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Date: Fri, 23 Oct 2020 16:14:49 -0400
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To: Rowan Tommins <rowan.collins@gmail.com>,
 Andreas Bittner <php@philiagus.de>
Subject: Re: [PHP-DEV] Is there any interest for object constructor shorthand
 *just forstdClass*
From: mike@newclarity.net (Mike Schinkel)

> On Oct 23, 2020, at 2:33 PM, Rowan Tommins <rowan.collins@gmail.com> =
wrote:
>=20
> I don't follow; is the resulting JSON different if you cast to object, =
or is there some other reason you prefer an object over using an =
associative array directly?

The by-reference semantics of objects vs arrays in PHP.

> Also, to clarify my earlier comment about stdClass not being necessary =
now we have anonymous classes, I meant it very directly: every time you =
write "new stdClass" you can write "new class {}" instead.
>=20
> The fact that "(object)$foo" creates an instance of "stdClass" rather =
than an instance of "class{}" is just a historical wart, which can be =
easily replaced:
>=20
> function array_to_object($arr): object {
>     $obj =3D new class {};
>     foreach ( $arr as $key =3D> $value ) {
>         $obj->{$key} =3D $value;
>     }
>     return $obj;
> }

That pattern can have a non-insignificant performance penalty when =
dealing with a large number of objects, a use-case that is not =
infrequent when processing JSON, especially responses returned via an =
HTTP API.


> On Oct 23, 2020, at 11:08 AM, Andreas Bittner <php@philiagus.de> =
wrote:
>=20
> Wouldn't it be opportune to just use named arguments?
>=20
> $x =3D new \stdClass(
>    prop: new \stdClass(
>        a: $a,
>        b: $b
>    )
> );

You illustrate of useful pattern here.=20

What would be nicer, however, would be an object instantiation shorthand =
that would omit the "new" by using braces:

$x =3D \stdClass{
   prop: \stdClass{
       a: $a,
       b: $b,
   },
}

Also:

$x =3D \Foo{
   prop: \Bar{
       a: $a,
       b: $b,
   },
}

And for instantiating anonymous classes:

$x =3D {
   prop: {
       a: $a,
       b: $b,
   },
}


-Mike