Four draft:Third draft: Turn properties into first class accessors

[Richard (Rikki) Andrew Cattermole]

On 15/05/2025 3:29 AM, 12345swordy wrote:
> I had remove the array index section as I couldn't find anything that is 
> similar to what I am proposing in c# language. The one that I had found 
> is the array index to the class object itself and not as part of the 
> member variable/function itself, so that concept is definitely out of 
> the scope here.
> I had done a basic rewrite to better explain the code rewrite.
> 
> https://github.com/12345swordy/Public-Documents/commit/ 
> bf67cd7c77f953d752afc532dd43543b0d9be716
> 
> 
> 
> - Alex

I'm a little concerned about how the @property function arguments are 
working.

1. ``inout`` is legal on parameters ``void func(inout int);`` compiles. 
It utilizes the storage class to mean something other than "conditional 
const".

2. Following from 1, what if you wanted a parameter to just accept an 
int, I will note in your example it is by-value, not by-ref, where 
assignment is irrelevant.

3. Instead of splitting one parameter into two with the same name 
(breaks assumptions of one parameter per name, except for variadic), 
lower it to a struct which has two fields. This also solves for 
templates via use of ``alias this``.

4. You still need a way to request and handle the overload resolution 
for the property pair, I suggest using ``@property`` on the parameter to 
do so. However this may have ambiguity to the Type parameter, so another 
attribute may need to be used if it is offered.

i.e. a potential lowering:

```d
struct __PropertyPair(Getter, Setter) {
	Getter getter;
	Setter setter;

	alias getter this;

	void opAssign(T)(T value) {
		setter(value);
	}
}
```