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Date: Sat, 13 May 2023 11:36:59 +0100
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Subject: Re: [PHP-DEV] [RFC] [Discussion] nameof
From: rowan.collins@gmail.com (Rowan Tommins)

On 13 May 2023 10:04:39 BST, Lydia de Jongh <flexjoly@gmail=2Ecom> wrote:

>I prefer a magic constant like `::name` instead of a function call as it
>can be used in a wider scope; for example as a parameter in an Attribute=
=2E

Don't confuse the syntax with the implementation: "::class" isn't actually=
 a constant, and the proposed "nameof()" isn't actually a function; both ar=
e just syntaxes understood by the compiler to generate strings according to=
 certain rules=2E The RFC explicitly mentions use in attributes:

> The nameof() function is not necessarily a function in the traditional s=
ense and can be used anywhere a string literal can be used (such as to defi=
ne static constants, array keys, and attributes)=2E


I'm lukewarm on the RFC myself - I can't think of many places I'd use it, =
and some of the use cases feel like they would ideally not involve strings =
at all=2E But I can't actually think of a good reason *not* to include it=
=2E


The one part of the RFC that surprised me was this:

> When getting the name of constants and functions, the name will NOT be t=
he full name, but the lexical name=2E This means that if the name is use'd,=
 it will be that name=2E However, if the full name is used in the nameof(),=
 the full name is returned=2E

No reason is given *why* it works this way, and expanding the namespaces o=
n a name is one of the most useful features of "::class"=2E Importantly, it=
 means that the string created can be passed to other contexts, and still r=
efer to the same thing=2E For instance:

use function Acme\bar as foo;
=2E=2E=2E
#[SomeAttribute(callback: nameof(foo(=2E=2E=2E))]
=2E=2E=2E

The attribute constructor, defined in a different file, can't do anything =
useful with the string 'foo'; it needs to know the qualified name of the fu=
nction the user referenced, 'Acme\bar'=2E


Similarly, I'm not wholly clear why nameof(MyClass::method(=2E=2E=2E)) sho=
uld evaluate to "method" rather than "MyClass::method" or indeed "Full\Name=
spaceOf\MyClass::method"=2E Some more details on what exactly it evaluates =
to for each type, and why, would be helpful=2E

Regards,

--=20
Rowan Tommins
[IMSoP]