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Date: Fri, 14 Sep 2012 12:08:12 +0400
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To: Ralph Schindler <ralph@ralphschindler.com>
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Subject: Re: [PHP-DEV] [VOTE] ::class feature to resolve namespaced class
 names to scalars
From: dmitry@zend.com (Dmitry Stogov)

Hi Ralph,

You persuade me. :)

The SOMETHING::class syntax looked wired to me because I didn't 
understand it.

However, the SOMETHING::class syntax might be considered as a reference 
to a predefined class constant and in this case it looks quite 
consistent. I suggest to reflect it in RFC and documentation (if we 
agree to include it in release) to avoid future misunderstanding.

Also I would expect SOMETHING::class to work in all cases where class 
constants work. e.g. self::class, parent::class, static::class, 
$obj::class. To do it for parent, static and $obj you'll probably need a 
new opcode - ZEND_FETCH_CLASSNAME that must be very similar to 
ZEND_FETCH_CLASS. May be it's possible to do the same using 
ZEND_FETCH_CONSTANT, but I don't think it makes sense to complicate the 
existing opcode.

SOMETHING::class must be consistent with traits.

In case all the above works, I say +1 and even may help with implementation.

Finally, may be SOMETHING::__CLASS__ is a bit more clear than 
SOMETHING::class.

Thanks. Dmitry.



On 09/14/2012 12:51 AM, Ralph Schindler wrote:
>
>> I think the syntax is wired.
>> Instead of classname::class I would prefer something like
>> class(classname).
>>
>
> I am not a big fan of the syntax class(ShortClass\Name) as to me it
> looks like a function call.
>
> Personally, I like drawing parallels from the same languages that I
> think helped shaped PHP's object-model.  In this case, the Java has a
> similar enough feature where Type.class returns a class object (in our
> case we just need to return a string of the FQ class name).
>
> Your suggestion is similar to that of, I think, C# where
> typeof(SomeClassName) would return a reflection-like/type object where
> you could get the FullName():
>
> http://msdn.microsoft.com/en-us/library/58918ffs%28v=vs.71%29.aspx
>
> I could go either way, at this point (after the April discussion on the
> matter), I had not really given much thought to class() lang. construct.
>
> Personally, ::class feels a bit better to me in that the context feels
> more "compile-time", like __CLASS__, and the NS resolutions, than does
> class() that you suggest.
>
>  From a wider perspective, I've seen these variations in the wild:
>
> class Foo {
>    const CLASSNAME = __CLASS__;
>    // or
>    const _class = __CLASS__;
> }
>
> Which allows for the usage:
>
>    Foo::CLASSNAME;
>
> for example.
>
> FWIW, both reusing the class() keyword making it BC, which is something
> I like.
>
> -ralph
>
>