DIP23 draft: Fixing properties redux

[Steven Schveighoffer]

On Tue, 05 Feb 2013 13:33:35 -0500, Andrei Alexandrescu  
<SeeWebsiteForEmail at erdani.org> wrote:

> Walter and I reviewed the discussion and had a long talk. We are very  
> seriously considering banning the use of & against a ref result from a  
> function (and actually ref parameters and even struct members in @safe  
> code). One would still be able to take the address of a field in a class  
> because that's assumed to live on the GC heap.

What about structs that live on the heap?  e.g. a struct element of an  
array, or a struct member of a class instance.

I think the point about @safe code is moot, aren't pointers disallowed in  
safe code anyway?

> To get the address of an object in @system code without resorting to  
> operator& at all, we're considering adding a stdlib function implemented  
> like this (there are several other ways, this is just for illustration):
>
> @system T* addressOf(T)(ref T obj)
> {
>      static T* id(T* p) { return p; }
>      auto idr = cast(T* function(ref T)) id;
>      return idr(obj);
> }


I think a cast would be sufficient:

cast(int *)(&refparam); // understood that a cast is required

To jump through this machinery to turn a reference into a, um...  
reference, seems like a huge waste of code space and resources.

-Steve