP:255.255.255.255;CTRY:;LANG:en;SCL:0;SRV:;IPV:NLI;SFV:NSPM;H:DM6PR07MB6618.namprd07.prod.outlook.com;PTR:;CAT:NONE;SFTY:;SFS:;DIR:OUT;SFP:1901;
x-ms-exchange-antispam-messagedata:
 dcYtQ71Nu/LXr6spIl7+TAehWh/pw4CUWIqC6CVVtw5VJQgA4XV3tKvBJtxNHsQsgGar3k+bbZGmymiV05ntfYWKDMQkhKxidtwOp38XYJKG6aU0qDU7S+GjjWAGMgQBg5KiC1SIlgccSExJoq8c0w==
x-ms-exchange-transport-forked: True
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
MIME-Version: 1.0
X-OriginatorOrg: hotmail.com
X-MS-Exchange-CrossTenant-RMS-PersistedConsumerOrg: 00000000-0000-0000-0000-000000000000
X-MS-Exchange-CrossTenant-Network-Message-Id: efd97691-59ce-4038-e2fc-08d7e790f002
X-MS-Exchange-CrossTenant-rms-persistedconsumerorg: 00000000-0000-0000-0000-000000000000
X-MS-Exchange-CrossTenant-originalarrivaltime: 23 Apr 2020 14:16:38.3992
 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Internet
X-MS-Exchange-CrossTenant-id: 84df9e7f-e9f6-40af-b435-aaaaaaaaaaaa
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO1NAM11HT201
Subject: Re: [PHP-DEV] Re: [DISCUSSION] Match expression
From: tysonandre775@hotmail.com (tyson andre)

Hi Ilija,=0A=
=0A=
>=A0This is because we don't generate a jumptable when there are less than=
=0A=
> 5 integer conditions. Because of this inconsistency I'm not sure if we=0A=
> should just remove the warning. As you mentioned, it could be=0A=
> intentional in some cases. Tyson also mentioned that some constants=0A=
> are platform dependent which would make it warn on some platforms but=0A=
> not on others.=0A=
=0A=
It's also inconsistent in that the float, false, null, true, and possibly a=
rrays not containing objects or references don't have warnings.=0A=
=0A=
I'd prefer to go with leaving that check for linters or static analyzers, r=
ather than an E_COMPILE_WARNING, because php compiles at runtime (unless pr=
eload is used properly)=0A=
Multiple static analyzers can do this for switch, e.g. `phan --plugin Dupli=
cateArrayKeyPlugin` =0A=
https://github.com/phan/phan/tree/master/.phan/plugins#duplicatearraykeyplu=
ginphp=0A=
=0A=
If we did start doing this, I'd personally want it both for switch and matc=
h at the same time to be consistent, as a separate RFC.=0A=
=0A=
Another idea I'd thought of would be to add an `opcache.pedantic` mode for =
checks like that,=0A=
which would warn about errors noticed by opcache (emitted at compile time, =
not runtime) within a single file without running the code=0A=
(e.g. calling a function with the wrong type (strlen($obj), too few or too =
many arguments to native functions, dead code (e.g. conditions that were al=
ways true/false on a platform), etc).=0A=
=0A=
- Due to platform dependence, that would have false positives, which is why=
 this would be called pedantic=0A=
- This would emit errors directly to a log file or stderr, in order to not =
trigger side effects such as user error handlers=0A=
=0A=
- Tyson=