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Date: Wed, 31 Aug 2022 23:26:58 +0200
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To: Larry Garfield <larry@garfieldtech.com>,
 php internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Asymmetric visibility
From: tim@bastelstu.be (=?UTF-8?Q?Tim_D=c3=bcsterhus?=)

Hi

On 8/31/22 22:43, Larry Garfield wrote:
> ## References make everything worse
> 
> […]
> 
> That problem wouldn't happen if all we're changing is visibility, however.  That means in the C# style, we would need to differentiate whether the block on the right is intended to disable references or not.  Ilija has proposed `raw` to indicate that.  That would mean:
> 
> ```php
> class Test
> {
>     public $a { private set; }
>     public $b { private raw; }
> 
>     public function inScope()
>     {
>         echo $this->a; // echo $this->getA();
>         $this->a = 'a'; // $this->setA('a');
>        
>         echo $this->b; // echo $this->b;
>         $this->b = 'b'; // $this->b = 'b';
>     }
> }
> 
> $test = new Test();
> 
> echo $test->a; // echo $test->getA();
> $test->a = 'a'; // Error, set operation not accessible
> 
> echo $test->b; // echo $test->getB();
> $test->b = 'b'; // Error, set operation not accessible
> ```
> 
> The take-away for the asymmetric visibility only case is that we would need to use `raw` instead of `set`, in order to avoid confusion later with accessor hooks and whether or not to disable references.
> 
> The Swift-style syntax, as it does not require any hook-like syntax to just control visibility, does not have this problem.  There is no ambiguity to resolve, so no need for a `raw` keyword.
> 

I've read through that explanation three times, but don't understand why 
the C#-style syntax would require to differentiate between `set` and 
`raw`. Isn't the difference between "visibility only" and "accessor" not 
clear [1] by having either '{' or ';' after the 'set'?

[1] Read: Clear to the engine, not talking about the human reader here.

Best regards
Tim Düsterhus