Making RCSlice and DIP74 work with const and immutable

[via Digitalmars-d]

On Sunday, 1 March 2015 at 15:08:47 UTC, H. S. Teoh wrote:
> On Sun, Mar 01, 2015 at 01:43:44PM +0000, via Digitalmars-d 
> wrote:
>> On Sunday, 1 March 2015 at 06:42:02 UTC, H. S. Teoh wrote:
> [...]
>> >So then Const!MyClass is a modified version of MyClass where 
>> >the data
>> >fields are const (similarly, we can define Immutable for the
>> >analogous purpose) but the fields marked as metadata will 
>> >remain
>> >mutable.
>> >
>> >Of course, this is just a crude first stab at the problem; 
>> >I'm sure
>> >there's plenty of room for refinement to make it more usable, 
>> >and to
>> >address some obvious roadblocks, like how to make MyClass 
>> >implicitly
>> >convertible to Const!MyClass, etc.. But it seems likely that 
>> >D's
>> >template machinery can actually express this in a way that 
>> >does not
>> >violate the guarantee of physical const.
>> 
>> You still cannot access it through a const reference, though.
>
> The whole point is to use Const!T instead of const(T).

But that's intrusive! You can only apply it code you control, or 
at least you have to convince everyone to use it.