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Subject: Re: [PHP-DEV] C# properties vs. accessors RFC
From: ralph@ralphschindler.com (Ralph Schindler)

Hi Steve,

> 2. C# has no issetter/unsetter.
>
> IMO customizing these functions is completely unneeded for the vast
> majority of use cases and could be replaced by simpler logic:
> isset($this->prop) calls the getter and compares to NULL;
> unset($this->prop) passes NULL to the setter.

I tend to agree here- I don't see a ton of value in isset/unset accessor 
functions.

> 3. C# has no auto-implementations.
>
> IMO auto implementations have some value removing boilerplate, but we
> should not make them violate #1. We could have the property syntax
> specify what field to use for underlying storage, or simply conclude
> that the boilerplate is worth the clarity.

Not completely true:
http://msdn.microsoft.com/en-us/library/bb384054.aspx

> I think the path forward is to determine how we can serve the same goals
> as this RFC, but retain the conceptual simplicity of the C#
> implementation and maybe syntax that strays less from current PHP.
>
> I have some ideas that I could start forging into an RFC. Consider this:
>
> class Foo {
>    private $_bar;
>    public function get bar { return $this->_bar; }
>    public function set bar { $this->_bar = $value; }
> }

This is too similar to what we have today:

class Foo {
    private $_bar;
    public function getBar() { return $this->_bar; }
    public function setBar($value) { $this->_bar = $value; }
}

> Advantages I see over the RFC:
> * It's clearer that the accessors map to regular methods, and you know
> how to control visibility of methods and how they're inherited.
> * It's clearer $bar doesn't exist as a property, and it will never show
> up in state inspection.
> * You know $_bar is a plain PHP property, and you can initialize it
> directly in the constructor; we don't need an "initter".
> * There are no guards/proxies/shadow property to think about

Personally, I don't see why 'default' can't be used:

class Foo {
    public $bar { get; set; default 5; }
}

This solves the var_dump() problem, and if people want dynamic get 
returning something other than the property/field value, so be it.

C# does indeed have an internal field per property though, even if it is 
an anonymous backing field.

-ralph