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Date: Fri, 10 Jan 2020 15:26:15 +0100
Message-ID: <CAC5V6gj=tkqxf5n3EtayP5WkA0827rDfd=JKBnLxy60L4aALYA@mail.gmail.com>
To: Kalle Sommer Nielsen <kalle@php.net>
Cc: Mike Schinkel <mike@newclarity.net>, Ralph Schindler <ralph@ralphschindler.com>, 
	Internals <internals@lists.php.net>
Content-Type: text/plain; charset="UTF-8"
Subject: Re: [PHP-DEV] [RFC] Allow ::class on objects
From: guilliam.xavier@gmail.com (Guilliam Xavier)

Hi,

On Thu, Jan 9, 2020 at 10:02 PM Kalle Sommer Nielsen <kalle@php.net> wrote:
>
> [...]
>
> use Interfaces;
> if(!$object instanceof Interfaces\MyInterface)
> {
> // Notice the ! is right associative and instanceof is non
> associative, hence the lack of parantheses
> }

Sorry for off-topic but that comment is incorrect: the fact that
`!$x instanceof Foo` is evaluated as
`!($x instanceof Foo)` (which I find more readable with explicit
parentheses, by the way) is not due to the *associativity* of the
operators but to their relative *precedence*.
For instance, `===` is non-associative too but
`!$x === 42` is evaluated as
`(!$x) === 42` (not as `!($x === 42)`).

According to the docs, associativity only matters for operators of
equal precedence, e.g.
`4 - 3 - 2` is evaluated as
`(4 - 3) - 2`,
and
`4 ** 3 ** 2` is evaluated as
`4 ** (3 ** 2)`.

-- 
Guilliam Xavier