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Date: Mon, 23 Nov 2015 13:02:16 -0800
Cc: Phil Sturgeon <pjsturgeon@gmail.com>,
 PHP internals <internals@lists.php.net>
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To: Ryan Pallas <derokorian@gmail.com>
Subject: Re: [PHP-DEV] PHP7 Coalesce operator
From: shadda@gmail.com (shadda)

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That=E2=80=99s not a bad idea, but it=E2=80=99s still limited in certain =
cases, where your list of possibles is, lets say, complex.=20
At this point, I think you guys get what I=E2=80=99m after, and I=E2=80=99=
m wondering if anyone else finds the idea as useful I as do.

In fact, if it didn=E2=80=99t break the One Law of PHP (thou shalt not =
break BC), I might even suggest just giving ?: the same super power as =
??, in not throwing a notice.=20


> On Nov 23, 2015, at 12:52 PM, Ryan Pallas <derokorian@gmail.com> =
wrote:
>=20
> Well use null coalesce + elvis together then?
>=20
> // Coalesce possible null values, and use truthy comparison in elvis =
to "coalesce" to a default
> $var =3D ($_GET['possible_value'] ?? $_COOKIE['secondary'] ?? false) =
?: DEFAULTS['var'];
>=20
> On Mon, Nov 23, 2015 at 1:16 PM, shadda <shadda@gmail.com =
<mailto:shadda@gmail.com>> wrote:
> It=E2=80=99s not hate, I happen to like that ?? was added. I=E2=80=99m =
not raising a concern nor asking for a change in its behavior. Rather, =
I=E2=80=99m asking for another, similar operator that=E2=80=99s based on =
truth-evaluation (with PHP=E2=80=99s tender, loving conversion rules =
baked in), in *addition* to ?? which tests for null/undefined =
exclusively.
>=20
>=20
> > On Nov 23, 2015, at 12:08 PM, Phil Sturgeon <pjsturgeon@gmail.com =
<mailto:pjsturgeon@gmail.com>> wrote:
> >
> > On Mon, Nov 23, 2015 at 9:52 AM, shadda <shadda@gmail.com =
<mailto:shadda@gmail.com>> wrote:
> >> Er, that should read, =E2=80=9Canything non (null, false, =
undefined) is true=E2=80=9D
> >>
> >>> On Nov 23, 2015, at 11:51 AM, shadda <shadda@gmail.com =
<mailto:shadda@gmail.com>> wrote:
> >>>
> >>> Hey, thanks for responding.
> >>>
> >>> However, I still think that misses the point, or at least the true =
utility 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 indicator of truthiness.
> >>>
> >>> Basically in ECMA, anything non-null, false, or undefined is true. =
PHP is very similar in that regard, but our reliance on E_NOTICE to =
(ahem) enforce isset() checks is why, I assume, we=E2=80=99re =
introducing the ?? operator to begin with.
> >>>
> >>> I just think it=E2=80=99d be nice to have a small variation on =
this feature that was less concerned with a (defined|null) semantic and =
more in keeping with PHP=E2=80=99s overall handling of implicit type =
conversion in expressions.
> >>>
> >>> Does that make more sense?
> >>>
> >>>> On Nov 22, 2015, at 12:41 PM, Andrea Faulds <ajf@ajf.me =
<mailto: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=99=
s truthiness.
> >>>>
> >>>> 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/ <http://ajf.me/>
> >>>>
> >>>> --
> >>>> PHP Internals - PHP Runtime Development Mailing List
> >>>> To unsubscribe, visit: http://www.php.net/unsub.php =
<http://www.php.net/unsub.php>
> >>>>
> >>>
> >>
> >>
> >> --
> >> PHP Internals - PHP Runtime Development Mailing List
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<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. :)
>=20
>=20
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>=20
>=20


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