DIP23 draft: Fixing properties redux

[Andrei Alexandrescu]

On 2/5/13 2:44 PM, Zach the Mystic wrote:
> On Tuesday, 5 February 2013 at 18:33:36 UTC, Andrei Alexandrescu wrote:
>> I have a DIP in the making that makes "ref" entirely sealed, i.e. it
>> makes it impossible to have a dangling ref in safe code. If that DIP
>> gets approved, then DIP23 gets considerably simplified because
>> operator& won't be applicable to the result of a function anymore.
>>
>>
>> Andrei
>
> I hope it at least considers my proposal with regard to 'out' return
> values. 'out' implies ref and guarantees that the result is as good as
> global:
>
> out int foo(ref int a) { return a; } // Error, 'out' return may not
> return ref parameter
> out int goo(ref int a) { return new int; } // Fine
>
> My impression was that this would solve 98% of problems, the other 2%
> requiring scope parameters, which also imply ref:
>
> ref int haa(ref int a, scope int b) { return b; } // Error, may not
> return scope parameter
> ref int gaa(ref int a, scope int b) { return a; } // Fine

I'm sorry, I didn't know of that proposal. Generally we're aiming for 
economy of means i.e. we want to clarify semantics of existing syntax 
instead of adding new syntax and semantics.

Andrei