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In-Reply-To: <CE981907-0CDD-421F-BC01-1B3F0E95B199@newclarity.net>
Date: Wed, 12 Feb 2020 08:12:53 +0100
Message-ID: <CAC5V6gjS7QqZubVjufmHNOdkSeGCULCgT=pOc5oFB5Se-Pcu0Q@mail.gmail.com>
To: Mike Schinkel <mike@newclarity.net>
Cc: Chase Peeler <chasepeeler@gmail.com>, PHP Internals List <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC]
From: guilliam.xavier@gmail.com (Guilliam Xavier)

On Wed, Feb 12, 2020 at 4:58 AM Mike Schinkel <mike@newclarity.net> wrote:
>
> Or best would be to add ::nameof for functions, method, classes, interfac=
es and traits

One problem is how would `x::nameof` resolve when you have several `x`
symbols (of distinct kinds) in scope?

```
namespace Theirs {

class Foo {}
const BAR =3D 2;
function qux() { return '3'; }

}

namespace Mine {

use Theirs\Foo as x;
use const Theirs\BAR as x;
use function Theirs\qux as x;

var_dump(new x); // object(Theirs\Foo)#1
var_dump(x); // int(2)
var_dump(x()); // string(1) "3"

// *** hypothetical: ***

assert(x::class =3D=3D=3D 'Theirs\Foo');
assert(x::const =3D=3D=3D 'Theirs\BAR');
assert(x::function =3D=3D=3D 'Theirs\qux');

assert(x::nameof =3D=3D=3D ???);

}
```

> Returning a _closure_ instead of a string would be providing a feature we=
 _already_ have instead of one we do _not_ have.
>
> If we had ::function returning a string we could use Closure::fromCallabl=
e() to get a closure.  Or today just use fn() =3D> myfunc().
>
> But if ::function instead returned a closure then there still would be no=
 way to extract the name of a function as a string from a symbol where PHP =
can throw a warning if it does not recognize the symbol, such as in the cas=
e of a typo.
>
> Seems to me having a shorter syntax to get a closure is an orthogonal con=
cern.
>
> If we want a shorthand for closure we should create an additional syntax =
for it but still provide a way to extract a function's name as a string fro=
m its symbol since that is currently _not_ possible. Getting a closure from=
 a function symbol currently _is_ possible.
>
> Much better to provide  ::function to return the name of the function and=
 ::closure get a closure that can call the function.
>
> Or have  ::function to return the name of the function and provide a synt=
ax something like ${myfunc} to return a closure, which has been suggested l=
ater in this thread.

That might deserve consideration indeed...

--=20
Guilliam Xavier