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Date: Sun, 17 May 2026 21:42:27 +0300
Message-ID: <CAPyeZ4OmbkRXnjPvKeGJMrAC1cZiSKfq+t21wx81veQjqjdZ0w@mail.gmail.com>
Subject: Re: [PHP-DEV] Coalescing and nullsafe same time
To: Vadim Dvorovenko <vadim.dvorovenko@gmail.com>
Cc: PHP internals list <internals@lists.php.net>
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From: udaltsov.valentin@gmail.com (Valentin Udaltsov)

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Vadim Dvorovenko <vadim.dvorovenko@gmail.com>:

> Sorry for raising such an ancient topic.
>
> =D0=90ccidentally noticed, that construction like
> `$arr['undefined']?->foo()->bar` causes error, and not behaves the same,
> as `($arr['undefined'] ?? null)?->foo()->bar`.
>
> Readed docs, https://wiki.php.net/rfc/nullsafe_operator, asked google
> and learned, that there were much discussions about such behavior, and
> it was chosen deliberately. Nevertheless, structures like
> `(($arr['undefined'] ?? null)?->foo()->bar)` does not looks pretty for
> me. `$arr['undefined']->foo->bar ?? null` works great, until function
> calls appears in chain, and `$arr['undefined']->foo()->bar ?? null`
> breaks. It looks like objects are our favorites for short and safe
> operations, but arrays are not.
>
> But during development, you can equally easily encounter typed arrays
> (for example, with a structure described through phpdocs), and working
> directly with properties, and traditional getters. An structured
> associative array that has optional fields is also a common pattern. And
> in large projects these patterns they can be found in almost any
> combination.
>
> So it looks like the language needs a construct for pretty code in such
> cases. What do you think it should look like?
>
> * Make nullsafe operator to be coalescing too. Making
> `$arr['undefined']?->foo()->bar` no to cause error, but return null
>
> * Some new coalescing-nullsafe-operator, `??->`.
> `$arr['undefined']??->foo()->bar` suppressing all errors to the left
> same way `??` does.
>
> * Some new nullsafe-array-access operator `$arr?-['key']`. This leads to
> `$arr?-['key']->foo()->bar` for cases where we are sure that array has
> key. Supposed short-circuiting working here too.
>
> * Some new coalesce-array-access operators `$arr??-['key']`. Making
> `$arr??-['key']->foo()->bar` for cases, there we are not sure, that
> array has key.
>
> * Suppress function call on nulls and undefined errors in
> `$var->foo()->bar() ?? null`.
>

Hi, Vadim!

I've seen discussions about that and also considered proposing something
similar, so thank you for bringing that up!

I see two questions here:

1. Accessing an array offset on a nullable value ($arrayOrNull['offset'])
2. Treating a non-existent array offset as null ($objects[0]?->prop)

For the first case, the syntax could be symmetric to ?->:

? + -> =3D ?->
? + [$offset] =3D ?[$offset]

$arrayOrNull?['offset'] , equivalent to $arrayOrNull =3D=3D=3D null ? null =
:
$arrayOrNull['offset']

For the second case:

$objects[?0]?->prop , equivalent to ($objects[0] ?? null)?->prop

--
Valentin

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<div dir=3D"ltr"><div dir=3D"ltr">Vadim Dvorovenko &lt;<a href=3D"mailto:va=
dim.dvorovenko@gmail.com">vadim.dvorovenko@gmail.com</a>&gt;:</div><div cla=
ss=3D"gmail_quote gmail_quote_container"><blockquote class=3D"gmail_quote" =
style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);pa=
dding-left:1ex">Sorry for raising such an ancient topic.<br>
<br>
=D0=90ccidentally noticed, that construction like <br>
`$arr[&#39;undefined&#39;]?-&gt;foo()-&gt;bar` causes error, and not behave=
s the same, <br>
as `($arr[&#39;undefined&#39;] ?? null)?-&gt;foo()-&gt;bar`.<br>
<br>
Readed docs, <a href=3D"https://wiki.php.net/rfc/nullsafe_operator" rel=3D"=
noreferrer" target=3D"_blank">https://wiki.php.net/rfc/nullsafe_operator</a=
>, asked google <br>
and learned, that there were much discussions about such behavior, and <br>
it was chosen deliberately. Nevertheless, structures like <br>
`(($arr[&#39;undefined&#39;] ?? null)?-&gt;foo()-&gt;bar)` does not looks p=
retty for <br>
me. `$arr[&#39;undefined&#39;]-&gt;foo-&gt;bar ?? null` works great, until =
function <br>
calls appears in chain, and `$arr[&#39;undefined&#39;]-&gt;foo()-&gt;bar ??=
 null` <br>
breaks. It looks like objects are our favorites for short and safe <br>
operations, but arrays are not.<br>
<br>
But during development, you can equally easily encounter typed arrays <br>
(for example, with a structure described through phpdocs), and working <br>
directly with properties, and traditional getters. An structured <br>
associative array that has optional fields is also a common pattern. And <b=
r>
in large projects these patterns they can be found in almost any <br>
combination.<br>
<br>
So it looks like the language needs a construct for pretty code in such <br=
>
cases. What do you think it should look like?<br>
<br>
* Make nullsafe operator to be coalescing too. Making <br>
`$arr[&#39;undefined&#39;]?-&gt;foo()-&gt;bar` no to cause error, but retur=
n null<br>
<br>
* Some new coalescing-nullsafe-operator, `??-&gt;`. <br>
`$arr[&#39;undefined&#39;]??-&gt;foo()-&gt;bar` suppressing all errors to t=
he left <br>
same way `??` does.<br>
<br>
* Some new nullsafe-array-access operator `$arr?-[&#39;key&#39;]`. This lea=
ds to <br>
`$arr?-[&#39;key&#39;]-&gt;foo()-&gt;bar` for cases where we are sure that =
array has <br>
key. Supposed short-circuiting working here too.<br>
<br>
* Some new coalesce-array-access operators `$arr??-[&#39;key&#39;]`. Making=
 <br>
`$arr??-[&#39;key&#39;]-&gt;foo()-&gt;bar` for cases, there we are not sure=
, that <br>
array has key.<br>
<br>
* Suppress function call=C2=A0on nulls and undefined=C2=A0errors in <br>
`$var-&gt;foo()-&gt;bar() ?? null`.<br>
</blockquote></div><div><br>Hi, Vadim!<br><br>I&#39;ve seen discussions abo=
ut that and also considered proposing something similar, so thank you for b=
ringing that up!<br><br>I see two questions here:<br><br>1. Accessing an ar=
ray offset on a nullable value ($arrayOrNull[&#39;offset&#39;])<br>2. Treat=
ing a non-existent array offset as null ($objects[0]?-&gt;prop)<br><br>For =
the first case, the syntax could be symmetric to ?-&gt;:<br><br>? + -&gt; =
=3D ?-&gt;<br>? + [$offset] =3D ?[$offset]<br><br>$arrayOrNull?[&#39;offset=
&#39;] , equivalent to $arrayOrNull =3D=3D=3D null ? null : $arrayOrNull[&#=
39;offset&#39;]<br><br>For the second case:<br><br>$objects[?0]?-&gt;prop ,=
 equivalent to ($objects[0] ?? null)?-&gt;prop<br><br>--<br>Valentin</div><=
/div>

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