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Date: Thu, 6 Feb 2025 13:42:26 +0500
Message-ID: <CAJWOiuNQ+ue-ZyY3EfnEQGo9JJ5mjf=tByxp31M__N71_ODy6A@mail.gmail.com>
Subject: [PHP-DEV] RFC: Not Null Assertion Operator
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From: 91liahim@gmail.com (Mihail Liahimov)

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Thank you for your answer. Now I will give examples for better
understanding.

Simple examples from Typescript:

let foo = ...
foo!.bar()
foo!.someProperty.baz()

Examples of potentially using in PHP:
Without this operator we writing this code:

$foo = ...

if ($foo === null) {
    throw new FooIsNullException();
}

$foo->bar.

With this operator:

$foo!->bar
$foo!->someProperty->method();
$foo!->someProperty->anotherProperty!->method();

I think the postfix operator would be illogical in PHP because my operator
is similar to the existing nullsafe operator in syntax. And it would be
strange if its syntax were different.
Or we can implement both operator syntaxes: prefix for accessing
properties, and postfix for use with variables, as in your example.

Nullsafe:
$foo?->bar;
Not null assertion:
$foo!->bar;

If variable bar would be null - php will throw an exception. But now i dont
know which exception it would be :)

This operator will be useful in cases where a null value in a specific
place will violate the domain logic. Usually we write either assertions or
checks and throw our exceptions for this. But it seems to me that the not
null assertion operator will help avoid writing unnecessary code. The
problem, of course, will be catching errors. It is not clear how to catch
errors by a specific value. I will think about it.

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<div dir=3D"ltr">Thank you for your answer. Now I will give examples for be=
tter understanding.<br><br>Simple examples from Typescript:<br><br>let foo =
=3D ...<br>foo!.bar()<br>foo!.someProperty.baz()<br><br>Examples of potenti=
ally using in PHP:<br>Without this operator we writing this code:<br><br>$f=
oo =3D ...<br><br>if ($foo =3D=3D=3D null) {<br>=C2=A0 =C2=A0 throw new Foo=
IsNullException();<br>}<br><br>$foo-&gt;bar.<br><br>With this operator:<br>=
<br>$foo!-&gt;bar<br>$foo!-&gt;someProperty-&gt;method();<br>$foo!-&gt;some=
Property-&gt;anotherProperty!-&gt;method();<br><br>I think the postfix oper=
ator would be illogical in PHP because my operator is similar to the existi=
ng nullsafe operator in syntax. And it would be strange if its syntax were =
different.<br>Or we can implement both operator syntaxes: prefix for access=
ing properties, and postfix for use with variables, as in your example.<br>=
<br>Nullsafe:<br>$foo?-&gt;bar;<br>Not null assertion:<br>$foo!-&gt;bar;<br=
><br>If variable bar would be null - php will throw an exception. But now i=
 dont know which exception it would be :)<br><br>This operator will be usef=
ul in cases where a null value in a specific place will violate the domain =
logic. Usually we write either assertions or checks and throw our exception=
s for this. But it seems to me that the not null assertion operator will he=
lp avoid writing unnecessary code. The problem, of course, will be catching=
 errors. It is not clear how to catch errors by a specific value. I will th=
ink about it.<br></div>

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