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Date: Mon, 23 Nov 2015 10:08:10 -1000
Message-ID: <CABDNdAHzThRpg8NowzBef8zLVFEQtVGA8xpGEUajvHnhZ6Wtxw@mail.gmail.com>
To: shadda <shadda@gmail.com>
Cc: PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] PHP7 Coalesce operator
From: pjsturgeon@gmail.com (Phil Sturgeon)

On Mon, Nov 23, 2015 at 9:52 AM, shadda <shadda@gmail.com> wrote:
> Er, that should read, =E2=80=9Canything non (null, false, undefined) is t=
rue=E2=80=9D
>
>> On Nov 23, 2015, at 11:51 AM, shadda <shadda@gmail.com> wrote:
>>
>> Hey, thanks for responding.
>>
>> However, I still think that misses the point, or at least the true utili=
ty of what I=E2=80=99m proposing.
>>
>> In practice, you can ignore E_NOTICE and php will happily treat null and=
 !isset() as the same thing in *most* cases, so that=E2=80=99s not a good i=
ndicator of truthiness.
>>
>> Basically in ECMA, anything non-null, false, or undefined is true. PHP i=
s very similar in that regard, but our reliance on E_NOTICE to (ahem) enfor=
ce isset() checks is why, I assume, we=E2=80=99re introducing the ?? operat=
or to begin with.
>>
>> I just think it=E2=80=99d be nice to have a small variation on this feat=
ure that was less concerned with a (defined|null) semantic and more in keep=
ing with PHP=E2=80=99s overall handling of implicit type conversion in expr=
essions.
>>
>> Does that make more sense?
>>
>>> On Nov 22, 2015, at 12:41 PM, Andrea Faulds <ajf@ajf.me> wrote:
>>>
>>> Hi,
>>>
>>> shadda wrote:
>>>> I had a question-suggestion based around the cool new operator we=E2=
=80=99re getting in PHP7, the ?? operator, which as I understand it is the =
functional equivalent to perl=E2=80=99s // operator; in that they both test=
 for whether or not a variable is defined, rather than it=E2=80=99s truthin=
ess.
>>>
>>> This is not strictly correct. Though something of a misnomer, the 'null=
 coalesce operator' checks if a variable doesn't exist, but also that it is=
 not null, i.e. it functions like isset().
>>>
>>> Thanks.
>>>
>>> --
>>> Andrea Faulds
>>> http://ajf.me/
>>>
>>> --
>>> PHP Internals - PHP Runtime Development Mailing List
>>> To unsubscribe, visit: http://www.php.net/unsub.php
>>>
>>
>
>
> --
> PHP Internals - PHP Runtime Development Mailing List
> To unsubscribe, visit: http://www.php.net/unsub.php
>

Ignoring E_NOTICE is generally considered bad practice by many, and
turning them off just to use ternaries instead of null coalesce (a
feature we already have) doesn't seem like a benefit.

The ?? is used the same as "a =3D b || c" in Ruby or JS. Doing that in
PHP wouldn't work well as || works a bit differently, so ?? is used
instead, just like C and Swift.

Basically... it's all good. And even if you hate it you're months too
late to raise a concern. :)